International Letters of Natural Sciences Vol. 9

Abstract: The objective of the study described the importance of biogas and its importance. The biogas generally obtained from the waste. The so-called wastes that we discard and suffer with the consequences of improper management are of course partly huge energy and fertilizer sources that can support energy demands of cities greatly. Urban waste disposal is a serious challenge in all cities in the developing world, and its accumulation is an additional health hazard. Reliable and generally accepted disposal of the comparatively large amounts of digestate produced is necessary if biogas production is to be implemented. In this regard's discussion has been about the biogas production reaction involves, design and applications

Abstract: A venturi scrubber is designed to effectively use the energy from the inlet gas stream to atomize the liquid being used to scrub the gas stream. This type of technology is a part of the group of air pollution controls. The air pollution generated from the industry is now become serious problem for the environment, which affect the living and non living thing on the Earth. Among all the air pollution monitoring equipment venturi scrubber found to suitable for prevention of air pollution by pesticide. It was found that scrubber shows 99.1 % efficiency.

Abstract: Wastewater treatment is becoming ever more critical due to diminishing water resources, increasing wastewater disposal costs, and stricter discharge regulations that have lowered permissible contaminant levels in waste streams. The ultimate goal of wastewater management is the protection of the environment in a manner commensurate with public health and socio-economic concerns. The aim of our study is to use natural occurring polymeric coagulant to reduce the chemical oxygen demand and color from the industrial waste water. It was found that 83% of Chemical oxygen demand and 90% of color reduction was observed with chitosan.

Abstract: As far as the detection of metal genotoxicity in fish is concerned, micronucleus (MN) test is considered an extremely suitable measure. In this study, frequencies of micronucleated erythrocytes were scored in peripheral blood of catfish, Heteropneustes fossilis (bloch) after acute in-vivo exposure of zinc at different concentrations (5, 10 and 30 ppm) in the laboratory condition. These three concentrations of zinc were tested at different durations such as 24h, 48h, 72h and 96h respectively. Highly significant (P < 0.001) increased values were obtained for MN frequencies in the peripheral erythrocytes of exposed fishes compared to control groups of fishes. These results confirm that dose- and time-dependent micronucleation in the peripheral erythrocytes of fish after short-term exposure to zinc could provide valuable information regarding zinc containing effluent quality and also help in genetic biomonitoring with this test model. In this context safe concentration of zinc vis-a-vis genotoxicity range could be evaluated for future studies.

Abstract: The aim of the present research was to estimate erosion and sediment and to formulate a map of the basin's erosion intensity using the satellite data, GIS technique and to compare the hydrometric stations' statistics. Using the Land sat satellite images among the results obtained from these data through (TM, ETM+), coverage index (NDVI) as well as a combination of bands 2, 3 and 4 for determining the type of land use and for assessing the soil texture in terms of regional aerial images tone and in accordance with the physiographic of the basin through sampling the soil texture , the map of the basin's texture was obtained. Assessing the surface and river erosion was also conducted using the aerial images and field visits. Given the data obtained and the model being applied, the special sediment rate in the basin was 5/19 tons per hectare, while the overall sediment rate obtained for the entire basin was estimated 5496533 tons in a year. Meantime, the observed and estimated value in the hydrometric station of Nesare Olya for as much as 553230 tons in a year shows a less than 1 % difference in the entire estimation of the sediments accumulated in the back of the dam while its sediment load rate estimation as much as 5/16 tons per hectare shows a 0/03 difference rate for the station.

Abstract: The recent experiment was conducted to assess the effect of herbicide (quizalafop-p-ethyl) on growth, photosynthetic pigments, enzymes and yield of Black gram (Vigna mungo L.) during the summer season 2013-2014. This experiment comprised black gram (variety ADT 3) and different concentrations of herbicide (quizalafop-p-ethyl) treatments compared with control. Reduction in growth, photosynthetic pigments, enzymes and yield parameters were observed with 0.5 % herbicide application followed by 1 %, 1.5 % and 2 %, out of all treatments 0.5 % shows least reduction. Thus, 0.5 % herbicide application is the safest way for weed control in Black gram field as it showed least adverse effect on growth, photosynthetic pigments, enzymes and yield of crop when compared with other treatments.

Abstract: Chromium is one of the most common toxic metals present in the environment that induces various toxic effects in plants. A pot experiment was conducted to determine the effects of chromium on germination percentage, seedling growth, chlorophyll ‘a’, ‘b’ and proline content of Sesbania sesban (L.) Merr. The seedlings were treated with different concentrations of control, 0.10, 0.25, 0.50, 0.75 and 1.00 g kg-1 of chromium. The parameters such as germination percentage, root and shoot length, seedling fresh weight dry weight, chlorophyll ‘a’, ‘b’ and proline content of leaves were measured. Our results indicated that a significant inhibitory effect was observed at all levels of chromium compared to control. Increasing the concentration of chromium to 1.00 g kg-1 showed a significant decrease in seed germination, shoot and root length, fresh weight, dry weight and chlorophyll ‘a’ and ‘b’ content of plant. While proline, catalase and peroxidase contents were increased by increasing Cr concentration. It was also noted that accumulation of chromium in the roots was much higher than the shoots of the seedlings under treatment.

Abstract: The present study deals to know morphological damages of leaves of four selected plant species near roadside due to vehicular air pollution in Kolkata, India. The selected plant species are Ficus bengalensis, Ficus religiosa, Alstonia scholaris and Neolamarckia cadamba as these are very common as avenue trees. The study area was selected as per Low vehicular load (LVL) as control area, moderate vehicular load (MVL) area, high vehicular load (HVL) area and heavy vehicular load (HeVL) These three sampling stations were selected on the basis of moderate, high and heavy traffic density and continuous vehicular movement as per visualization. The control area was considered as time dependent vehicular movement due to less traffic density. The morphological damages with special reference to length (L), breadth (B) and L/B ratio and visible injuries in leaves. The visible injuries such as pigmentation, chlorosis, necrosis and burning of leaves of four selected species is documented. There was an increasing and decreasing tends in all four plant species at all three vehicular emission exposed sites (MVL, HVL and HeVL) compared to control site (LVL). In all experimental sites such as MVL, HVL and HeVL, the extra growth and reduction pattern significantly (P < 0.001, 0.01 or 0.05) observed when compared to control site (LVL) for L, B and L/B ratio. The visible injuries (in %) of leaves were also observed in increasing trends. This study is a preliminary assessment of tolerant species that already have been used in greenbelt development to protect air pollutants as well as biological monitoring to know exact load of automobile air pollution but further researches are needed in relation to biochemical and genetic damage study. It was observed that out of four selected species Ficus bengalensis, Alstonia scholaris and Neolamarckia cadamba are more tolerant species and Ficus religiosa is a less tolerant species because of these may have fighting abilities by waxy coatings, accumulation and degradation abilities to vehicular air pollution at all exposed area when compared to control area.