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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Compost as a Healthy Fertilizer

<div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjpotk8iqHPD39oQDanrVjaItscDMHSk8Dr1mWhJdexNiwnDTwyRUKJEuVsAWRLt6bpzDPrWBuM0LyRhWqikoKo9gUju2myK280LIDn2Bj-MqCxTdBC_GuO2orDVukkTeLxZb-WfS7Ift6m/s1600/compost.PNG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="326" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjpotk8iqHPD39oQDanrVjaItscDMHSk8Dr1mWhJdexNiwnDTwyRUKJEuVsAWRLt6bpzDPrWBuM0LyRhWqikoKo9gUju2myK280LIDn2Bj-MqCxTdBC_GuO2orDVukkTeLxZb-WfS7Ift6m/s640/compost.PNG" 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%;">Composting</span></b><span style="font-size: 14.0pt; line-height: 115%;"> <b>is produced as the result of decomposition of organic matter by microorganisms in the presence of oxygen under controlled conditions.</b> Compost has become a part of sustainable agriculture due to its ability to improve soil properties as well as yield. <o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Sources</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Biodegradable organics such as kitchen waste, garden pawn, organic fraction of municipal solid waste (MSW). Proper C: N ration must be maintained to enhance the microbial activities. Ideal C: N ratio for composting is 25:1. Carbon and nitrogen rich materials are mixed together to balance the C: N ratio .Hay, wood ashes, saw dust and dried leaves are added as the carbon sources.  Weeds, green manure such as <i>Grilicidia sepium, </i>fresh hay, and cow dung and fish emulsions can be added as nitrogen sources. <o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Shredding or branding</span></b><span style="font-size: 14.0pt; line-height: 115%;"> <b>materials</b>: Lager particles can be shredded into small particles which can be easily handled. It increases the available surface area for microorganisms. So duration of compost processing is reduced.  Air can move easily through the pile. It helps to distribute the heat uniformly throughout the pile. It reduces land requirement for compost pile. It can be more easily turned for aeration. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">Compost processing is done through three steps such as mesophilic, thermophilic and cooling and maturation phase. These three steps are dominated by different microbial communities. The temperature of the compost pile is related to the activity of the microorganisms. <o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Mesophilic</span></b><span style="font-size: 14.0pt; line-height: 115%;">: This is the initial step of composting. Rapidly degradable organic matter I degraded by mesophilic bacteria. Their activity is inhibited above 40◦C. Human and plant pathogens are destroyed above 55◦C. many microbes cannot survive above 60◦C. Composting also slow down at higher temperature. <o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Thermophilic</span></b><span style="font-size: 14.0pt; line-height: 115%;">: The second step of composting takes place at higher temperature. These high temperature acts as the accelerating factor for decomposing high strength organics such as protein, cellulose and lignocellulose. <o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Cooling and maturation phase</span></b><span style="font-size: 14.0pt; line-height: 115%;">: When organic matter is becoming limited, temperature of the compost file is gradually reduced. Mesophilic bacteria break down the remaining organic matter.<o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Physiochemical factor affecting the efficiency of the composting</span></b><span style="font-size: 14.0pt; line-height: 115%;">: <b>Oxygen</b> is consumed in large quantity particularly in the initial stage by microorganisms. Oxygen can be provided through aeration. Turning of material or embedded propagated pipes provides oxygen to the composting pile.The frequency of turning and level of aeration is governed by the type of material and present moisture content. Turning helps to bring material of outside the pile into center and decomposes the all of the materials in the pile.  Greater aeration accelerates the initial stage of composting and reduces the duration of compost processing. If suddenly oxygen supply of the pile is vanished, pile is turned into anaerobic. It produced odiferous ammonia. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                                 <b>Temperature</b> is another important factor that regulates the composting. Composting has two distinct temperature ranges. Mesophilic is up to 40◦C and thermophilic above 40◦C. Turning and heating prevents the overheating of the pile due to the microbial activities. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                                 Microorganisms need N, P and K as their <b>primary nutrients</b>. But in the composting C and N are taken into consideration. Ideal C: N ratio is 25:1. Low C: N ratio slows down the composting process. High C: N ratio cause unpleasant odor due to the release of excess nitrogen as ammonia. Therefore C: N ratio must be maintained as earlier discussed.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                                 <b>pH</b> of the composting pile varies with decomposition byproducts at each step. As result of acid accumulation, pH of mesophilic stage is reduced. Decomposition of acids release ammonia which increase the pH of composting. pH become neutral at final stage of composting. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                                 <b>Moisture</b> is important for the metabolic activities of microorganisms.  40-65% of moisture content must be maintained. Above 65% causes anaerobic conditions because water displaces the gas in the pores of the pile. <o:p></o:p></span></div> <br /> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Microorganisms</span></b><span style="font-size: 14.0pt; line-height: 115%;">: <b>Aerobic respiratory bacteria</b> are mainly employed in composting. Millions of them can be found in 1g of compost. They are diverse nutritionally group. They oxidized organic matter to ATP synthesis. These oxidation releases larges amount of heat. They are active during mesophilic stage. Most are died above 60◦ C and most of remaining forms endospores. They need oxygen level above 5%. <b>Actinomycetes</b> degrade the high strength organic matter such as cellulose, hemicellulose, lignin, starch and protein. They inhabit in the areas with moderate temperature in the compost pile. <b>Fungi</b> also are capable of breakdown of high strength organic matter as actionmycetes. They can be found outside of compost pile. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjApSFdpaZ0RmBtHSsrUCwvwRjYS6nSvz-YssoQxCPv5yorVHpwua6EoAR3qEzrInrBrx_pbQiZsgJEB45QwrjbdPdtVSPx41UwTd1kbsvxKGZt4DkVyy2DxwCygfJa2jYGV3nHa4HGud4F/s1600/compost2.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="466" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjApSFdpaZ0RmBtHSsrUCwvwRjYS6nSvz-YssoQxCPv5yorVHpwua6EoAR3qEzrInrBrx_pbQiZsgJEB45QwrjbdPdtVSPx41UwTd1kbsvxKGZt4DkVyy2DxwCygfJa2jYGV3nHa4HGud4F/s640/compost2.jpg" width="640" /></a></div> <div class="MsoNormal"> <br /></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Macroorganisms</span></b><span style="font-size: 14.0pt; line-height: 115%;">: In addition to microorganisms, large animals also support to compost processing. Larger animals including mites, millipedes, spider, flies and ants involve in the last stage of the composting. They help to mixing, chewing and digesting organic matter. They also shred the organic matter into small particles. Thereby organic matter can be easily digested by microorganisms. Their extra provides the nutrients for microorganisms in the compost pile. Protozoan can be found in the water droplet in the compost pile. They act as predatory organisms on bacteria. <o:p></o:p></span></div> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhapyQEk_vHdZfQyHQpg4sdne_w4Ywzuvj8pszkNhFjipglfpMfd5mmppvNb5joCqeGtHoA_IlD0ynrFbGMl2gSEp73NZUuI65m9iYpJ1Gt9W0Dm0D_FDO-haGhIFXJrQ9AIElT4gFcGeVu/s1600/compost1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="342" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhapyQEk_vHdZfQyHQpg4sdne_w4Ywzuvj8pszkNhFjipglfpMfd5mmppvNb5joCqeGtHoA_IlD0ynrFbGMl2gSEp73NZUuI65m9iYpJ1Gt9W0Dm0D_FDO-haGhIFXJrQ9AIElT4gFcGeVu/s640/compost1.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%;"><br /></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 composts</span></b><span style="font-size: 14.0pt; line-height: 115%;">:  Farmers tends to apply compost as fertilizer, soil conditioner and mulch.  Compost as fertilizer adds nutrients to soil. Slow decomposition of humus releases nutrient into soil. Quality and quantity of nutrient varies greatly with compost according to their initial sources. Compost as mulch is applied to the surface of soil. It protects the moisture content without allowing them to evaporation. It also suppresses the growth of weed which affects the agricultural crops. Compost as conditioner improves physical, chemical and biological properties of soil. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"> <b>Psychical properties</b>: Organic matter in the humus helps to bind the soil particles into aggregates. It increases the soil porosity which enhances the soil aeration. So plant root have ability take enough oxygen from the soil.  High porosity of soil increases infiltration. Thereby the surface runoff is reduced. It reduces soil bulk density. As soil particles binding together, it reduces the soil erosion due to the rain.  Due to the dark color of the humus, soil can absorbed more heat and maintain soil temperature and avoid temperature fluctuations. Thereby stable soil temperature encourages the seed germination.<o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Chemical properties</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Compost acts as a buffer agent and neutralizes variation in pH and salinity. Microorganisms in the humus provide the plant growth promoting substance such as vitamins and hormones. In addition to macronutrients such as N, P and K compost provides micronutrients. Compost provides more ion exchange sites to the soil in the purpose of negatively charged nutrient biding. Thereby it enhances the ion exchange capacity of soil.<o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Biological properties: </span></b><span style="font-size: 14.0pt; line-height: 115%;">high temperature<b> </b>that is generated by humus is able to kill pathogenic microorganisms. Humus encourages the growth of earth worms and other beneficial soil microorganisms. Predatory microorganisms such as protozoan are killed by microorganisms inhabit in the humus.<o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Environmental benefits</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Compost is produced from organic matter which is disposed as waste in most cases. So as a waste organic matter cause serve environmental problems. Unregulated releasing of organic waste cause aquatic pollution, eutrophication and degrading biodiversity. So local governments tend to collect the solid waste from their responsible area and separate the organic waste and process them into compost. So compost protects the environmental quality. It reduces the land requirement for disposal solid waste. It prevents the odor due to the anaerobic digestion, pathogens and pest problems. Quality of groundwater and surface water is preserved. <o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Economic benefits</span></b><span style="font-size: 14.0pt; line-height: 115%;">: Compost as organic fertilizer, it has a good price in the market. Rural people can process the composting plant individually in their home garden. They can apply compost for their agricultural crops while excess can be sold. Even in urban areas, compost can be produced by using compost bins. The vegetable and fruits that are grown using organic fertilizer are sold at higher prices compare to the vegetable and fruits grown using chemical fertilizers.<o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Disadvantages of composting</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: 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%;">Composting is slow releasing fertilizer of nutrients into the soil. So it is less suitable for agricultural lands that are growing annual crops. Humus releases nutrients even after cut off harvesting within fallow period. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpMiddle" style="margin-left: .75in; 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%;">Quality and quantity of nutrients varies greatly with compost. So it cannot be ensured that compost lonely act as perfect fertilizer and fulfill the all of the nutrient requirements. Chemical fertilizers release large quantity of nutrients that can be directly and readily absorbed by plants. But humus is needed to be further decomposed to release nutrients. <o:p></o:p></span></div> <div class="MsoListParagraphCxSpFirst" style="mso-list: l0 level1 lfo1; text-indent: -.25in;"> </div> <div class="MsoListParagraphCxSpLast" style="margin-left: .75in; 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%;">In most countries, organic fraction of municipal solid waste is used to produce compost. But even the organic waste contains loads of toxic materials which are unable to remove before or after processing like large materials such as polythene, Aluminum cans and broken glasses. Therefore addition of toxic substances including   heavy metals into agricultural soil cannot be avoided in the application of compost that is produced from MSW.<o:p></o:p></span></div>

Compost as a Healthy Fertilizer

Composting is produced as the result of decomposition of organic matter by microorganisms in the presence of oxygen under controlled c...

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Methylotrophy, Methanogenisis and Carbon Cycle

<div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Methylotrophy</span></b><span style="font-size: 14.0pt; line-height: 115%;">: There are some microorganisms those use methyl compounds as their substrate. These methyl compounds are oxidized into carbon dioxide. They oxidize these methyl compounds to take electron to run electron transport chain to synthesis ATP. The methyl compounds include methane, methyl ammine and methanol. <i>Methaylomonas</i> and <i>Methaylococcus</i> are the example for methyalotrophs.<o:p></o:p></span></div> <div class="MsoNormal"> <b><span style="font-size: 14.0pt; line-height: 115%;">Methanogens</span></b><span style="font-size: 14.0pt; line-height: 115%;">: It refers to as the generation of methane. Only few Arches including <i>Methanomonas</i> and <i>Methanococcus</i> are capable of generating methane. Eukarya, bacteria and other Archea are unable to generate methane.  <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                        Archea those live in anaerobic environments including ruminant of rumen, deep layer of soil, mud, bottom of waste dump site and intestine perform anaerobic respiration for their ATP synthesis. They use hydrogen as their substrate. They oxidize hydrogen into photon. This oxidation gives electron to run electron transport chain. They use the photon for their hydrogen acceptor in the electron transport chain. <o:p></o:p></span></div> <br /> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                       As they live in anaerobic environment, they have to use non oxygen terminal electron acceptors. So they use methyl compound including methanol, methyl amine and carbon dioxide. They reduce them into methane. Nearly 20% of world methane production is associated with the cattle farm areas. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg1NYKolPY9LuJQhPfd_buj1OIoXfeOKNlbVKoKELOouYcITZUC20I7zgLR2ErygnIBB6tVTSgks1MZRSGL7JUiwzKox6uUK8ub0_vvRE4K0C-9Cd8n_tDBXGfJlnCKeA9SjaFufSRHAwS-/s1600/img1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="281" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg1NYKolPY9LuJQhPfd_buj1OIoXfeOKNlbVKoKELOouYcITZUC20I7zgLR2ErygnIBB6tVTSgks1MZRSGL7JUiwzKox6uUK8ub0_vvRE4K0C-9Cd8n_tDBXGfJlnCKeA9SjaFufSRHAwS-/s400/img1.jpg" width="400" /></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%;">Methane is combustible gas which causes regular exploitation in the dump sites. It is also responsible for the greenhouse gas effects which cause global warming. Methane is used as an alternative fuel for fossil fuel in the world. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                               <b><u>Methanogens reduce the methyl compounds</u></b> into methane. So they cannot be labeled as methyltophs because <b><u>methylotrophs oxidize the methyl compounds</u></b> into carbon dioxide. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"> </span></div> <div class="MsoNormal"> <b><span style="font-size: 22.0pt; line-height: 115%;">Carbon cycle:</span></b><b><span style="font-size: 28.0pt; line-height: 115%; mso-no-proof: yes;"> </span></b><span style="font-size: 14.0pt; line-height: 115%; mso-no-proof: yes;">In anaerobic enmvirimnets, hyrdogen is avilbe as a result of fermentaion. Carban dioxide is availbe as byprodct of anaerobic repsiration. Methogen use these hyrogen as their oxidizable susbtrate and carbon dioxide as their terminal elctron acceptor. They produce methane. These metahne is used as the susbtate by methylotrophs. They oxidize them into carban dioxide. These carbon dioxide is fixed into organic compund by autrphs. In addtion to ayutrophs, methogens also use these carban dioxide as their terminal elctron aceptor and reduce them into methane. The organic matter is oxidized compleltly into caban dioxide by anerobic and aerobic respiratory bacteria. The organic matter is oxidized partially into small organics including alcohol, acids and aldehydes by fermentaitve bacteria under anaerobic conditions.  Occasionaly fermentative bacertia also complety oxidize organic matter into carbon dioxides. Those small oragincs are further oxidied into carbon dioxode by aerobic or anerobic repsiratory bacteria. </span><span style="font-size: 14.0pt; line-height: 115%;"><o:p></o:p></span></div>

Methylotrophy, Methanogenisis and Carbon Cycle

Methylotrophy : There are some microorganisms those use methyl compounds as their substrate. These methyl compounds are oxidized into carbo...

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Construction of Artificial Wetland for Wastewater Treatment

<div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                  Wastewater that are produced by industries are needed to treat in a proper manner before discharge into public sewer or receiving water bodies because industrial wastewater contain lots of harmful chemicals and pathogens. International and national standards must be followed at the discharge point of industries into receiving water bodies or public sewer. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                       Untreated wastewater or effluent cause severe environmental, social and economic problems when they are directly discharged without pretreatment. The release of wastewater without pretreatment stresses the public sewers. Untreated wastewater contain high pollution load which upset the biological processes. It exceeds the capacity of aerobic repertory microorganisms which involve in the degradation of organic matter in the aeration tank. It has to be given more retention time to reduce the undesirable qualities of the wastewater but it increases the cost of the treatment. It needs storage tank with high capacity which makes more land requirements to handle large wastewater volumes. Therefore pretreatment of industrial wastewater is essential before the discharge into public sewers.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                       Small scale industries and some of large scale industries tend to discharge their wastewater without treatment into receiving water bodies. These wastewater are able contaminate the ground water table which threats health of human. Release of untreated wastewater into surface drinking water sources discharge considerable amount of toxic metals and dyes which affects the ecosystems and human health. Industrial wastewaters that bring sewage as well contain loads of phosphate and nitrate which are capable of accelerating the growth of algae. With time, higher growth of the algae makes the aquatic ecosystem completely die. Some algal species are capable of producing harmful substances that are toxic to animals and human.  This kind of algal growth is known as <b>harmful algal broom</b>. <o:p></o:p></span></div> <span style="font-family: "calibri" , "sans-serif"; font-size: 14.0pt; line-height: 115%;">                 Most industries have a combined system for process both industrial wastewater and sewage wastewater which is generated by the sanitation activities of workers in the factories due to the cost effectiveness.</span><br /> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEggWWQ1QTCg_KEhAZPdo-4g6bOIwcwmoNqh5evGAJva3pqu43wapJ_OOMm4M0sswuuVoQzSgso1xXfOLZF4dIZic0dm2B-tcVzfa8zrRJ0nMsRaF4S5DqlolRCFB1g7rXNPAUvTo9-5MbnG/s1600/Capture.PNG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="640" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEggWWQ1QTCg_KEhAZPdo-4g6bOIwcwmoNqh5evGAJva3pqu43wapJ_OOMm4M0sswuuVoQzSgso1xXfOLZF4dIZic0dm2B-tcVzfa8zrRJ0nMsRaF4S5DqlolRCFB1g7rXNPAUvTo9-5MbnG/s640/Capture.PNG" width="635" /></a></div> <span style="font-family: "calibri" , "sans-serif"; font-size: 14.0pt; line-height: 115%;"><br /></span> <span style="font-family: "calibri" , "sans-serif"; font-size: 14.0pt; line-height: 115%;"><br /></span> <span style="font-family: "calibri" , "sans-serif"; font-size: 14.0pt; line-height: 115%;"><br /></span> <br /> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">Wastewater is collected from the all over the industry and passed through a metallic <b>bar screen</b>. It retains the large particles such as straws, glass pieces and sanitary napkins that can damage the pumps and other equipment in the treatment plant. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                           Oil from incoming wastewater is removed in the oil separation tank. <b>API (American Petroleum Institute) separators</b> can be used for better efficient oil separation. Here specific gravity difference between oil and wastewater is the main principle behind the separation. Oil is collected form the surface. Sediment that is settled down at the bottom of the tank is directed to the central sludge management facilities. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                           Then wastewater is transferred to <b>flow equalization tank</b>. As the production cycle of industries varies, water is stored for certain period of time in the flow equalization tank. It produces stable wastewater for downstream process. Temperature of the wastewater is reduced by giving enough retention</span> <span style="font-size: 14.0pt; line-height: 115%;">time in this tank. The variation of the concentration of wastewater throughout the whole tank is avoided by continuous mixing. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                           Coagulant agents such as lime, alum, ferrous Sulfate and ferric Sulfate are added to remove the dissolved solid matter. After addition of coagulant agent, water is rapidy mixed to disperse the coagulant throughout all of the water in the <b>coagulation tank</b>. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                           Then water is transferred into <b>flocculation tank</b>. Here water is gently mixed to allow</span> <span style="font-size: 14.0pt; line-height: 115%;">flocs to form. These flocs are removed by using a <b>sedimentation tank</b>. Chemical flocs are settled down under gravity. They are collected from the bottom of the tank and send for central sludge management facilities.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                           Wastewater is passed into a <b>floatation tank</b> to remove solid particle from the water. It helps to remove very tiny light particles from the water. Here a gas (air bubbles) is introduced and to form scum which is collected from the surface. The sediments that are collected at the bottom are directed to the central sludge management facilities.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                           The biodegradable organic matter in the wastewater is removed by using <b>aeration tank</b>. Here aerobic respiratory microorganisms are employed under aeration. They oxidize organic matter completely into carbon dioxide and water without leaving any residues. External nutrient sources such as canteen waste or cow dung can be added to enhance the efficiency of the microorganisms. Aerobic respiratory microorganisms are also added externally to maintain high <b>F/M (Food to Microorganisms) ratio</b> because when microorganisms are higher than the available food, they tend to form flocs via attaching to each other.  These biological flogs are removed by using another settling tank. Retention time of wastewater is 4-8 hours in the aeration tank. The amount of sediments can be reduced by extending the retention time from 1-2 days.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                           Then wastewater is transferred to secondary clarifier or settling tank. Here biological flocs are settled down under gravity. They are collected from bottom. A portion of sediment is returned back to the aeration tank to as <b>activated sludge </b>to enhance the treatment of incoming wastewater. Remaining portion is disposed as sludge. It can be degraded completely in an anaerobic digester. Unoxidized sludge mostly includes high strength organics such as lignin and cellulose which is unable to degrade by aerobic respiratory bacteria.  Anaerobic digestion of organic matter produces methane which combustible gas which can be used as the alternative fuel for fossil fuel. This sludge also can be send to central sludge treatment facilities to treat with the sludge which is generated by other process.  <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                           After biological treatment of wastewater, it is transferred to another tank for <b>disinfection</b>. Disinfection is used to kill disease cause microorganisms. Chlorine treatment, ozonation and UV treatments are the available method for disinfection. Although use of chlorine is cost effective, excess amount of chlorine produce disinfection by products (DBP) which are carcinogen chemicals. Both UV and ozonation do not leave any chemical residue. But ozonation require highly specialized equipment to produce ozone and contact with water. So UV treatment is relatively cost effective and environmental safe. <o:p></o:p></span></div> <span style="font-family: "calibri" , "sans-serif"; font-size: 14.0pt; line-height: 115%;"> </span><br /> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                           These levels of treatment is not enough to release wastewater into public sewers or receiving water bodies because wastewater still contains non degraded organic matter and excess nutrient such as phosphate and nitrate. They can be removed by using different chemical, physical and biological methods. But it has to be combined several method to achieve better tertiary treatment. It is expensive and labor intensive. Therefore <b>construction of artificial wetland </b>solves these problems and gives relatively efficient and environmentally friendly tertiary treatment.</span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhS7tw-3827Q7gC89rU9lHP4AuALAy3iohz_lEHrQw7-gbzVUYvmluT67vf7ojHGDe8HYEzpzRw8W1tg7N4aVJLHExE0akG8r5mD0FJgl3SUwVITGfvKnJWGsY6DIgPGCMv8XkNJN86WXID/s1600/img5.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhS7tw-3827Q7gC89rU9lHP4AuALAy3iohz_lEHrQw7-gbzVUYvmluT67vf7ojHGDe8HYEzpzRw8W1tg7N4aVJLHExE0akG8r5mD0FJgl3SUwVITGfvKnJWGsY6DIgPGCMv8XkNJN86WXID/s640/img5.jpg" width="640" /></a></div> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">Wetland system consists mainly there components such as surface substrate,</span> <span style="font-size: 14.0pt; line-height: 115%;">macrophytes and microbial communities. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                          A gavel layer is applied as the top layer of surface substrate. Beneath the gavel layer a coarse media is applied.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                          Rooted emergent macrophytes such as cattle tails are planted in the coarse media. They produce aerial stem with underground extensive fibrous root system.  These the macrophytes support the growth of microbial communities via association with their root systems and remove certain pollutants from the water. The plants uptake the excess nutrient which is able accelerates their growth from the wastewater. Some plants are capable of absorbing toxic metal of the water such as <b><i>Ipomoea aquatic</i></b>.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                        The microorganisms help to further removal of organics. They plays important role for the removal of excess nutrients. Ammonium ions are removed from the wastewater by denitrification. Oxygen leaks from the rhizomes into the nearby waster where the aerated zone is located. In aerated zones, ammonium ions are oxidized into nitrite by <b><i>Nitrosomonas</i></b> then nitrite is further oxidized intro nitrate by <b><i>Nitrobactor.  </i></b>Then these nitrates are reduced into nitrogen gas which expels from water into the atmosphere by <b><i>Thiobacillus dentrificans </i></b>in the anaerobic zone.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><span style="font-size: 14pt;">                           </span><span style="font-size: 14pt;">In addition above biological process, wetland use physical and chemical methods to remove the pollutants from the wastewater. Main physical processes are sedimentation and filtration. Above gavel and coarse media of the wetland traps the remaining sediment in the incoming wastewater through straining. Volatile organic compounds (VOC) such as phenolic compounds which are resistant to remove during primary and secondary treatment are subjected to volatilization. Those VOCs diffuses from the wastewater from atmosphere due to the action of the photo energy. Chemical process includes the sorption, redox reactions, chemical precipitation and hydrolysis.</span> <o:p></o:p></span></div>

Construction of Artificial Wetland for Wastewater Treatment

                  Wastewater that are produced by industries are needed to treat in a proper manner before discharge into public sewer or r...

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Microbiological Analysis of Potable Drinking Water

<div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgwh-9Dv2ExYRITS5L41ZCtvovZ-cA4BGpDkF8MjosSFj3EG4jIMWOkN3h7oHloQgkJ6UwCXI2jMEevpG7p_HYAxHr-m9fDBXG9QhP19dcAmTyAMwvD3uYAA-pv4t52gtOYI11p7z-5y0y6/s1600/img1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="384" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgwh-9Dv2ExYRITS5L41ZCtvovZ-cA4BGpDkF8MjosSFj3EG4jIMWOkN3h7oHloQgkJ6UwCXI2jMEevpG7p_HYAxHr-m9fDBXG9QhP19dcAmTyAMwvD3uYAA-pv4t52gtOYI11p7z-5y0y6/s640/img1.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%;">Drinking water sources can be accidently contaminated by human fecal pollution. But release of small quantity of fecal matter does not cause serious health problems because it is highly diluted within the natural water bodies. If water bodies are once fecal polluted, it contains pathogens of fecal origins.  This pathogen may include protozoan cysts, nematodes larvae, nematode eggs, viruses, bacteria and fungi. But it is difficult to test for each and every above organism so test for indicator organisms such as tests for <i>E coli</i> is done. It is an intestinal microorganism that lives in human and most animal bodies. <i>E coli</i> releases through the fecal matter into aquatic water bodies. They do not die as soon as they release from the human body. But they cannot survive for many days in the water due to low nutrient availability. It is assumed that fecal origin pathogens also have similar duration of survival within aquatic water bodies.</span> <span style="font-size: 14.0pt; line-height: 115%;">According to WHO, drinking water cannot contain at least one E coli. If drinking water contain at least one E coli, it is not suitable for human consumption.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                      Testing for E <i>coli</i> is cost effective and time saving. If <i>E coli</i> are present, it indicated that there is high probability of presence of fecal origin pathogens. But even if direct testing for <i>E coli</i> is cost because electricity has to be applied to inoculate the microorganisms in the water sample at high temperatures  in order to test for <i>E coli</i>. So initially testing for coliform is done. Coliform is a group of bacteria that are capable of fermentation lactose and producing acids and gas. Coliforms are gram negative and rod shaped bacteria. <i>E coli</i> are also one of the members of coliform. If the result of coliform test is negative, there is no need of further testing. Therefore water can be released for human consumption. <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                Testing for <i>E coli</i> is done in three steps such as presumptive test, coliform test and conform test. In presumptive test, MaConkey broth is used the culture media. MaConkey broth media acts as the selective and differentiate medium for isolation of gram negative lactose fermentative bacteria.  It is comprised of lactose as the carbon source, peptone as the nitrogen and other nutrient source, bile salt, pH indicator and NaCl. Bile broth is added to suppress the growth of gram positive bacteria. Bromo cresol purple or neutral red is added as the pH indicator to observe to acid production of bacteria. If Bromo cresol purple is added, it changes its color as yellow due to the acid production. If neutral red is added as the pH indicator, it changes it color as dark red due to the acid production. NaCl is added to t maintain the osmotic balance of the medium. <o:p></o:p></span></div> <br /> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;">                  Here five test tubes are prepared with 9 mL of double strength MaConkey broth and 1ml of water sample to prepare 10</span><span style="font-size: 24.0pt; line-height: 115%;">◦ </span><span style="font-size: 14.0pt; line-height: 115%;">series.</span><span style="font-size: 24.0pt; line-height: 115%;"> </span><span style="font-size: 14.0pt; line-height: 115%;">Then another five test tubes are prepared with 9mL of single strength MaConkey broth and 1ml of water sample to prepare 10^-1 series. 1mL of water sample is taken into another test tube containing 9mL of peptone to dilute water to 10^-1. Then from that test tube 1mL is added to five test tubes filled with 9mL of single strength MaConkey broth to prepare 10^-2 series. These test tube series are inoculated at 37◦C for 24-48 hours. Color change due to the acid production and gas collected in the Durham tube are taken as the positive result of this test.</span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjLbeM1ayOJ50HsMffdn9DOSCd9qQtGOgcQB0-UJ3RuobVQd80AiO6JryKc6qxNoAglzRNWM_Xwou86m3gHakGFIhevXtk_U8FXY84BKlxr9tHOuu-5U3-CbH_9qaDZdDsp5Ag5IVwxB1Dt/s1600/img2.PNG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="275" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjLbeM1ayOJ50HsMffdn9DOSCd9qQtGOgcQB0-UJ3RuobVQd80AiO6JryKc6qxNoAglzRNWM_Xwou86m3gHakGFIhevXtk_U8FXY84BKlxr9tHOuu-5U3-CbH_9qaDZdDsp5Ag5IVwxB1Dt/s400/img2.PNG" width="400" /></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%;">If the result of presumptive test is negative, there is no need of further testing.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"> It indicated that there is no coliform that means there are no E coli. If results are positive, it indicates the presence of coliform. So further testing is needed to confirm whether presence or absence of coli.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><span style="font-size: 14pt;">                       </span><span style="font-size: 14pt;">The test tubes those shows positive results are used to inoculate in the conform test. Two methods are available such as BGLB broth or EMBA. BGLB broth means brilliant green lactose bile broth. Here lactose also is added as carbon source for bacterial fermentation. Brilliant green dye suppress the growth some selective gram negative bacteria. Bile suppresses the growth of gram positive bacteria. One set of BGLB broth containing test tube are inoculated at 37◦ C for total coliform. Total coliform contain both environmental coliform and fecal coliform. Another set of BGLB broth containing test tube are inoculated at 44◦ C for fecal coliform. Gas production in the Durham tube is taken as the positive results in this test.</span></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEixIQE4k4bkvZ9R_zPGm88b7ziYu3qEfnsarMlYuYqooHd-kXsHgXS0BtoXgcfPCg4AZq6H2yOgmjL7yfnv6XAxVj_W8r3vhlE6DsVVktNRqLb1NooOR3eAat67FoSBAjF8Y-kBQGjfKHD0/s1600/img3.PNG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="200" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEixIQE4k4bkvZ9R_zPGm88b7ziYu3qEfnsarMlYuYqooHd-kXsHgXS0BtoXgcfPCg4AZq6H2yOgmjL7yfnv6XAxVj_W8r3vhlE6DsVVktNRqLb1NooOR3eAat67FoSBAjF8Y-kBQGjfKHD0/s400/img3.PNG" width="400" /></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%;"><span style="font-family: Calibri, sans-serif; font-size: 14pt; line-height: 115%;">Plate containing EMBA agar is used to conform the presence of <i>E coli</i>. Inoculum from the test tubes that shows positive results are taken into plates for inoculate at 37◦C for 24-48 hours. EMBA means Eosin Methylene Blue Agar.</span><span style="font-family: Calibri, sans-serif; font-size: 11pt; line-height: 115%;"> </span><span style="font-family: Calibri, sans-serif; font-size: 14pt; line-height: 115%;">Eosin Methylene Blue dyes suppresses the growth of gram positive bacteria. Agar is added as the solidifying agent. Lactose is added as the carbon source for bacterial fermentation. It gives characteristic green color with metallic sheen if strong acid producers are present such as <i>E coli</i>. It gives pink colored colonies if weak acid producers are present such as <i>Enterobacto</i>r. Non lactose fermentative does not give any color.</span></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiGJp6mWZ3xiZ6w9tgtLEo8dWaXtD3SjuMTrLuO-mP_felBVQP_5ld7YmsbyKxsXSTTIaI5e8mvwi7vbc_dn7Sn4sVVIAg3XKbnGBPcFSKh7jQnsOs3JTFhNIWh9Vqny2WGOYU4aEonBXHf/s1600/img4.PNG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="228" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiGJp6mWZ3xiZ6w9tgtLEo8dWaXtD3SjuMTrLuO-mP_felBVQP_5ld7YmsbyKxsXSTTIaI5e8mvwi7vbc_dn7Sn4sVVIAg3XKbnGBPcFSKh7jQnsOs3JTFhNIWh9Vqny2WGOYU4aEonBXHf/s400/img4.PNG" width="400" /></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%;"><br /></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"> If results from conform test is negative, there is no fecal coliform. So water can be released for human consumption. But if results are positive, further testing is needed because In addition to <i>E coli, Enterobacto</i>r also shows positive results for confirm test.<o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><span style="font-size: 14pt;">                          </span><span style="font-size: 14pt;">Then complete test is done to confirm exactly presence of </span><i style="font-size: 14pt;">E coli</i><span style="font-size: 14pt;">. IMViC tests are done. IMViC means Indol Methylene red VP Citrate tests. </span><i style="font-size: 14pt;">E coli</i><span style="font-size: 14pt;"> give positive results for Indol and Methylene test. In Indol test, only E coli is able to digeste tryptone because only </span><i style="font-size: 14pt;">E coli </i><span style="font-size: 14pt;">tryptonase enzyme to form Indol ring. As Indol ring cannot be observed due to the colorless, knovas reagent is added. If Indol ring is present, it appears in red in color. </span><i style="font-size: 14pt;">Enterobactor</i><span style="font-size: 14pt;"> gives positive results for VP and Citrate tests. If the results of complete test are also positive, it indicated that presence of </span><i style="font-size: 14pt;">E coli</i><span style="font-size: 14pt;">. So water cannot be released for human consumption due to the possibility of presence of fecal origin pathogens.</span> <o:p></o:p></span></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj1zOk5Y3EkIstm16EQdDF6G8NqyfhT0NCKfD_h97y-kN6xEIIw4wyB0x-jmZ5DC8YYd8HXZ5uSGsHZmMrUPIylIc2HEELb-8kUoPKmzByLeGuhGZ8tWe_2JfTh_ko_P1Z4XxdI3rhdxeAr/s1600/img.PNG.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="232" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj1zOk5Y3EkIstm16EQdDF6G8NqyfhT0NCKfD_h97y-kN6xEIIw4wyB0x-jmZ5DC8YYd8HXZ5uSGsHZmMrUPIylIc2HEELb-8kUoPKmzByLeGuhGZ8tWe_2JfTh_ko_P1Z4XxdI3rhdxeAr/s400/img.PNG.jpg" width="400" /></a></div> <div class="MsoNormal"> <span style="font-size: 14.0pt; line-height: 115%;"><br /></span></div>

Microbiological Analysis of Potable Drinking Water

Drinking water sources can be accidently contaminated by human fecal pollution. But release of small quantity of fecal matter does not ...

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