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81.
Increasing on-farm crop diversity is one agroecological approach to enhancing food self-sufficiency that helps small-scale farmers keep their food systems stable by reducing risks associated with stressors, such as a pest outbreaks or droughts. But understanding how crop diversity and food self-sufficiency are related is unknown. To explore this complex relation, this study presents household data (n = 1664) from Nepal to test the hypothesis that families with high crop diversity enjoy greater household food self-sufficiency. Data are presented for three districts that are representative of three distinct agroecological regions of the country: (1) Sarlahi, which is affluent, market-oriented, and on the plains; (2) Makwanpur District in the hills, which has well-developed integrated farm production; and (3) the mountainous District of Humla, which has the poorest quality environment and is the most remote. Results show that in the Humla District, families with greater crop diversity were more self-sufficient. In contrast, farmers in Makwanpur, who have already established a high degree of crop diversity based on vegetable production, do not benefit from additional crop diversity in terms of their ability to provide for themselves. Finally, data from Sarlahi show that families’ food self-sufficiency benefits from crop diversification. We conclude that boosting crop diversity is a viable strategy for maintaining stability in food systems, but this varies depending on the accessibility of a farm and, in particular, access to markets.  相似文献   
82.
Environmental Science and Pollution Research - Contamination of environment and food from the prevalent spores and mycotoxins of Aspergillus niger has led to several diseases in humans and other...  相似文献   
83.
Geographic information system (GIS) has become one of the leading tools in the field of hydrogeological science that helps in assessing, monitoring, and conserving groundwater resources. Groundwater is a finite resource, which is being overexploited due to increase in demand over the years leading to decrease in its potentiality. In the present study, DRASTIC model has been used to prepare groundwater vulnerable zone in hard rock aquifer of granitic terrain. The main objective is to determine susceptible zone for groundwater pollution by integrating hydrogeological layers in GIS environment. The layers such as depth of aquifer, recharge, aquifer yield, soil type, topography, vadose zone, and transmissivity are incorporated in the DRASTIC model. The final output of the map shows that around 60% of the area falls under low to no risk of pollution zone. The high risk of pollution zones are mostly present towards the margin of southeastern periphery. The lower part of the basin as well as small area on northern side falls under moderate risk of pollution zone. For the assessment of groundwater pollution zone, 24 groundwater samples have been collected from different vulnerable zones. The chemical analysis of sample shows that the southeastern margin of basin has relatively high concentration of nitrate as compared to other parts of the basin. It is present in high pollution zone as well as moderate pollution zone. The present model can be used for assessment and management of groundwater.  相似文献   
84.
The study explains water quality of three important tributaries of the Ganga River in the middle Gangetic plains in India. Seasonal changes in the water quality of the studied rivers: Gandak, Ghaghra, and Sone were observed. During monsoon, several water quality parameters show considerable changes due to increased runoff from the catchments and other seasonal factors. Multivariate discriminant analysis delineated a few parameters responsible for temporal variation in water quality. Seasonal variation in water quality of the Gandak River was rendered by seven parameters??turbidity, sulfate, pH, phosphate, water temperature, total alkalinity, and sodium, while total alkalinity and water temperature were responsible for seasonal discrimination in water quality of Ghaghra River. Water temperature, turbidity, total dissolved solids, total suspended solids, calcium, and phosphate were important for seasonal discrimination in water quality of Sone River. The seasonal changes in water quality of the rivers were due to seasonal effects and catchment characteristics. The discriminant functions classified most of the cases correctly.  相似文献   
85.
Environmental Science and Pollution Research - The photovoltaic (PV) for irrigation system is an emerging technology to harness the solar energy. The performance of the PV modules depends on the...  相似文献   
86.
Environmental Science and Pollution Research - The present work aims to investigate seasonal variations in air pollution levels in Lucknow and assess the ambient air quality of the city together...  相似文献   
87.
Environmental Science and Pollution Research - Chromite ore processing residues (COPR) are real environmental threats, leading to CrO42-, i.e., Cr (VI) leaching into groundwater. It is of serious...  相似文献   
88.
The sustainable development of the limited groundwater resources in the tropical island requires a thorough understanding of detail hydrogeological regime including the hydrochemical behavior of groundwater. Detail analysis of chemical data of groundwater helps in assessing the different groundwater zone affected by formation as well as sea water. Groundwater and saline water interaction is better understood using groundwater major ion chemistry over an island aquifer. Multivariate methods to analyze the geochemical data are used to understand geochemical evolution of groundwater. The methods are successfully used to group the data to evaluate influence of various environs in the study area. Various classification methods such as piper, correlation method, and salinity hazard measurements are also employed to critical study of geochemical characteristics of groundwater to identify vulnerable parts of the aquifer. These approaches have been used to successfully evaluate the aquifer zones of a tiny island off the west coast of India. The most part of island is found to be safe for drinking, however some parts of island are identified that are affected by sea water ingress and dissolution of formation minerals. The analysis has successfully leaded to identification of that part of aquifer on the island which needs immediate attention for restoration and avoids further deterioration.  相似文献   
89.
ABSTRACT

Air quality model simulations constitute an effective approach to developing source-receptor relationships (so-called transfer coefficients in the risk analysis framework) because a significant fraction of particulate matter (particularly PM2.5) is secondary (i.e., formed in the atmosphere) and, therefore, depends on the atmospheric chemistry of the airshed. In this study, we have used a comprehensive three-dimensional air quality model for PM2 5 (SAQM-AERO) to compare three approaches to generating episodic transfer coefficients for several source regions in the Los Angeles Basin. First, transfer coefficients were developed by conducting PM2.5 SAQM-AERO simulations with reduced emissions of one of four precursors (i.e., primary PM, sulfur dioxide (SO2), oxides of nitrogen (NOx), and volatile organic compounds) from each source region. Next, we calculated transfer coefficients using two other methods: (1) a simplified chemistry for PM2.5 formation, and (2) simplifying assumptions on transport using information limited to basin-wide emission reductions. Transfer coefficients obtained with the simplified chemistry were similar to those obtained with the comprehensive model for VOC emission changes but differed for NO and SO emission changes. The differences were due to the parameterization of the rates of secondary PM formation in the simplified chemistry. In 90% of the cases, transfer coefficients estimated using only basin-wide information were within a factor of two of those obtained with the explicit source-receptor simulations conducted with the comprehensive model. The best agreement was obtained for VOC emission changes; poor agreement was obtained for primary PM2.5.  相似文献   
90.
Impact of thermal discharge from a coastal power station (Madras Atomic Power Station, southeast coast of India) on the spatial variability of Donax cuneatus abundance was assessed to determine the impact boundary. Totally, 20 sites were selected both on south and north side in increasing spatial scale from mixing zone, 12 locations were selected toward south side at a distance from 0 (near mixing point) to 2,000 m and eight location were selected toward north from the effluent mixing zone. Mean water temperature along the coast ranged from 29.1 ±0.15°C to 31.2 ± 0.15°C. Total organic carbon content in the sediment ranged from 0.27% to 0.70%. D. cuneatus population on the swash zone was ranged between 1.3 ± 1.5 and 88.3 ± 9.6 m???2. Meager population of wedge clam was observed up to 100 m (S100) south from mixing point and abundance gradually increased in different spatial scale. Comparatively high abundance was observed from S400 and reached maximum at S1000 (64.0 ± 3.6 m???2). Similar pattern was observed on north side too but less abundance was observed only up to 80 m (N80). Maximum abundance was observed at control location C3-N500 (88.3 ± 9.6 m???2). Forty meters on either side of discharge point was highly impacted, 80 to 100 m toward plume flow (south) was moderately impacted, and 80 m north of mixing point also witnessed moderate impact. After 100 m (N100), north was not affected by effluents, whereas between 100 and 400 m, south was influenced slightly. Multivariate clustering pattern on the environmental variables of all sampling locations and population trend of D. cuneatus at those stations showed similarity. Present investigation unambiguously showed that the abundance pattern of D. cuneatus on the sandy beach of east coast of Kalpakkam is not governed by single major factor but due to the result of multiple interacting factors. The population size of the wedge clam with reference to the effect of power plant effluents and other features of habitats of the beach ecosystem are also discussed.  相似文献   
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