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1.
This study aims in linking the biophysical and socioeconomic data base layers with the technical coefficients or simulation models for agri-production estimates and land use planning under normal and extreme climatic events, and exploring the resource and inputs management options in village Shikohpur, Gurgaon district located in the northwest part of India. The socioeconomic profile of Shikohpur is highly skewed with mostly small and marginal farmers. Though the areas under wheat in Shikohpur are increasing, the productivity is declining or remaining stagnant over the years. Most of the area during kharif season (June-September) remains fallow. Pearl millet based cropping systems (pearl millet-mustard and pearl millet-wheat) are predominant. Soils are mostly loamy sand to sandy loam with average of 70-80% sand content. Organic C content in soil is less than 0.3%, due to high prevailing temperature with little rainfall and also intensive agriculture followed in this region. Though the annual average seasonal rainfall in Gurgaon did not have much variation over the years, occurrence of extreme climate events has increased in the last two decades. The crop intensity is low and the water table is declining. Water and nitrogen production functions were developed for the important crops of the region, for their subsequent use in scheduling of the inputs. InfoCrop, WTGROWS and technical coefficients were used for crop planning and resource management under climate change and its variability, extreme events, limited resource availability and crop intensification. These will help in disseminating necessary agro-advisories to the farmers so that they will be able to manipulate the inputs and agronomic management practices for sustained agricultural production under normal as well as extreme climatic conditions.  相似文献   
2.
Field experiments were carried out during 1996–97at Gulawathi, Muthiani and Salarpur Villages, IARI Farm, NewDelhi and NCPP Campus, Dadri to evaluate changes in soilcharacteristics and growth of wheat (Triticum aestivum L.),mustard (Brassica juncea L.), lentil (Lence esculentaMoench.), rice (Oryza sativa L.) and maize (Zea mays L.) byvarying amounts of flyash addition (up to 50t ha-1) in soils atsowing/transplanting time of crops. Flyash addition in areasadjoining NCPP Thermal Power Plant, Dadri, Ghaziabad, U.P.ranged from 5–12 t ha-1 yr-1 in 1995–96. Shoot and root growthand yield of test crops at different locations after flyashincorporation resulted in beneficial effects of flyashaddition in most cases. The silt dominant texture of flyashimproved loamy sand to sandy loam textures of the surfacesoils at the farmers' fields. The increased growth in yield ofcrops with flyash incorporation was possibly due tomodifications in soil moisture retention and transmissioncharacteristics, bulk density, physico-chemical characterssuch as pH and EC and organic carbon content. The response offlyash addition in the soil on soil health and cropproductivity needs to be evaluated on long-term sustainableaspects.  相似文献   
3.
Four efficient Cr(VI)-reducing bacterial strains were isolated from rhizospheric soil of plants irrigated with tannery effluent and investigated for in vitro Cr(VI) reduction. Based on 16S rRNA gene sequencing, the isolated strains SUCR44, SUCR140, SUCR186, and SUCR188 were identified as Bacillus sp. (JN674188), Microbacterium sp. (JN674183), Bacillus thuringiensis (JN674184), and Bacillus subtilis (JN674195), respectively. All four isolates could completely reduce Cr(VI) in culture media at 0.2 mM concentration within a period of 24–120 h; SUCR140 completely reduced Cr(VI) within 24 h. Assay with the permeabilized cells (treated with Triton X-100 and Tween 80) and cell-free assay demonstrated that the Cr(VI) reduction activity was mainly associated with the soluble fraction of cells. Considering the major amount of chromium being reduced within 24–48 h, these fractions could have been released extracellularly also during their growth. At the temperature optima of 28 °C and pH?7.0, the specific activity of Cr(VI) reduction was determined to be 0.32, 0.42, 0.34, and 0.28 μmol Cr(VI)?min?1?mg?1 protein for isolates SUCR44, SUCR140, SUCR186, and SUCR188, respectively. Addition of 0.1 mM NADH enhanced the Cr(VI) reduction in the cell-free extracts of all four strains. The Cr(VI) reduction activity in cell-free extracts of all the isolates was stable in presence of different metal ions tested except Hg2+. Beside this, urea and thiourea also reduced the activity of chromate reduction to significant levels.  相似文献   
4.
Pot culture experiments were conducted in a glasshouse to evaluate the effects of four efficient Cr(VI)-reducing bacterial strains (SUCR44, SUCR140, SUCR186, and SUCR188) isolated from rhizospheric soil, and four arbuscular mycorrhizal fungi (AMF—Glomus mosseae, G. aggregatum, G. fasciculatum, and G. intraradices) alone or in combination, on Zea mays in artificially Cr(VI)-amended soil. Presence of a strain of Microbacterium sp. SUCR140 reduced the chromate toxicity resulting in improved growth and yields of plants compared to control. The bioavailability of Cr(VI) in soil and its uptake by the plant reduced significantly in SUCR140-treated plants; the effects of AMF, however, either alone or in presence of SUCR140 were not significant. On the other hand, presence of AMF significantly restricted the transport of chromium from root to the aerial parts of plants. The populations of AMF chlamydospores in soil and its root colonization improved in presence of SUCR140. This study demonstrates the usefulness of an efficient Cr(VI)-reducing bacterial strain SUCR140 in improving yields probably through reducing toxicity to plants by lowering bioavailability and uptake of Cr(VI) and improving nutrient availability through increased mycorrhizal colonization which also restricted the transport of chromium to the aerial parts.  相似文献   
5.
Human milk samples collected from areas having intensive cotton cultivation and sparse cotton cultivation in Punjab (India) were analysed for organochlorine insecticides. Both DDT and HCH were detected in almost all the samples analysed. The average levels of Sigma-DDT and Sigma-HCH residues in samples from cotton-growing areas were significantly higher than in those from areas where cotton is sparsely grown. Residues of Sigma-DDT mainly comprised p,p'-DDT and p,p'-DDE, while those of Sigma-HCH residues were mainly in the form of its beta-isomer. Median values of 0.52 microg g(-1) of Sigma-DDT and 0.19 microg g(-1) of Sigma-HCH in samples of human milk from cotton-growing areas of Punjab (India) were higher than those reported from most other countries in the World.  相似文献   
6.
In water stressed regions, water managers are exploring new horizons that would help in long‐range streamflow forecasts. Oceanic‐atmospheric oscillations have been shown to influence streamflow variability. In this study, long‐lead time streamflow forecasts are made using a multiclass kernel‐based data‐driven support vector machine (SVM) model. The extended streamflow records based on tree ring reconstructions were used to provide a longer time series data. Reconstructed data were used from 1658 to 1952 and the instrumental record was used from 1953 to 2007. Reconstructions for oceanic‐atmospheric oscillations included the El Niño‐Southern Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, and North Atlantic Oscillation. Streamflow forecasts using all four oscillations were made with one‐year to five‐year lead times for 21 gages in the western United States. This is the first study that uses both instrumental and reconstructed data of oscillations in SVM model to improve streamflow forecast lead time. SVM model was able to provide “satisfactory” to “very good” forecasts with one‐ to five‐year lead time for the selected gages. The use of all the oscillation indices helped in achieving better predictability compared to using individual oscillations. The SVM modeling results are better when compared with multiple linear regression model forecasts. The findings are statistical in nature and are expected to be useful for long‐term water resources planning and management.  相似文献   
7.
The current study improves streamflow forecast lead‐time by coupling climate information in a data‐driven modeling framework. The spatial–temporal correlation between streamflow and oceanic–atmospheric variability represented by sea surface temperature (SST), 500‐mbar geopotential height (Z500), 500‐mbar specific humidity (SH500), and 500‐mbar east–west wind (U500) of the Pacific and the Atlantic Ocean is obtained through singular value decomposition (SVD). SVD significant regions are weighted using a nonparametric method and utilized as input in a support vector machine (SVM) framework. The Upper Rio Grande River Basin (URGRB) is selected to test the applicability of the proposed model for the period of 1965–2014. The April–August streamflow volume is forecasted using previous year climate variability, creating a lagged relationship of 1–13 months. SVD results showed the streamflow variability was better explained by SST and U500 as compared to Z500 and SH500. The SVM model showed satisfactory forecasting ability with best results achieved using a one‐month lead to forecast the following four‐month period. Overall, the SVM results showed excellent predictive ability with average correlation coefficient of 0.89 and Nash–Sutcliffe efficiency of 0.79. This study contributes toward identifying new SVD significant regions and improving streamflow forecast lead‐time of the URGRB.  相似文献   
8.
Environmental Science and Pollution Research - Traumatic brain injury (TBI) is a neurological disorder which represents a major health issue worldwide. It causes mortality and disability among all...  相似文献   
9.
Energy is a vital and growing need for human activities such as transport, agriculture and industry. The transport and agriculture sectors are major consumers of fossil fuel. However, availability of fossil fuels is limited. The use of fossil fuels is of increasing environmental concerns because it produces toxic airborne particulates and greenhouse gases such as CO2. The increasing industrialization and motorization of the world led to a steep rise for the demand of petroleum-based fuels. Hence, it is necessary to seek alternative fuels, which can be produced from resources available locally within the country such as alcohol, biodiesel and vegetable oils. Biodiesel is defined as the mono alkyl esters of vegetable oils or animal fats. Biodiesel is the best candidate for diesel fuels in the diesel engines. The advantage of biodiesel over gasoline and petroleum/diesel is its eco-friendly nature. This article reviews the production, characterization and current status of biofuels mainly biodiesel along with the environmental impacts of particulate matter, greenhouse gas emissions originated from biodiesel.  相似文献   
10.
The contribution of spraying DDT and HCH for malaria control towards the contamination of bovine milk was investigated by analysing milk samples collected from preselected localities sprayed with either DDT or HCH in the Punjab. A direct correlation was found between the amounts of residues of these insecticides in milk and their typical usage pattern for the mosquito control programme. It is considered that these results may have significant bearing on the regulatory control of DDT and HCH residues in milk.  相似文献   
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