Soil Erosion, Its Impacts and Conservation

<div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiKwr0KFKyJsAzuz53TrUVjvQURUq79vCoT4sZcpHGDi9XoKR53SjsSuHvRCp8v4dKPSDyrX07DwZMBntQCx4OVM0rgnkBkaT7z34hdPCPFUlGGwrLt0PUFcgma73w-4a3pHD2ZXL9YRRkO/s1600/img.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="456" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiKwr0KFKyJsAzuz53TrUVjvQURUq79vCoT4sZcpHGDi9XoKR53SjsSuHvRCp8v4dKPSDyrX07DwZMBntQCx4OVM0rgnkBkaT7z34hdPCPFUlGGwrLt0PUFcgma73w-4a3pHD2ZXL9YRRkO/s640/img.jpg" width="640" /></a></div> <div class="MsoNormal"> <span style="font-size: 14pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <span style="font-size: 14pt; line-height: 115%;">Soil erosion refers to as <b>the movement of soil particle form one place to another place. It is a natural process</b>. It occurs at relatively slow rate and its magnitude is unnoticed. Wind and water are the major two agents of natural soil erosion. Due to the anthropogenic activities, quality of the soil is degraded. Thereby soil makes more vulnerable to soil erosion. Continuous removal of topsoil from agricultural lands affects the crop yield and environment quality.</span></div> <div class="MsoNormal"> <span style="font-size: 14pt; line-height: 115%;"><br /></span></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-family: symbol; font-size: 14pt; line-height: 115%;">·<span style="font-family: "times new roman"; font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">        </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Driven factors of soil erosion</span></b><span style="font-size: 14pt; line-height: 115%;">:<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Deforestation</span></b><span style="font-size: 14pt; line-height: 115%;">: Cut down and remove of vegetation from land left bare soil.  It makes the soil more vulnerable to both wind and water erosion. Removal of vegetation directly affects the organic matter content in the soil. Due to the low organic matter availability, soil particles are not aggregated together. Fine soil particles of topsoil are more easily wash away or blown from the surface. Due to the absence of vegetation wind has the opportunity to directly contact the soil surface.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Overgrazing</span></b><span style="font-size: 14pt; line-height: 115%;">: Unregulated grazing of livestock reduces the thickness of the grass layer of pasture lands so it makes more vulnerable to erosion. Livestock press topsoil into the subsoil. It reduces the infiltration capacity of the soil. So it increases the runoff. Thereby it increases the amount of soil to move through the water.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Tillage</span></b><span style="font-size: 14pt; line-height: 115%;">: Although tillage brings lots of advantages for agriculture, improper tillage practices cause negative consequences. Tillage buries topsoil and brings subsoil into the upper surface. It increases the surface area of soil exposed to wind and rain. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">4)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14pt; line-height: 115%;">Construction of roads and other infrastructure: Soils has to be removed in large scale in road and railways constructions. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpLast" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">5)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Mining</span></b><span style="font-size: 14pt; line-height: 115%;">: gem mining and coal mining processes dig and remove a large portion of topsoil and subsoil from the land. <o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: 0.25in;"> <b><span style="font-size: 14pt; line-height: 115%;">Water erosion</span></b><span style="font-size: 14pt; line-height: 115%;">: runoff is able to dislodge the fine soil particles from the soil surface. It causes onsite effects and offsite effects. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Gully erosion: </span></b><span style="font-size: 14pt; line-height: 115%;">As a result of the high flow of velocity, the deep channel is formed by the removal of soil and soft rocks. Riverbank is subjected to gully erosion due to the high velocity of river flow. After heavy rain, gully erosion also can be observed at the bottom of the sloppy area.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Sheet erosion</span></b><span style="font-size: 14pt; line-height: 115%;">: It is the removal of the soil particles from the surface by a thin layer of water. It removes soil more uniformly over the surface. As it happens at a slow rate, it cannot be easily observed until a significant amount of topsoil is lost. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Rill erosion</span></b><span style="font-size: 14pt; line-height: 115%;">: It forms well defined small channels over the surface as a result of strong surface runoff. It can be observed in steep land and lands with gradual sloping. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in;"> <br /></div> <div class="MsoListParagraphCxSpLast" style="margin-left: 0.75in;"> <b><span style="font-size: 14pt; line-height: 115%;">Wind erosion</span></b><span style="font-size: 14pt; line-height: 115%;">: It is abraded, transports, and deposes of soil by the action of wind. <o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: 0.25in;"> <br /></div> <div class="MsoNormal" style="margin-left: 0.25in;"> <b><span style="font-size: 14pt; line-height: 115%;">Onsite effects of erosion</span></b><span style="font-size: 14pt; line-height: 115%;">: <o:p></o:p></span></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Reduce crop yields</span></b><span style="font-size: 14pt; line-height: 115%;">: topsoil is the most fertile layer of soil that directly affects plant growth. It contains organic matter, nutrients, and microorganisms in large quantities. It is continuously replenished by litterfall, organic matter decomposition, nutrients cycling, and mineral weathering. After the loss of topsoil, subsoil falls to fulfill all nutrient requirements of the plant which results in a reduction of crop yelled. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in;"> <br /></div> <div class="MsoListParagraphCxSpLast" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Reduce land stability</span></b><span style="font-size: 14pt; line-height: 115%;">: Continuous removal of soil makes the land prepare for the landslides.it causes loss of people, ecosystem and properties. <o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: 0.25in;"> <b><span style="font-size: 14pt; line-height: 115%;">Offsite effects: <o:p></o:p></span></b></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Siltation of aquatic bodies</span></b><span style="font-size: 14pt; line-height: 115%;">: Soils particles that are washed away from the land tend to deposit at the bottom of the lakes or streams. It reduces the water holding capacity of the aquatic body which increases the flood risk of the area. Soils deposit in the bottom vegetation. So it interferes with the breeding places and habitats.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Eutrophication:</span></b><span style="font-size: 14pt; line-height: 115%;"> Excess nutrients including phosphates and nitrates bound soil particles to accelerate the growth of algae in the aquatic ecosystem. The sudden increase of algal growth refers to as the algal bloom. Some algal species produce toxic substances that are toxic to animal and plant life.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Aquatic pollution:</span></b><span style="font-size: 14pt; line-height: 115%;"> The soil acts as itself pollution. Dissolved soil increases the turbidity which results in a reduction of light penetration through the aquatic bodies. Thereby the productivity of deep layers of aquatic bodies is reduced. In addition to nutrients, pesticides also attach to soil particles toxic to aquatic animals. They tend to accumulate through the food web and cause detrimental effects on the animals at the top levels. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-family: symbol; font-size: 14pt; line-height: 115%;">·<span style="font-family: "times new roman"; font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">        </span></span><!--[endif]--><span style="font-size: 14pt; line-height: 115%;">Following actions are suggested to minimize the erosion by wind or water.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Mulching</span></b><span style="font-size: 14pt; line-height: 115%;">: organic mulches including fiber woods and straw, plastic and rubber mulching and geotextile material is used for agriculture to minimize soil erosion. It prevents the direct exposure of soils to winds. In addition to erosion protection, organic mulch protects the moisture content in the soil and improves the soil structure.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Avoid overgrazing</span></b><span style="font-size: 14pt; line-height: 115%;">: it is allowed livestock to feed on pasture land till a certain limit to recover the vegetation again.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Add organic matter</span></b><span style="font-size: 14pt; line-height: 115%;">: Organic matter is able to glue small soil particles together to form large aggregates. So soils cannot be detached from the land. Compost can be added as the organic matter.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; text-indent: -0.25in;"> <!--[if !supportLists]--><span style="font-size: 14pt; line-height: 115%;">4)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14pt; line-height: 115%;">Maintain vegetation cover</span></b><span style="font-size: 14pt; line-height: 115%;">: The root systems of the plant helps to hold the soil particles in the places. They secrete glues which are helped to bind fine soil particles into large aggregates. Thereby they protect soils against water erosion. Thick vegetation cover prevents reduces wind velocity and does not allow it to contact the soil. Thereby it protects the soil against wind erosion.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 0.75in;"> <br /></div> <div class="MsoNormal"> <span style="font-size: 14pt; line-height: 115%;"><span style="font-size: 14pt; line-height: 115%; text-indent: -0.25in;">5)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><b style="text-indent: -0.25in;"><span style="font-size: 14pt; line-height: 115%;">No-tillage or conservation tillage</span></b><span style="font-size: 14pt; line-height: 115%; text-indent: -0.25in;">: Conservation tillage means to increase crop yield while taking actions to protect the soil against wind erosion and water erosion. Here tillage is not used from sawing to harvest or use minimum tillage.</span> <o:p></o:p></span></div>

Soil Erosion, Its Impacts and Conservation

Soil erosion refers to as the movement of soil particle form one place to another place. It is a natural process . It occurs at relativ...

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Biofertilizer for Sustainable Agriculture

<div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJGodkQ9eb6d71oliO5rY761UQkJ7M9ATvv_KybmFKyYtBfB6cr1IMWaKi4hYSde36WQrbNjKB7jytJySh3j5f3EpcWLcu5SZYPGnXGnFKPUXMq6QdsG_wCMiPFnkwb9A-4pDO5l9bpAyR/s1600/img.jpg.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="524" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJGodkQ9eb6d71oliO5rY761UQkJ7M9ATvv_KybmFKyYtBfB6cr1IMWaKi4hYSde36WQrbNjKB7jytJySh3j5f3EpcWLcu5SZYPGnXGnFKPUXMq6QdsG_wCMiPFnkwb9A-4pDO5l9bpAyR/s640/img.jpg.png" width="640" /></a></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;">Biofertilizer refer to as <b>the use of living microorganisms to provide primary nutrients and increase the growth of plants</b>. </span></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;">The microorganisms may inhabit in the rhizosphere or inner or surface plant tissues. In here, biochemical reactions of microorganisms are supported in the agriculture to increase the yield. They improve the nutrients availability to the plants. Due to the negative consequences of chemical fertilizers, the farmers tend to use biofertilizers for their crop production.<o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;">Biofertilizer are divided into three groups as follows:<o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l0 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Phosphorous fertilizers: It is used to optimize the phosphors level in the soil. It does not depend on the crop to be grown.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l0 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Nitrogen fertilizers: It is used to optimize nitrogen level in the soil. Since nitrogen requirements vary with the soil type, types of nitrogen fertilizer depend on the type of nitrogen fertilizers.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpLast" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l0 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Organic fertilizers: the biodegradable organics including animal and plant waste is degraded by aerobic respiratory microorganisms. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpLast" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l0 level1 lfo1; text-indent: -.25in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;">The types of biofertilizers are discussed below. <o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <b><span style="font-size: 14.0pt; line-height: 115%;">Nitrogen fixers</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Nitrogen is considered as a primary nutrient for plant. Even though the nitrogen accounts for 78% of atmosphere gas content, plant cannot absorb directly nitrogen from the atmosphere.  Nitrogen is released into soil trough decomposition of organic matter. Some microorganisms present in the soil are also able to fix atmospheric nitrogen.  <o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l1 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Free living bacte</span></b><span style="font-size: 14.0pt; line-height: 115%;">ria: they inhabit in the soil. They do not form mutual beneficial symbiotic relationship with plants roots.  Bacteria with different oxygen requirements are available to fix nitrogen. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.5in; mso-add-space: auto; mso-list: l1 level2 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><i><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">a.<span style="font-size: 7pt; font-stretch: normal; font-style: normal; font-variant-numeric: normal; line-height: normal;">     </span></span></i><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Ex: Aerobic: <i>Azotobacter<o:p></o:p></i></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 2.0in; mso-add-space: auto; mso-list: l1 level3 lfo2; mso-text-indent-alt: -9.0pt; text-indent: -2.0in;"> <!--[if !supportLists]--><i><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;"><span style="font-size: 7pt; font-stretch: normal; font-style: normal; font-variant-numeric: normal; line-height: normal;">                                                                                      </span>i.<span style="font-size: 7pt; font-stretch: normal; font-style: normal; font-variant-numeric: normal; line-height: normal;">      </span></span></i><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Anaerobic: <i>Clostridium polymyxa <o:p></o:p></i></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l1 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Symbiotic fixers</span></b><span style="font-size: 14.0pt; line-height: 115%;">: They from mutual beneficial symbiotic relationship with roots of legumes. The plant tissues make nodules where the symbiotic bacteria inhabit. They fix atmospheric nitrogen into ammonia. The ammonia is available when plant roots die or legume plants are buried directly as the cover crop.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpLast" style="margin-left: 1.5in; mso-add-space: auto; mso-list: l1 level2 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><i><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">a.<span style="font-size: 7pt; font-stretch: normal; font-style: normal; font-variant-numeric: normal; line-height: normal;">     </span></span></i><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Ex: <i>Rhizobium<o:p></o:p></i></span></div> <div class="MsoNormal" style="margin-left: .5in; text-indent: .5in;"> <br /></div> <div class="MsoListParagraph" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l1 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Symbiotic cyanobacteria</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Cyanobacteria are one of the photosynthetic organisms. Some of them are able to fix atmospheric nitrogen. They form symbiotic relationship with roots of plant including <i>Cycads, </i>liverworts and <i>Azolla</i>. In addition to nitrogen, they add organic matter to the soil through their photosynthesis. <o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in; text-indent: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;">Ex: <i>Anabaena</i> and <i>Nostoc<o:p></o:p></i></span></div> <div class="MsoNormal" style="margin-left: .5in; text-indent: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;">         But among them<i> Azolla- Anabaena </i>relationship fixes more nitrogen compare to the legume plants so aquatic environments like rice fields use <i>Azolla- Anabaena</i> to increase the yield. <o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <br /></div> <div class="MsoNormal" style="margin-left: .5in;"> <b><span style="font-size: 14.0pt; line-height: 115%;">Phosphorous solubilizing bacteria</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Phosphorous is also essential nutrient for plant. Phosphorous availability for plant determines solubility and concentration of Phosphorous ions. It is in insoluble forms which is unable to absorb into plants. Inorganic Phosphorous is added to soil by weathering of parent rock. Organic Phosphorous is added to the soil by decomposition of organic matter. The Phosphorous solubilizing bacteria convert the insoluble Phosphorous into soluble Phosphorous which can be absorbed by plants.<o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in; text-indent: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;">Ex: <i>Clostridium polymyxa, Bacillus, Enterobactor<o:p></o:p></i></span></div> <div class="MsoNormal" style="margin-left: .5in; text-indent: .5in;"> <br /></div> <div class="MsoNormal" style="margin-left: .5in;"> <b><span style="font-size: 14.0pt; line-height: 115%;">Mycorrhizae</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Some fungi found in the soul form mutual beneficial symbiotic relationship with roots of higher plants. The formation of Mycorrhizae is an infection to the plants. Fungi spores germinate near the vicinity of the root zone. Fungal hyphae penetrate and develop into the cortex of the roots. They show filamentous growth on the root surface. The fungal hyphae from arbuscule which is finely divided hyphae. It acts as the nutrients exchange interface between plant and fungal hyphae.  Those fungi association help plants to absorb nutrients in large area while plant provides organic food for them. It helps to correct the phosphors level of plants. It absorbs phosphors from large area and makes them soluble for the plant absorption. In addition to phosphorous uptake, Mycorrhizae secrete growth hormones for plants which are able to accelerate the growth. They promote the symbiotic nitrogen associations. <o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l3 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-family: Symbol; font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Symbol; mso-fareast-font-family: Symbol;">·<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">        </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Use of Biofertilizer is more advantageous over chemical fertilizers as follows. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l3 level1 lfo3; text-indent: -.25in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l2 level1 lfo4; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Biofertilizer are required in small quantity: small sized Inoculum of microorganisms is used to inoculate the seeds or plants surfaces. As the living microorganisms are used as the Biofertilizer, small number of microorganism can reproduce and form large colonies. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l2 level1 lfo4; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Increase yield: They are able to increase yield 15-30% by providing essential nutrients. Nutrients availability directly affects the yield. The increasing of yield also varies with type of biofertilizers because capability of different microorganism differs in the nutrients. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l2 level1 lfo4; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Reduce pollution: The farmers tend to add chemical fertilizers in large quantities as they intend increase yield through increasing nutrients availability. But plants absorb nutrients till certain extent. Excess nutrients remain in the soil. They are washed away by runoff. It causes eutrophication in aquatic bodies. But biofertilizers such as</span> <span style="font-size: 14.0pt; line-height: 115%;">Mycorrhizae are capable of absorbing phosphorus in large area so no need of excess chemical fertilizers to be added.<o:p></o:p></span></div> <br /> <div class="MsoListParagraphCxSpLast" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l2 level1 lfo4; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">4)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Improve soil structure: fungal hyphae help to bind small soil particles together into large aggregates. Thereby it increases the soil porosity. So water can more easily drained thorough the soil. It also increases the water holding capacity of the soil.<o:p></o:p></span></div>

Biofertilizer for Sustainable Agriculture

Biofertilizer refer to as the use of living microorganisms to provide primary nutrients and increase the growth of plants .  The micr...

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Ecotourism and Its Environmental Impacts

<div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhJlEnDbNSPRyQrv-96dLM1EgQrnhJklq0ZNoERia3pKwYpMgo9Wzy7bDwjX3HLwMhlNSoRjGpDrmrhzPeDjnI4kII952KBT9x3pRzytBI2pU5rgZuz5zhirCMbX9KxV6uAaUqbUhyWuVj7/s1600/img.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhJlEnDbNSPRyQrv-96dLM1EgQrnhJklq0ZNoERia3pKwYpMgo9Wzy7bDwjX3HLwMhlNSoRjGpDrmrhzPeDjnI4kII952KBT9x3pRzytBI2pU5rgZuz5zhirCMbX9KxV6uAaUqbUhyWuVj7/s640/img.jpg" width="640" /></a></div> <div class="MsoNormal" style="margin-left: .5in;"> <b><span style="font-size: 14.0pt; line-height: 115%;"><br /></span></b></div> <div class="MsoNormal" style="margin-left: .5in;"> <b><span style="font-size: 14.0pt; line-height: 115%;">Ecotourism is “Responsible travel to natural areas that conserves the environment and improves the well-being of local people." <o:p></o:p></span></b></div> <div class="MsoNormal" style="margin-left: .5in;"> <b><span style="font-size: 14.0pt; line-height: 115%;">                                                                        (TIES, 1990)<o:p></o:p></span></b></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;">Ecotourism is initiated with approaches to minimize the negative impacts of traditional tourism on the environment and enhance the cultural interaction of local people with tourists.  The governments can increase the awareness of local people and gain support from them for conservation of regional natural resources. While conserving the nature, ecotourism provides good income for governments and rural people.<o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <b><span style="font-size: 14.0pt; line-height: 115%;">Principles of Ecotourism</span></b><span style="font-size: 14.0pt; line-height: 115%;">: It is based on conservation, communities, and sustainable travel.<o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 75.0pt; mso-add-space: auto; mso-list: l3 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-family: Symbol; font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Symbol; mso-fareast-font-family: Symbol;">·<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">        </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Advantages of ecotourism can be discussed as follows.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 75.0pt; mso-add-space: auto; mso-list: l3 level1 lfo2; text-indent: -.25in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l2 level1 lfo4; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Environmental Conservation</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Ecotourism help to conserve all types of ecosystems including forests, coral reefs and mangroves. The governments tend to preserve the existing natural ecosystems and reforestation of the deforested area. Tourists and local communities are encouraged to conserve ecosystems. The taxes based on tourism, enters fee and donation are directed as funding on conservation actions, reestablishments and recover the ecosystem damage due to the tourism. Most tourists interest and join voluntarily for the conservation programs including sea turtle conserving program. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l2 level1 lfo4; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Enhance the living standard of the local community</span></b><span style="font-size: 14.0pt; line-height: 115%;">: ecotourism give direct employment for the rural people. They can find their job opportunity from transport, tourist hotels, guidance, conservation programs and constructions. The rural people can start their self-employment without joining directly into the ecotourism. They can open stores and sell local delicious foods. Tourists prefer to buy clothes, juallary, music instruments and bags which are made from local materials. Infrastructure is developed to attract more tourists which are results in indirect the development in the rural area. The construction of roads, drinking water, electricity, health facilities improve the</span> <span style="font-size: 14.0pt; line-height: 115%;">living standards of rural communities. The volunteers in the groups of tourists are willing to help local people to improve their health and education. They may conduct educational programs and clinic. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l1 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-family: Symbol; font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Symbol; mso-fareast-font-family: Symbol;">·<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">        </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Although ecotourism provides lots of benefits it is also associated with some disadvantages due to the misbehavior of both tourists and local communities and poor management as follows.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l1 level1 lfo1; text-indent: -.25in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoListParagraphCxSpLast" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l0 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Habitat degradation and fragmentation</span></b><span style="font-size: 14.0pt; line-height: 115%;">: construction of roads, accommodations and other infrastructures distrusts the habitats and ecosystems. The animals go through to roads are hit and killed by the vehicles carrying tourists. Construction may remove the vegetation that offers food, shelter and breeding places for native animal communities. <o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <br /></div> <div class="MsoListParagraph" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l0 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Threaten the animal biodiversity</span></b><span style="font-size: 14.0pt; line-height: 115%;">: The tourists tend to hunt in natural forests and fish in the coral ecosystems. It may leads to overexploitation and threatens the native and endemic animal species. Thereby it reduces the local animal and plant diversity. The annoying actions including noising of tourists disturb the animal behavior. Most of the animals do not like to contact with people so that those kind animals tend to moves another suitable ecosystem where the human influence is still not a problem. The fire camps within forested areas disturb the pathways of nocturnal animals including elephants, lions and ant eaters. Wild animals tend eat the remaining of food thrown away by tourists. These foods may be wrapped in polythene bags which are accumulated and block the digestive tracks of animals including the elephants. They left over plastic water bottles, aluminum cans which are not easily biodegradable and remain within the wild environment and affect the existence of plant animal communities. The propeller cuts of boat hit and kill the animals live in the coral ecosystems. <o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .5in;"> <br /></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l0 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Aquatic pollution</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Unregulated boat riding brings serious environmental problems. They increase the turbulence and reduce light penetration through increasing turbidity at the most of time. So it kills the plants and algal communities in bottom of the sea. The gases releases due to fossil fuel burning from boat are toxic to plant and animal communities. It has been damaged and killed the entire coral reef communities in most area of the world. Poorly maintained boats leak oil into water. These oil deposits in the feathers on the sea birds which make them unable to fly. Oil decreases the light penetration through the water. It reduce dissolving oxygen through the oil water interface.it disturbs natural temperature lowering and establishing mechanisms. Thereby it increases temperature of water. Oil pollution is extremely cost to remove by mechanical methods. Propeller of boat damages and cut the aquatic vegetation including sea grasses and seaweeds.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l0 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">4)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Soil disturbance</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Constructions of roads disturbs the soil. It left soil more vulnerable to wind and water erosion. Deposition of eroded soil in aquatic systems threats the aquatic animal and plant life. Use of vehicles for transporting tourists such as safari jeeps cause soil compaction in forested area which result in water logged condition because it reduces the infiltration capacity of soil.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l0 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">5)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Introduction of alien invasive species</span></b><span style="font-size: 14.0pt; line-height: 115%;">: alien invasive species are unintentionally introduced trough the ecotourism. The vehicles that transporting tourists from urban areas to rural areas or long distance supports to introduction of alien invasive species into native areas. The vehicles that are used for construction purposes are another source of introduction of alien invasive species. The tourists transporting and recreational ships and boats also cause spread of alien invasive species in aquatic ecosystems. Recreational boats act as the major spreading agent of <b><i>Dreissena polymorpha</i></b> between lakes and rivers within Europe. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l0 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">6)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Forest resources exploitation</span></b><span style="font-size: 14.0pt; line-height: 115%;">: The large trees grown in the forests are fall down for constructing tourists’ hotels. Loss of trees directly affects the existence of the ecosystem as animal community interacts with them. Tress acts as a habitat for many animal species. Pollinators and seed dispersals directly depend on tree for their survival. Birds, animals and insects find their breeding places, nesting places in large trees. Some tourists tend extract forest resources illegally. Some collect bird eggs, small reptiles, butterflies and moths, resins from trees, fungal species and piece of corals.  They collect and bring them into their countries for genetic exploitation.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.0in; mso-add-space: auto;"> <br /></div> <br /> <div class="MsoListParagraphCxSpLast" style="margin-left: 1.0in; mso-add-space: auto; mso-list: l0 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">7)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Social impacts</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Young children in rural and coastal areas tend to leave the school and join to ecotourism to earn money. Tourism persuades small children and girls to employ as sex workers. Thereby HIV aids transmit from the foreign tourists to local people. Ecotourism create a way to transport drugs into local communities which lower the health and income of people.<o:p></o:p></span></div>

Ecotourism and Its Environmental Impacts

Ecotourism is “Responsible travel to natural areas that conserves the environment and improves the well-being of local people." ...

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First Generation Biofuels

<div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhJE695hYXDAz9meeuG41W50YKJC9X1mwuKG3-0cOvJrxwu_MsIBKfzjrjj5jX0hKuzRUVKkhy1rVGGlTOqmcIC7_mJ5Vo4rT2oJ2FBQeibMohD9zwk4NfE433kKem3xx-WLV_-LFt-lcMM/s1600/img.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="426" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhJE695hYXDAz9meeuG41W50YKJC9X1mwuKG3-0cOvJrxwu_MsIBKfzjrjj5jX0hKuzRUVKkhy1rVGGlTOqmcIC7_mJ5Vo4rT2oJ2FBQeibMohD9zwk4NfE433kKem3xx-WLV_-LFt-lcMM/s640/img.jpg" width="640" /></a></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">Biofuels are introduced as the renewable energy resource. Biofuels are borne with high potential to minimize the greenhouse gas emission compare to the fossil fuels. <b>The feedstock is used for first generation biofuels production can be also used as the food crops</b>. Sun flower, <i>Jatropha</i>, soy bean, pram, sugar cane, wheat, sugar potato and beat are examples for plants that have been used. A part including seeds, fruits or whole food plant can be used for biofuel production. Bioalcohol, biodiesel, green diesel, biogas are produced as the first generation biofuels. <o:p></o:p></span></div> <br /> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Bioalcohol</span></b><span style="font-size: 14.0pt; line-height: 115%;">: It is produced from the sugar and starch rich food crops. Sugar is fermented into alcohol by microorganisms and enzymes. Bioalcohol includes methanol, ethanol and propanol.</span></div> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj7AN3IZ6U5Hahq2PJLUcy2f_Y-wvoj8l-Ce16Gskopv5MJCNUn47iGD2HqaTgyf2jo7ir7BQvgvDP26hGOqAgv3K6XoKo9W-biN2qvhDi2rdORoaO7hf9C01CC9bksrfNNSJw_nA3X36pC/s1600/16832272_1727013927610473_5397295824119446341_n.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="180" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj7AN3IZ6U5Hahq2PJLUcy2f_Y-wvoj8l-Ce16Gskopv5MJCNUn47iGD2HqaTgyf2jo7ir7BQvgvDP26hGOqAgv3K6XoKo9W-biN2qvhDi2rdORoaO7hf9C01CC9bksrfNNSJw_nA3X36pC/s640/16832272_1727013927610473_5397295824119446341_n.jpg" width="640" /></a></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">Cereal grains are crushed to release starch. Then these starches are subjected to process called hydrolysis to convert the cellulosic biomass into fermentable sugar. Yeast is added and the solution is heated. Invertase acts as the catalyst and breaks down the sucrose into glucose and fructose. Then these glucose and fructose reacts with another catalyst, zymase to produce ethanol. Since the ethanol contain large fraction of water, the distillation process is used to remove water and increase the concentration of ethanol compare to the initial solution. The mixture of ethanol and water is heated. As the boiling point of ethanol is lower than the water, it is converted into vapor phase. Then ethanol is condensed and separated from the water. Ethanol can be used directly in the gasoline engines.<o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Biodiesel</span></b><span style="font-size: 14.0pt; line-height: 115%;">: it is produced from the transesterification of alcohol and oil which is extracted from the crop plants.  A mixture of methanol or ethanol and biomass containing fatty acids are mixed and reacted together in the presence of NaOH as the catalyst. Biodiesel is similar in the composition to fossil diesel. Biodiesel are fatty acid methyl or ethyl esters. Animal flat, sun flower, soy bean, pram, vegetable oil, algae are used as the raw materials for biodiesel production. Biodiesel can be used in directly in petroleum engine of mixture of biodiesel and petroleum engine can be used.<o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Green diesel</span></b><span style="font-size: 14.0pt; line-height: 115%;">: It is produced by using refinery methods. Large molecules found in vegetable oil are break down into small hydrocarbon chains at elevated temperature and elevated pressure in the presence of catalysts. <o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Biogas</span></b><span style="font-size: 14.0pt; line-height: 115%;">: It is produced through the digestion of biomass in an anaerobic digester by anaerobic microorganisms. Whole crop plants or a part of the plant, residues of crop plant and residues of other biofuel production can be used as the feedstock for anaerobic director. Here biomass is converted into methane which combustible gas. It can be directly used in vehicle engines or cooking ovens. The residue form the anaerobic digester can be further processed and used as a biofuel or can be applied as a fertilizer for agriculture. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpFirst" style="mso-list: l2 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-family: Symbol; font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Symbol; mso-fareast-font-family: Symbol;">·<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">        </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Use of first generation biofuel has advantages over fossil fuels as follows.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="mso-list: l0 level1 lfo2; text-indent: -.25in;"> <br /></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l0 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Greenhouse gas mitigation</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Biofuels are burned more cleanly than fossil fuels which result in leaving small quantity of greenhouse gas emission. Use of biodiesel in vehicle is able to reduce the greenhouse gas emission by 20-60%. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l0 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Renewable energy source</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Biofuels can be replenished within short time period. Fossil fuel is limited in the supply. It takes millions of years to generate fossil fuel to generate in the underground. So fossil fuel cannot replenish within short time period. Therefore biofuels are one of the best solutions for limited fossil fuels. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l0 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Provide employment for rural communities</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Preparation of land, sawing, harvesting and processing of biofuels give opportunity form rural people to earn considerable income. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l0 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">4)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Economic security</span></b><span style="font-size: 14.0pt; line-height: 115%;">: The countries where the fossils fuels were not generated as a natural resources have to export crude oils and other associated products from Middle East countries. So these countries have to pay extremely high prices for purchase crude oil and transport them into their country. The processing crude oil into fossil fuels such as diesel and gasoline is also costly. Therefore as countries can grow crops for biofuel production within their countries, it saves money of them. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; mso-add-space: auto;"> <br /></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l2 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-family: Symbol; font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Symbol; mso-fareast-font-family: Symbol;">·<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">        </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Although biofuels are renewable energy source, it also has certain negative consequences on society, environment and economic as follows:<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l2 level1 lfo3; text-indent: -.25in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l0 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Threat to food security</span></b><span style="font-size: 14.0pt; line-height: 115%;">: The use of food crops for biofuel generation cause the increase of the price of food and animal feed. The lands available for agriculture and fertilizers are used for the growing crops for biofuels. Thereby it reduces the agricultural production in the world. The world food supply is restricted for the developed countered for their consumption and biofuel production while poor country surfing from long time starving.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l0 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">High production cost</span></b><span style="font-size: 14.0pt; line-height: 115%;">: More money has to be pumped into preparation of lands, planting crops, application of fertilizers and pesticides, harvestings and processing.it can be manual or mechanical. The use of machines is more effective and cheap even though its capital cost is high. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l0 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Contribution to greenhouse gas emission is considerable</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Even though the burning of biofuel is more clean, use of machines for preparation of lands, sawing, harvesting is contributed to the greenhouse gas emission.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l0 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">4)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">The price of the biofuel is expensive</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Due to the high production cost, the biofuels cannot be sold at reasonable price. Therefore most of people still rely on fossil fuels. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l1 level1 lfo1; text-indent: -.25in;"> </div> <div class="MsoListParagraphCxSpLast" style="margin-left: 1.25in; mso-add-space: auto; mso-list: l0 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">5)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><b><span style="font-size: 14.0pt; line-height: 115%;">Reduce biodiversity</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Growing crops for biofuel generation is often monoculture. So it has relatively low biodiversity.  Forested areas have to be cleared to be growing food crops. So it disrupts the food webs and reduces the regional biodiversity. With the growing of crops, animals, microorganisms and plants pests can be introduced. There is high probability to spread those pests into natural ecosystems and displace the native species. The scientists tend to introduce genetically modified plant spices which are insect pest resistant and increase in energy content for biofuel production. Those GMO can spread into natural ecosystems and cross with wild species. It may cause genetic degradation.  <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="mso-list: l1 level1 lfo1; text-indent: -.25in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoListParagraphCxSpMiddle" style="mso-list: l1 level1 lfo1; text-indent: -.25in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <br /></div>

First Generation Biofuels

Biofuels are introduced as the renewable energy resource. Biofuels are borne with high potential to minimize the greenhouse gas emissio...

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Riparian Buffer and its Environmental Benefits

<div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiCHXUmoF8MKWE3RuV_Ew5J0tdTFHPp3tML0rw7Y4IrZI2bb-JZptK42RDHwsH2xTnT_bH5XnYog8tCebaW2WBDPlW3znputb-SZGWosjlLPufR7GJXlYYjt9Rei7-gliFl9vWAIXOIqYCi/s1600/img.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="360" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiCHXUmoF8MKWE3RuV_Ew5J0tdTFHPp3tML0rw7Y4IrZI2bb-JZptK42RDHwsH2xTnT_bH5XnYog8tCebaW2WBDPlW3znputb-SZGWosjlLPufR7GJXlYYjt9Rei7-gliFl9vWAIXOIqYCi/s640/img.jpg" width="640" /></a></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;"><br /></span></b></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Riparian buffer are the rows of grasses or trees planted along the bank of rivers and streams</span></b><span style="font-size: 14.0pt; line-height: 115%;">. It is one of the agroforestry systems. Riparian buffers act as the interface between adjacent terrestrial and aquatic ecosystems. They are designed to protect the river or stream banks, control flood and minimize the non-point aquatic pollution.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Planting zones: </span></b><span style="font-size: 14.0pt; line-height: 115%;">Riparian buffer zoned is divided into sub zones from land towards aquatic bodies as upland zone, transitional zone, overbank zone, bank zone and toe zone. Large trees and shrubs are planted in both upland zone and transitional zones. In the</span> <span style="font-size: 14.0pt; line-height: 115%;">overbank zone, Small to medium size shrubs is found.  Plants with flexible stems and creeping stems including glass are plant in the bank zone so that plant are not damaged by the extend flood.  Emergent plant species including sedges are found in the toe zone. Large trees are not planted near zone aquatic body because they are not able to tolerant to large flood.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;"> Buffer width:</span></b><span style="font-size: 14.0pt; line-height: 115%;">  The width of the riparian buffer is the major important factor that affects the effectiveness of the buffer. Welsch has recommended that width of the riparian buffer should be 90feets on both sides of the river. But width of the buffer depends on the adjacent land area and land uses. Small stream with limited input from adjacent land area should have a small buffer width. But large stream with large input from adjacent area should have a large buffer width to protect the stream. Adjacent lands may be used for agriculture, commercial or residential area.  Agricultural lands with good management and maintain requires narrow width buffers. Types and composition of soil also determines the width of the riparian buffers. Soils with well drained have high rate of infiltration so it reduces the runoff. Therefore it requires riparian buffer with narrow width. But poorly drained soils have low rate of infiltration so it increases the runoff. Therefore it requires riparian buffer with wider width.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Plant section</span></b><span style="font-size: 14.0pt; line-height: 115%;">: characteristics of the river or stream bank determine the plants that needed to grow. Most of the plant cannot survive and grow within a certain range of environmental conditions such as pH, soil air, soil moisture, and soil type and soil texture. But some are able to grow in extreme conditions including water logged conditions, acidic or basic pH. Some grow well even in sandy soil where the moisture and nutrient retention is relatively low. Therefore the plants that are planted in the riparian buffer zone are able to tolerate water logged conditions, excess nutrients and sediments and even withstand in sandy or clay soil. A mixture of pants that offer fruits, fuel, fertilizer, timber, medicine and nesting places for birds and other animals can be selected.<o:p></o:p></span></div> <div class="MsoListParagraph" style="mso-list: l0 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-family: Symbol; font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Symbol; mso-fareast-font-family: Symbol;">·<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">        </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Riparian buffer zones help to enhance quality of aquatic ecosystems while giving other kind of ecological, economic and social benefits as follows.<o:p></o:p></span></div> <div class="MsoListParagraph" style="mso-list: l0 level1 lfo1; text-indent: -.25in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Flood control</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Riparian buffers act as obstacle for incoming water through the surface of the land towards the streams. Thereby it slows down the surface runoff. The root systems of trees and grasses in the riparian buffers help to lower the river flow velocity. Their extensive root systems soak up the water in large quantity. Thereby it reduces the risk of flood. As significant flood is required for the maintaining of flood plains, refrain buffers help to keep the flood at moderate level.<o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Trap sediments</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Runoff from the poorly managed agricultural land brings lot of excess sediments. These sediments tend to deposit at the bottom of aquatic bodies. Thereby continuous addition of sediments decreases the available depth for aquatic life. These sediments deposits in the gill of the fishes which kill them. Pesticides, nutrients and heavy metals also bind and come with sediments so excess nutrients causes eutrophication in aquatic ecosystems. Pesticides and heavy metals tend to go through food webs and accumulate in plant and animal bodies which results in serve health problems or detrimental effect on the animal in the top of the food webs. Excess sediments are trapped by the extensive root systems of shrubs, grasses and trees in the riparian buffers .but when sediments is serious problem, larger portion of the total buffer system hat to be planted with grasses which are more effective in slow down flow of incoming water and trap the sediments. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Control pollution</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Nitrogen and phosphorus are the primary nutrients for aquatic plants and algae. But excess nutrients cause the sudden increase of the algal growth. It is referred to as eutrophication. Eventually eutrophication is able to kill the all aquatic life and convert the ecosystem into dead. So trees and shrubs in the riparian buffer are important to eliminate the excess nutrient from the incoming water. The extensive root systems of trees and shrubs absorb nutrient in large quantities for their growth. Roots of some plants are able to sequester excess nutrient in their roots. The anaerobic bacteria inhabits outside the rhizomes of roots are able to denitrification of excess nitrogen. After conversion of excess nitrate into nitrogen, it expels into the atmosphere. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Stream of river bank protection again erosion</span></b><span style="font-size: 14.0pt; line-height: 115%;">:  The extensive roots system of trees, grasses create a mat to hold the soil in a place. Roots absorb the water in large volumes from the bank so it is not allowed water content of the soil in the bank to reach to saturated level. Thereby it minimizes the risk of bank collapsing. Leaf litter from the buffer increases the roughness of the bank so it reduces the river flow velocity. Thereby it minimizes the ability of river flow to erode the bank.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Provide wildlife habitats</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Riparian buffers create the animal and plant communities with high diverse and productivity. Some animals only come to the riparian buffer for food, nesting and nursery while other inhabits as their permanent habitat.  Animals use trees and shrub as their nesting places. Wildflowers provide nectar for humming birds. Evergreen shrubs and tress serve as a winter cover for wild life. Riparian acts as the corridors for the wildlife. They support to link the habitats with same type of some animals. Migrating birds find fruits and insects in the riparian zones. The buffer zones offer nectar and host plants for certain butterflies and moths species. Salamanders dig the soil and put their eggs among the leaf litter in the floor of buffer zones. <o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Enhance the quality of aquatic habitats:</span></b><span style="font-size: 14.0pt; line-height: 115%;"> Riparian buffers provide fundamental food sources of food webs of aquatic ecosystems. Leaf litter falls into the water bodies are decomposed by microbes so that organic matter and nutrients become available for other plants and animals such as collectors and shredders. Macro invertebrates and small fishes also depend on this leaf matter. These macro invertebrates and small fishes are eaten by large fishes. In addition to food, riparian provides shelter for aquatic life. Shelter and wind blowing from the buffer zone help to lower the temperature and maintain within a stable range. Thereby it improves the oxygen solubility in the water. Broken branches provide better hiding places for macro invertebrates and small fishes to escape form their predators. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Aesthetic and recreational value</span></b><span style="font-size: 14.0pt; line-height: 115%;">: In addition to ecological values, riparian buffers attract the local and foreign tourists due to its fascinating surrounding. People use the aquatic ecosystem associated with the buffer zone for swimming, boat riding, walking, fishing and bird watching. The stream or river and the riparian buffer improve the regional landscape. The tourisms bring good income and development for the rural communities. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <br /> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Increase economic value</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Landholder can earn good income when their riparian buffer zones are well managed and maintained. In addition to protection of aquatic water bodies, the buffer zones provide firewood, fruits, medicines, tanning and dyes and honey produced by bees. After trees get mature, they can be cut for the woods, while replacing them by newly planted trees. They provide winter protection for livestock. They trap water which is even available under drought conditions for land. It reduces the spread of pest and diseases attack. Well managed buffer zone can be used for eco-tourism which gives high income.</span><o:p></o:p></div>

Riparian Buffer and its Environmental Benefits

Riparian buffer are the rows of grasses or trees planted along the bank of rivers and streams . It is one of the agroforestry systems. ...

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Weeds as Sustainable Resource

<div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgVuULyDwRkO1DcFNIEfxj3vFcen27mvOfdXH_oi1-yBKskAOOzZaGpKtx7FlJ6cny5nK6hNBOl7yh8pHeD_Kro8FrH-Wojq8NZbHINzMZlfZGdknZPsjniky1_BttGH30qd-4qm3-zf4aa/s1600/weeds.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgVuULyDwRkO1DcFNIEfxj3vFcen27mvOfdXH_oi1-yBKskAOOzZaGpKtx7FlJ6cny5nK6hNBOl7yh8pHeD_Kro8FrH-Wojq8NZbHINzMZlfZGdknZPsjniky1_BttGH30qd-4qm3-zf4aa/s640/weeds.jpg" width="640" /></a></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;"><br /></span></b></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Weeds are the plant that grows where it is unwanted or grow and spread fast and takes the place of native plants. <o:p></o:p></span></b></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;"><br /></span></b></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Effects of weeds</span></b><span style="font-size: 14.0pt; line-height: 115%;">: They are able to grow fast and spread in native areas. They compete successfully for light, space, water and nutrients with native plant species. They are more vulnerable to pest and diseases attack. Thereby they take place gradually of the native plants and reduce biodiversity. Alternation of plant community directly affects their pollinators and seed dispersal agents. Weeds cause the loss of the nesting places of native birds. So animal diversity is also gradually become reduced as they moves into new area or die. Weeds increase the cost of agriculture because once weeds have established, it is very difficult to eliminate it.  Some weed may cause allopathic effect. They produce toxic chemicals that interfere with metabolic pathways or suppress the growth native plants seedling within their vicinity of roots. Ex: <b><i>Chromalaena odorata.</i></b> Some are cause allergic reactions in humans. <b><i>Alternanthera philoxeroides</i></b>(</span> <span style="font-size: 14.0pt; line-height: 115%;">Alligator weed)is misused by people due to the same appearance with</span> <b><i><span style="font-size: 14.0pt; line-height: 115%;">Alternanthera sessils</span></i></b><span style="font-size: 14.0pt; line-height: 115%;"> but<b><i> </i></b>toxic to human.<o:p></o:p></span></div> <div class="MsoListParagraph" style="mso-list: l0 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-family: Symbol; font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Symbol; mso-fareast-font-family: Symbol;">·<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">        </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Although the weeds are often disadvantageous, they are useful in many ways. <o:p></o:p></span></div> <div class="MsoListParagraph" style="mso-list: l0 level1 lfo1; text-indent: -.25in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Erosion protection</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Weeds grow as a thick layer in the agricultural lands so it prevents wind contact with top soil particles. Thereby it reduces the erosion by wind. The weed have strong either fibrous or tap root system that hold the soil particles together. The secrete glues that bond soil particles together intro large aggregates. Thereby the weeds reduce the erosion by rain.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Add nutrients and organic matter</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Weed can be buried as a green manure crop with main crop so that its decompositions of its plant materials release nutrient and organic matter into the soil. <b><i>Chromalaena odorata</i></b> as a green manure crop, it adds large amount of nitrogen as its leaves are rich in nitrogen. If <b><i>Crotalaria retusa</i></b> is grown as a green manure crop, it adds directly nitrogen to the soil because it belongs to legume. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Leafy vegetable</span></b><span style="font-size: 14.0pt; line-height: 115%;">: <b><i>Amaranthus spinosus</i></b><i> </i>is perennial weed. It is often found in agricultural lands. It contains protein, minerals, and vitamins in large quantity so it is able to heal some health problems. Its higher fiber content is good for the health of digestive tract. It is rich in potassium which helps to lower the blood pressure. High concentration of vitamin A lower or stop the cataracts in eyes and keep the vision healthy. It contains amino acids which are not produced by human body and they increases calcium uptake. Thereby they bind tightly hair to the head so prevent the hair losses. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Feedstock for livestock</span></b><span style="font-size: 14.0pt; line-height: 115%;">: <b><i>Panicum maximum</i></b><i> </i>is a perennial shrub. It possesses a erect system<i>. </i>It is eaten by all classes of grazing livestock. Its young leaves are more palatable compare to the mature ones. In Vietnam, its leaves are used for fish feeding.<i> <b>Commelina diffusa</b> </i>is another weed which grows in wet areas. It is comprised with creeping stem. It grows as annual in temperate countries while it grows as perennial in tropical countries. In addition to feed, it gives water in large quantities. Thereby it reduces the water requirement for livestock.<o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Medicinal value: <i>Cyperus rotundus</i></span></b><span style="font-size: 14.0pt; line-height: 115%;"> is also known as nut grass. It grows as perennial. It has an underground stem.  It is used as an ingredient in traditional ayurvedic medicine.it helps to treat digestive problems, menstrual disorders and nausea. <b><i>Scoparia dulcis</i></b> is another medicinal herb in</span> <span style="font-size: 14.0pt; line-height: 115%;">traditional ayurvedic medicine. It grows as perennial. Its whole plant is boiled and drink for diabetes. In addition diabetes, it is used for treat eye disorders, ear disorders, menstrual irregularities and parasitic infections. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Economic important</span></b><span style="font-size: 14.0pt; line-height: 115%;">: weed has potential for been using as a feedstock for biofuel production. Growing energy crops increases the demand for land and nutrient available for world food production. It has to be pump money on growing them. But use of weed as a feedstock, it does not affect the agriculture. Cost of the biofuel production is lowered. Thereby customers can apply biofuel for their vehicles at reasonable price. It gives additional income for farmer.  It is one of best solutions for weed management other than environmental degrading methods. <b><i>Panicum maximum</i></b> is grown in Central America for bio alcohol production. Whole plant body of weed can be used as feedstock in anaerobic digester for methane production. Leaves of <b><i>Panicum maximum</i></b> is used for thatching. Its culms are used for basket manufacturing. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Ornamental and hedge plant</span></b><span style="font-size: 14.0pt; line-height: 115%;">: <b><i>Lantana camera</i></b> is perennial flowering plant.it is native to the tropical areas of America and Africa. But it now has included in 100 of world worst invasive plants. It possesses erect or subscandent stem. It grows individually in clumps or as dense thicket. It attracts and provides nectar for many species of butterflies and moths. But its spread into land which are used as pasture for livestock because it produces toxic substances that are able to kill livestock which is result in economic loss.  <b><i>Lantana camera</i></b> as a hedge plant, it helps to keep away livestock from gardens.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <br /> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Raw material</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Exactions from young twigs of <b><i>Eclipta prostrata</i></b> are used as a raw material for hair oil productions.it has ability promote the hair growth. <o:p></o:p></span></div>

Weeds as Sustainable Resource

Weeds are the plant that grows where it is unwanted or grow and spread fast and takes the place of native plants. Effects of weeds ...

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Algal Biofuels

<div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjpphTgMONiO5RTxSNQFXisVtxrq6hyphenhyphenI7Pm7Xfz0eozDp8MjOTYOh4MNzCbSpFx-DmcFdIcl919EH4yh5HekrhyQpNsdQU943hwh7BK0_I45E2ayhjg_Iy8eYqC4cqHmDsy8xjGAvYADgoT/s1600/img1.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="404" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjpphTgMONiO5RTxSNQFXisVtxrq6hyphenhyphenI7Pm7Xfz0eozDp8MjOTYOh4MNzCbSpFx-DmcFdIcl919EH4yh5HekrhyQpNsdQU943hwh7BK0_I45E2ayhjg_Iy8eYqC4cqHmDsy8xjGAvYADgoT/s640/img1.png" width="640" /></a></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">The world has paid attention towards renewable energy sources to overcome environmental issues and limited availability of fossil issues. Therefore use of algal biomass is recognized a one of best solution. The production of biofuel algae as the raw material is considered referred as the third generation fuel production. It is able to minimize or eliminate the negative impacts due to the first and second generation fuel production. Algal biomass production does not compete with food production in the world like first generation fuel and it does not threat to the food security.</span><u><span style="font-size: 48.0pt; line-height: 115%;"><o:p></o:p></span></u></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                        Algae biomass production does not involve with agricultural lands. It harvests high yield per unit area of land. Freshwater is not essential for algae production. Sea water and wastewater also can be used.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                        Both microalgae and microalgae are used for the algal fuel production. Microalgae are single celled algae that live as individual or colony. Oil extracted from microalgae is used for biodiesel production. Macroalgae with high sugar content in cell wall is used for bioethanol production via fermentation. Macroalgae are digested in an anaerobic digester for methane production. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Algae culture</span></b><span style="font-size: 14.0pt; line-height: 115%;">: It is the growth of algal biomass. Macroalgae are grown directly on the open sea. But most people tend to collect macroalgae from the sea and estuary rather than cultivation. Thereby it threats the ecosystem balance. Microalgae are grown in the specifically designed systems available in the land. It has to be supplied externally nutrients, light, carbon dioxide, water and stable temperature. Wastewater is provided in the form of nutrients. Open ponds and photo bioreactor are currently used for microalgae cultivation. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Open ponds:</span></b><span style="font-size: 14.0pt; line-height: 115%;"> It is constructed in the shape of circular or rectangular (raceway). It may large shallow or deep pond according the depth. The depths of open ponds varies from 1-100cm. water is mixing by using paddles or other mechanical devices. The bottom of raceways ponds are made of concrete or lined with plastic. Due to the low cost of plastic lined, raceways ponds may expand from few feet to thousand meters in length.</span> <span style="font-size: 14.0pt; line-height: 115%;">Circular ponds are oldest method of algal cultivation. A centrally located rotation arm is used to mix the water. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal" style="margin-left: .25in;"> <b><span style="font-size: 14.0pt; line-height: 115%;">Advantages of open ponds</span></b><span style="font-size: 14.0pt; line-height: 115%;">:<o:p></o:p></span></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: .75in; mso-add-space: auto; mso-list: l4 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Low per capital cost and operating cost<o:p></o:p></span></div> <div class="MsoListParagraphCxSpLast" style="margin-left: .75in; mso-add-space: auto; mso-list: l4 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Low energy requirement<o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .25in;"> <b><span style="font-size: 14.0pt; line-height: 115%;">Disadvantages of open ponds:<o:p></o:p></span></b></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: .75in; mso-add-space: auto; mso-list: l3 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Open pond system is less successful in the temperate countries which experience seasonal changes than tropical countries which do not experience seasonal changes. Because algae cannot grow during winter season so algae cultivation is restricted summer.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: .75in; mso-add-space: auto; mso-list: l3 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Sunlight causes the loss of significant amount of water due to the evaporation. Large surface area of pond expose to the sunlight. Therefore large amount of water is needed to operate the open pond system. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: .75in; mso-add-space: auto; mso-list: l3 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Open pond system produce low algal density per unit compare to the photo bioreactor. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: .75in; mso-add-space: auto; mso-list: l3 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">4)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">They are highly vulnerable to contamination by native species. Algae may subject to predatory attacks in the open pond system.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: .75in; mso-add-space: auto; mso-list: l3 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">5)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Light is not equally distributed throughout the open ponds because algae growth in the top layer of the water column restricts the light penetration to the bottom.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpLast" style="margin-left: .75in; mso-add-space: auto; mso-list: l3 level1 lfo2; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">6)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Loss of Carbon dioxide into the atmosphere from the ponds cannot be controlled. Carbon dioxide tends to expel into atmosphere through diffusion. As the temperature rises, it decreases the solubility of gas in the water. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpLast" style="margin-left: .75in; mso-add-space: auto; mso-list: l3 level1 lfo2; text-indent: -.25in;"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Photo bioreactor</span></b><span style="font-size: 14.0pt; line-height: 115%;">: they are the closed system of algal cultivation. Algae are grown in the closed</span> <span style="font-size: 14.0pt; line-height: 115%;">vertical vessels which are made of transparent material such as stainless stain, glass or polyethylene. It helps light to penetrate through it. But use of polythene is less durable and sensitive to environmental changes. Conditions within the reactors can be controlled. It leads to harvest maximum yield per unit of land area.  The photo bioreactor can be either operated as batch or continuous mode. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal" style="margin-left: .25in;"> <b><span style="font-size: 14.0pt; line-height: 115%;">Advantages:<o:p></o:p></span></b></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: .75in; mso-add-space: auto; mso-list: l2 level1 lfo4; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Photo bioreactor produce maximum yield per unit area because it offer larger area to volume ratio for the algal growth compare to the open ponds.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: .75in; mso-add-space: auto; mso-list: l2 level1 lfo4; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">As algae are grown in closer system, it restricts the evaporation of water.  Water requirement for the closer system is reduced. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpLast" style="margin-left: .75in; mso-add-space: auto; mso-list: l2 level1 lfo4; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">It save the space as it use vessel in the vertical position to grow so minimum land area can be used. Even it can be established in indoors. <o:p></o:p></span></div> <div class="MsoNormal" style="margin-left: .25in;"> <b><span style="font-size: 14.0pt; line-height: 115%;">Disadvantage:<o:p></o:p></span></b></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: .75in; mso-add-space: auto; mso-list: l0 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Its capital cost and operative cost is high. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: .75in; mso-add-space: auto; mso-list: l0 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">As it is operated under controlled conditions, it requires good care and maintenance. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpLast" style="margin-left: .75in; mso-add-space: auto; mso-list: l0 level1 lfo3; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Technicians should have proper knowledge on the system. <o:p></o:p></span></div> <div class="MsoNormal"> <br /></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Algae harvesting</span></b><span style="font-size: 14.0pt; line-height: 115%;">: After cultivation, increasing of concentration of algal biomass refer to as the algae harvesting. Nearly 20-30% of production cost has to be spending on the harvesting process. <b>Centrifugation, gravity filed, flotation and filtration</b> are the available techniques for algae harvesting.  Although centrifugation gives high algae cell density, it is energy intensive. Therefore approach like gravity settling is the best solution for the algal biofuel production. Algae biomass is deposited at the bottom of the settling tank under the process of flocculation. It can be used with or without chemical flocculants. But use of chemical flocculants is more efficient in biomass settling. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Algae processing</span></b><span style="font-size: 14.0pt; line-height: 115%;">: It is the process of the oil extraction from the algal biomass. Here two methods can be used. Algae biomass can be used directly for biofuel production or oil that is extracted from the alga biomass can be used for biofuel production. There are two methods available for extraction of oil form the algae biomass including solvent extraction and cell disruption to release the oil substances.  Algal biomass is dried first. Then later solvent extraction is used to separate the oil content form the algae. This oil can be used for biodiesel or green diesel production. Algal biomass can be disgusted in an aerobic digester to produce methane. It can be fermented into bioethanol by using microorganisms such as Yeast and enzymes. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Biodiesel derived from algae</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Oil content varies according to the type of algae. Therefore algae with the high oil content are selected to grow. Biodiesel is produced from algal oil and methanol by esterification. Biodiesel is similar in composition to fossil diesel. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Green diesel derived from algae:</span></b><span style="font-size: 14.0pt; line-height: 115%;"> it is produced by using a refinery method. The large oil molecules found in the algae are breakdown into small hydrocarbon chain that can be used directly in the diesel engine at elevated temperature and elevated pressure in the presence of catalyst. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Bioethanol derived from algae</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Here alga with high sugar content is used. Pretreatment is done to release the cellulose from the cell wall and breakdown them into fermentable sugar. It can be done using physical, chemical and biological methods. Use of biological method is relatively more beneficial. It does not need energy and chemical. But microorganisms that involve in breakdown of cellulose may not specific to cellulose they may degrade the glucose and fructose. Yeast is added externally and it produce methanol through fermentation. Then sucrose is breakdown into glucose and fructose by invertase. These glucose and fructose is converted into ethanol by zymase. Then ethanol is subjected to distillation. Because bioethanol still contains a large amount of water. So the mixture of water and ethanol is heated. The boiling point of ethanol is lower than that of the water. So ethanol is converted into vapor phase before water. It is condensed to spate from the water. It helps to increase the concentration of ethanol and clean it. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Benefits of algal fuel:<o:p></o:p></span></b></div> <div class="MsoListParagraphCxSpFirst" style="margin-left: .75in; mso-add-space: auto; mso-list: l1 level1 lfo5; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">1)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">It does not threat to the food production in the world. It need minimum land requirement compared to the biofuel production from food crops. It does not compete with nutrients available for agriculture because wastewater can be used to provide nutrients. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: .75in; mso-add-space: auto; mso-list: l1 level1 lfo5; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">2)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">It absorbs considerable amount of carbon dioxide for biomass production. So it helps to carbon sequestration. Thereby it reduces the greenhouse gas effect and global warming.<o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: .75in; mso-add-space: auto; mso-list: l1 level1 lfo5; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">3)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Use algae as a raw material for biofuel production can be used to produce a verity of fuels.<o:p></o:p></span></div> <div class="MsoNormal"> </div> <div class="MsoListParagraphCxSpLast" style="margin-left: .75in; mso-add-space: auto; mso-list: l1 level1 lfo5; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-size: 14.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">4)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">    </span></span><!--[endif]--><span style="font-size: 14.0pt; line-height: 115%;">Algae secretes oil compound that can be used directly as ingredient in bio fuel production so there is no technical challenges to pretreatment of lignocellulose biomass.<o:p></o:p></span></div>

Algal Biofuels

The world has paid attention towards renewable energy sources to overcome environmental issues and limited availability of fossil issue...

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