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191.
The Indian desert, the Thar Desert, has its own importance and specific characteristics with respect to endemic and medicinal plants. Forty-five plant species are considered to be rare and/or endangered. The desert has a large number of plants of economic importance and medicinal use. The Thar Desert is thickly populated in comparison to other hot deserts of the world. 17.44 million people and 23.33 million livestock are recorded from the region. These populations exert pressure on the biological resources of the Thar Desert causing a lack of sustainability and necessitate conservation of biodiversity actions.  相似文献   
192.
ABSTRACT: A three‐dimensional fractured medium flow model was developed for the Bear Creek Valley (BCV) S‐3 site of the Oak Ridge Reservation (ORR) using SWIFT III. The numerical modeling for this site focused on a conceptual model established through the analysis of heterogeneous geologic units and matrix fracture properties of the subsurface in the BCV area. The SWIFT III modeling analysis was based on the previous modeling studies that used MODFLOW and MODPATH. A rigorous calibration was obtained first by comparing simulated results with the existing data on ground water levels and then by comparing pumping test results with the simulated ground water levels. A satisfactory agreement between observed and simulated results was obtained. The calibrated model was used to determine sustained yield from a ground water interceptor trench. Different withdrawal rates were used to simulate the performance of the trench for the sustained withdrawal of ground water.  相似文献   
193.
Nutrient Ioadings were measured for surface seawater and bottom sediments of semi-intensive and improved extensive shrimp culture pond, adjacent estuary, and fallow land in the south-east coastal region of Bangladesh during August, 2000--January, 2001 to evaluate the impact of shrimp culture. The mean levels of nutrients found in the pond surface water were 108.780 mg/L for CaCO3, 0.526 mg/L for NH4^ -N, 3.075 wt% for organic carbon, 7.00 mg/L for PO4-P, 5.57 mg/L for NO3-N, and 7.33 mg/L for chlorophyll-a. The maximum mean value of H2S(0.232 mg/L) was found in estuarine water. Nutrients loading were found to be decreased with distance from the shrimp farm discharge unit in estuarine water. The mean level of organic matter, total nitrogen, and organic carbon were found in higher concentrations in sediments of cultured pond compared to bottom soil of adjacent fallow land at the same elevation. Extractable Ca values were found in higher concentration(550.33 ppt) in adjacent fallow land, as the shrimps for molting in shrimp ponds use extractable Ca. The relation between seawater H2S value and sediment pH ( r= -0.94); sediment organic carbon and sediment pH values ( r= -0.76), sediment total nitrogen and sediment pH ( r = - 0.74) were found to be highly negatively correlated. Whereas the relation between seawater H2S value and sediment total nitrogen ( r= 0.92), water NH4^ -N and sediment pH ( r = 0.66) were found to be positively correlated. The results revealed that load of nutrients at eutrophic level in estuarine water, and decrease of soil pH; leading to acid sulphate soil formation indicates a negative impact of shrimp culture.  相似文献   
194.
Environmental Science and Pollution Research - Fluvoxamine, a selective serotonin re uptake inhibitor, is used to treat depression. The aim of present study was to evaluate fluvoxamine in acute...  相似文献   
195.
Environmental Science and Pollution Research - The viral RNA of SARS-Coronavirus-2 is known to be contaminating municipal wastewater. We aimed to assess if COVID-19 disease is spreading through...  相似文献   
196.
Environmental Science and Pollution Research - Biomass energy is an important source of energy consumption. It is a renewable, abundant, and easily produced energy source. Its usage supports...  相似文献   
197.
Environmental Science and Pollution Research - A comprehensive study was conducted to appraise the concentrations of 30 endocrine disrupting pesticides (EDPs) in soil and vegetable samples...  相似文献   
198.
Environmental Science and Pollution Research - Emerging economies are experiencing considerable economic changes due to change in energy demand and CO2 emissions. To explore the link between energy...  相似文献   
199.

Over the last few decades, the atmospheric carbon dioxide emission has been amplified to a great extent in Pakistan. This amplification may cause global warming, climate change, and environmental degradation in Pakistan. Consequently, ecological condition and human life may suffer in the near future from these indicated threats. Therefore, an attempt was made to test the relationship between globalization and carbon dioxide emissions in case of Pakistan. The study covers the time series data over the period of 1975–2014. We employed modern econometric techniques such as Johansen co-integration, ARDL bound testing approach, and variance decomposition analysis. Results of the Johansen co-integration test show that there is a significant long-run relationship between carbon dioxide emissions and globalization. The long-run elasticities of the ARDL model show that a 1% increase in economic globalization, political globalization, and social globalization will increase carbon dioxide emissions by 0.38, 0.19, and 0.11%, respectively. Further, our findings reveal that the environmental Kuznets curve (EKC) hypothesis prevails an inverted U-shaped relationship between carbon dioxide emission and economic growth. Therefore, the EKC hypothesis is valid in the presence of globalization. The diagnostic test results show that the parameters of the ARDL model are credible, stable, and reliable in the current form. Finally, variance decomposition analysis displays that economic, political, and social globalization are contributing significantly to carbon dioxide emissions in Pakistan.

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200.
This paper reports a sensitive and cost effective method of analysis for aflatoxins B1, B2, G1 and G2. The sample preparation method was primarily optimised in peanuts, followed by its validation in a range of peanut-processed products and cereal (rice, corn, millets) matrices. Peanut slurry [12.5 g peanut + 12.5 mL water] was extracted with methanol: water (8:2, 100 mL), cleaned through an immunoaffinity column and thereafter measured directly by ultra-performance liquid chromatography-fluorescence (UPLC-FLD) detection, within a chromatographic runtime of 5 minutes. The use of a large volume flow cell in the FLD nullified the requirement of any post-column derivatisation and provided the lowest ever reported limits of quantification of 0.025 for B1 and G1 and 0.01 μg/kg for B2 and G2. The single laboratory validation of the method provided acceptable selectivity, linearity, recovery and precision for reliable quantifications in all the test matrices as well as demonstrated compliance with the EC 401/2006 guidelines for analytical quality control of aflatoxins in foodstuffs.  相似文献   
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