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11.
Borage, white mustard and phacelia, green manure plants currently used in agriculture to improve soil properties were cultivated for 10 wk on various polluted soils with metal(loid) concentrations representative of urban brownfields or polluted kitchen gardens. Metal(loid) bioavailability and ecotoxicity were measured in relation to soil characteristics before and after treatment. All the plants efficiently grow on the various polluted soils. But borage and mustard only are able to modify the soil characteristics and metal(loid) impact: soil respiration increased while ecotoxicity, bioaccessible lead and total metal(loid) quantities in soils can be decreased respectively by phytostabilization and phytoextraction mechanisms. These two plants could therefore be used for urban polluted soil refunctionalization. However, plant efficiency to improve soil quality strongly depends on soil characteristics.  相似文献   
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Majority of the people of Pakistan get drinking water from groundwater source. Nearly 40 % of the total ailments reported in Pakistan are the result of dirty drinking water. Every summer, thousands of patients suffer from acute gastroenteritis in the Rawal Town. Therefore, a study was designed to generate a water quality index map of the Rawal Town and identify the relationship between bacteriological water quality and socio-economic indicators with gastroenteritis in the study area. Water quality and gastroenteritis patient data were collected by surveying the 262 tubewells and the major hospitals in the Rawal Town. The collected spatial data was analyzed by using ArcGIS spatial analyst (Moran’s I spatial autocorrelation) and geostatistical analysis tools (inverse distance weighted, radial basis function, kriging, and cokriging). The water quality index (WQI) for the study area was computed using pH, turbidity, total dissolved solids, calcium, hardness, alkalinity, and chloride values of the 262 tubewells. The results of Moran’s I spatial autocorrelation showed that the groundwater physicochemical parameters were clustered. Among IDW, radial basis function, and kriging and cokriging interpolation techniques, cokriging showed the lowest root mean square error. Cokriging was used to make the spatial distribution maps of water quality parameters. The WQI results showed that more than half of the tubewells in the Rawal Town were providing “poor” to “unfit” drinking water. The Pearson’s coefficient of correlation for gastroenteritis with fecal coliform was found significant (P?P?P?相似文献   
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Oviposition site selection has a strong impact on the spatial distribution and sustenance of a species. This site selection by ladybirds (Coleoptera: Coccinellidae) is known to be well mediated amongst other factors by the oviposition deterring pheromones present in conspecific larval tracks. It would be also useful to the organism to be sensitive to heterospecific larval tracks, to protect from intraguild predation; however, this has not yet garnered much attention and there are only a few scattered studies with ambiguous results. The present study thus investigates the oviposition deterring effects of heterospecific presence and semiochemicals of heterospecific life stages (eggs, fourth instar larvae, pupae, adult males and females) of ladybird species, viz. Coccinella septempunctata, C. transversalis, Propylea dissecta on females of Menochilus sexmaculatus. Results reveal that the presence of all heterospecific life stages inhibits oviposition of M. sexmaculatus and the inhibition is density dependent. Semiochemicals of eggs, larval and adult tracks also show density-dependent inhibitory effects. The semiochemical-induced oviposition inhibition was stage specific with respect to the degree of inhibition. Of all heterospecific species tested, maximum and minimum oviposition deterrence of M. sexmaculatus was against C. septempunctata and P. dissecta, respectively. Comparison of our previously published results on oviposition inhibition in M. sexmaculatus due to conspecific presence with the current ones revealed increased inhibition in conspecific presence than heterospecific indicating ability to differentiate.  相似文献   
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Economic development, population growth, urbanization and climate change have led to an increasing water shortage across the globe. Ensuring water security under changing environment will be the greatest challenge for water resources managers in near future. In this paper, catastrophe theory based multi-criteria evaluation model has been proposed to assess water security under different management strategies to recommend the best water management strategy to achieve water security in the context of global environmental change. The assessment model involves future scenarios of climate change, population growth and economic development. Total 16 indicators related to climate, socio-economy and water availability and consumption have been proposed to measure water security under three management strategies viz. business-as-usual, water demand management and water supply management. The model has been applied to Yulin city of North West China to assess water security as well as to identify the water management strategy under changing environment. The results show that under business-as-usual situation the water shortage rate will reach up to 44 % by the year 2020 and up to 70 % by the year 2030 in Yulin. Water supply is required to increase by 41 % to meet the water demand under supply management strategy which is beyond the safe baseline rate. The study reveals that water demand management can reduce the gap between water supply and demand to a reasonable amount and therefore, can be considered as the most effective approach for adapting with environment change.  相似文献   
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Drought is one of the most frequent natural disasters in Bangladesh which severely affect agro‐based economy and people's livelihood in almost every year. Characterization of droughts in a systematic way is therefore critical in order to take necessary actions toward drought mitigation and sustainable development. In this study, standardized precipitation index is used to understand the spatial distribution of meteorological droughts during various climatic seasons such as premonsoon, monsoon, and winter seasons as well as cropping seasons such as Pre‐Kharif (March‐May), Kharif (May‐October), and Rabi (December‐February). Rainfall data collected from 29 rainfall gauge stations located in different parts of the country were used for a period of 50 years (1961‐2010). The study reveals that the spatial characteristics of droughts vary widely according to season. Premonsoon droughts are more frequent in the northwest, monsoon droughts mainly occur in the west and northwest, winter droughts in the west, and the Rabi and Kharif droughts are more frequent in the north and northwest of Bangladesh. It is expected that the findings of the study will support drought monitoring and mitigation activities in Bangladesh.  相似文献   
18.
A study was conducted to determine the effects of long-term exposure to carbofuran on erythrocyte and liver acetylcholinesterase (AChE) activity in Cyprinus carpio, and assess which tissue was more sensitive to pesticide exposure examining this enzyme. Fish were allowed to accilimatize in toxicant-free water for 24 days after 60-day exposure. AChE activity was determined with a spectrophotometer using acetylthiocholine iodide as a substrate in erythrocytes and liver. Enzymic activity of erythrocytes and liver decreased over time. A higher degree of enzyme inhibition was observed in erythrocyte compared to liver. The degree of enzyme inhibition was positively correlated with exposure time. When exposed fish were transferred to clean water, recovery was greater in erythrocytes than liver. Erythrocyte AChE activity recovered after 18 days, while it required 21 days in liver. The findings of this study indicate that erythrocyte AChE is more sensitive to carbofuran than liver. The greater sensitivity of erythrocyte AChE suggests that it may be more useful as a biomarker for monitoring status of pollution in freshwater bodies.  相似文献   
19.
Environmental Science and Pollution Research - Sunflower plants need nitrogen consistently and in higher amount for optimum growth and development. However, nitrogen use efficiency (NUE) of...  相似文献   
20.
Environmental Monitoring and Assessment - Few estuaries remain unaffected by water management and altered freshwater deliveries. The Caloosahatchee River Estuary is a perfect case study for...  相似文献   
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