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761.
In an effort to determine vehicular impact on soil quality, soil samples were collected from three different zones (Pahalgam, Batakote, and Chandanwari) in Pahalgam forest ecosystem. Results showed that a significant decrease in moisture content, organic carbon, available nitrogen, and potassium was observed in nearby road side soils. However, pH was observed to be on neutral side and available phosphorus recorded high concentration. The concentration of heavy metals Pb2+, Cu2+, Zn2+, Ni2+, and Cd2+ estimated was also significantly high. Furthermore, concentration of Pb2+ at high vehicular load subzones was observed to be highest (1.168 mg/Kg) followed by Zn2+ (0.896 mg/Kg), Ni2+ (0.649 mg/Kg), Cu2+ (0.415 mg/Kg), and Cd2+ (0.079 mg/Kg). An inter-zone analysis revealed that the concentration of the heavy metals (Pb2+?>?Ni2+?>?Cd2+) was observed to follow the trend, Z-I?>?Z-II?>?Z-III. Variation along the temporal gradient and the impact on soil qualities were notably higher in summer. Vehicular pollution to a great extent impacts physico-chemical characteristics and more interestingly adds substantial concentration of heavy metals in soils.  相似文献   
762.
Rising global population would force farmers to amplify food production substantially in upcoming 3–4 decades. The easiest way to increase grain production is through expanding cropping area by clearing uncultivated land. This is attained by permitting deadly loss of carbon (C) stocks, jeopardizing ecosystem biodiversity and deteriorating environmental quality. We aim to propose key agronomical tactics, livestock management strategy and advance approaches for aquaculture to increase productivity and simultaneously reduce the environmental impacts of farming sector. For this, we considered three major sectors of farming, i.e. agriculture, fishery and dairy. We collected literatures stating approaches or technologies that could reduce GHG emission from these sectors. Thereafter, we synthesized strategies or options that are more feasible and accessible for inclusion in farm sector to reduce GHG emission. Having comprehensively reviewed several publications, we propose potential strategies to reduce GHG emission. Agronomic practices like crop diversification, reducing summer fallow, soil organic carbon sequestration, tillage and crop residue management and inclusion of N2-fixing pulses in crop rotations are some of those. Livestock management through changing animals’ diets, optimal use of the gas produced from manures, frequent and complete manure removal from animal housing and aquaculture management strategies to improve fish health and improve feed conversion efficiency could reduce their GHG emission footprint too. Adapting of effective and economic practices GHG emission footprint reduction potential of farming sector could make farming sector a C neutral enterprise. To overcome the ecological, technological and institutional barriers, policy on trade, tax, grazing practice and GHG pricing should be implemented properly.  相似文献   
763.
Journal of Material Cycles and Waste Management - Global waste production is pegging at unforeseen heights and alarming for its sustainable management. Information and Communication Technologies...  相似文献   
764.
Environmental Science and Pollution Research - The control of storage insect pests is largely based on synthetic pesticides. However, due to fast growing resistance in the targeted insects,...  相似文献   
765.
Environment, Development and Sustainability - Recorded seasonal variation and uneven distribution of rainfall is one of the major issues to the agrarian society and the domestic water users today....  相似文献   
766.
Due to inherent advantages, waste polyethylene (generated from domestic sources) has been used as asphalt modifier. This article discusses viscoelastic properties of the polyethylene modified asphalt binder. Several asphalt concrete mixtures were designed by varying polyethylene and asphalt content. Shredded polyethylene incorporated into asphalt concrete by dry mixing process. Using optimised asphalt content (at several polyethylene percentages), mixtures were prepared and compacted. These compacted specimens were aged for different duration in convection oven. Asphalt binder (from aged specimens) was extracted and tested for its viscoelastic properties using dynamic shear rheometer. Comparison of mastercurves indicated increase in complex modulus and decrease in phase angle values with addition of polyethylene at all reduced frequencies. However, the extent of change was highly dependent on frequency, aging duration and polyethylene content. This indicates that the addition of polyethylene provides more resilience to asphalt binder especially with less aging time. Storage modulus mastercurves (at lower frequencies) and relaxation modulus values (at longer time) indicate polyethylene provides additional stiffening to binder. Further, changes in viscous modulus with addition of polyethylene were marginal. Overall results indicate that waste polyethylene improves the properties of asphalt binder over extended loading period when heated for less time during mixing.  相似文献   
767.
Environmental Chemistry Letters - Aflatoxin M1 contamination in milk and dairy products is a major issue worldwide. Aflatoxin is a carcinogen that enters into the milk through animals feed. Here,...  相似文献   
768.
The air pollution due to anthropogenic activities seriously affected human life, vegetation, and heritage as well. The vegetation cover in and around the city mitigates the air pollution by acting as a sink for pollution. An attempt was made to evaluate biochemical changes occurred in four selected plant species, namely Azadirachta indica, Mangifera indica, Delonix regia, and Cassia fistula of residential, commercial, and industrial areas of Nagpur city in India. It was observed that the correlated values of air pollutants and plant leaves characteristics alter foliar biochemical features (i.e., chlorophyll and ascorbic acid content, pH and relative water content) of plants due to air pollution. The changes in air pollution tolerance index of plants was also estimated which revealed that these plants can be used as a biomarker of air pollution.  相似文献   
769.
The groundwater samples collected from the shallow and deep groundwater aquifers of an industrial area of the Kanpur city (Uttar Pradesh, India) were analyzed for the concentration levels and distribution pattern of nitrogenous species, such as nitrate-nitrogen (NO3-N), nitrite-nitrogen (NO2-N), ammonical-nitrogen (NH4-N), organic-nitrogen (Org-N) and total Kjeldahl-nitrogen (TKN) to identify the possible contamination source. Geo-statistical approach was adopted to determine the distribution and extent of the contaminant plume. In the groundwater aquifers NO3-N, NO2-N, NH4-N, TKN, Org-N and Total-N ranged from 0.10 to 64.10, BDL (below detection limit)-6.57, BDL-39.00, 7.84–202.16, 1.39–198.97 and 8.89–219.43 mg l−1, respectively. About 42% and 26% of the groundwater samples of the shallow and deep groundwater aquifers, respectively, exceeded the BIS (Bureau of Indian Standards) guideline value of 10 mg l−1 for NO3-N and may pose serious health hazards to the people of the area. The results of the study revealed that the groundwater aquifers of the study area are highly contaminated with the nitrate and indicates point source pollution of nitrate in the study area.  相似文献   
770.
Breast milk is the natural and optimal food for the infants. In addition to meeting the nutritional needs, breast milk provides numerous immunological, developmental, psychological, ecological and practical advantages. The levels of the DDT and HCH residues in human milk collected from remote rural part of Agra were analysed. Beta and gamma isomers of HCH accounts for the major residue of total HCH excreted in breast milk. Delta-HCH was not detected in the samples. 95% of the samples were found to be contaminated with DDT and its metabolites. DDD was found in 88% of the samples analyzed. The total concentration of DDT and HCH were found lower than the previous studies carried out in India. The study shows the decreasing levels of these organochlorine pesticides from the environment. Total concentration of total DDT is higher than total HCH.  相似文献   
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