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981.
982.
983.
干旱是威胁我国及世界农业发展的自然灾害之一,利用遥感技术进行干旱监测与评估已成为一种重要而有效的手段。2008年10月至2009年2月,我国北方地区出现了大面积的持续干旱,给冬小麦的生长造成了严重的影响。基于2000年至2009年Terra卫星MODIS传感器8天合成的地表反射率数据,结合地面实测土壤水分和实地调研数据,利用距平植被指数(AVI)和距平水分指数(AWI)对我国北方冬小麦主产区的干旱程度进行了分级,对干旱的发生、发展和时空变化情况进行了连续监测,得到了该时期的旱情分布结果:2008年10月份以后旱情逐渐加重,2009年1月下旬各地旱情达到了最严重的程度。研究表明,AWI对干旱的反应比AVI敏感而且准确。 相似文献
984.
In vitro fertilization (IVF) is one of the most important treatments of infertility to provide a chance of conceiving. In IVF treatment, sperm are washed and motile sperm are isolated with sperm washing media (SWM) for the purpose of fertilization; fertilized ova are then incubated for a maximum of 5 or 6 d in media for IVF (IVFM). The exposure of fertilized ova to chemicals via such media has not been studied. We determined the concentrations of two contaminants; di(2-ethylhexyl)phthalate (DEHP) and its hydrolyzed product mono(2-ethylhexyl)phthalate (MEHP) in IVFM, SWM, and protein sources (PS: human serum albumin or serum substitute) for IVFM and SWM. The DEHP and MEHP in these media were extracted by a liquid-liquid extraction method and their concentrations determined by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Fifteen IVFM, nine SWM, and six PS obtained in Japan were examined. The concentrations of DEHP and MEHP in IVFM and SWM were <10-114 and <2.0-263 ng mL−1, respectively. The concentrations of both DEHP and MEHP were higher in the media containing PS than in those without PS. Either MEHP alone or both DEHP and MEHP were detected in PS. The concentrations of DEHP and MEHP in PS were <10-982 and 47.0-1840 ng mL−1, respectively. The DEHP and MEHP detected in these media were derived from PS. This is the first study on the chemical contamination of IVFM, SWM, and PS. 相似文献
985.
This paper invokes the theory of planned behavior (TPB) as a diagnostic tool to explain an existing public education program's limited success at improving river water quality in the City of Perth, Western Australia. A reflective, client-driven research approach was used. A facilitated expert workshop defined an environmental problem (excess nutrients leaving gardens and entering waterways) and a desired behavior (residents purchasing environmentally sensitive fertilizer) to address the problem. A TPB-based belief elicitation survey captured respondents' beliefs regarding the desired behavior. The findings suggest respondents were aware of the links between purchasing environmentally sensitive fertilizer and river water quality. However, this behavior is compromised by the challenges in identifying appropriate products, product quality concerns, and cost. Viewing the content of a public education program through the lens of the TPB reveals insights into how and why the program fell short in achieving one of its key behavioral change goals. 相似文献
986.
本文主要针对广州市城中村进行了全面梳理,按照其功能类型进行分类,并在此基础上对典型城中村污水治理现状进行了实证调研。从现实来看,广州市大量的城中村污水治理不可能在短时间内完成,如果缺乏系统的规划治理,新的城中村依然还会出现污水治理问题,因此,解决城中村污水治理问题必须以现实情况为着眼点,找到破解当前治理的路径,才能完成国家和广东省对广州黑臭河涌治理部署要求,从而实现广州水环境根本好转的目标。 相似文献
987.
Martina Galdíková Katarína Šiviková Beáta Holečková Ján Dianovský Monika Drážovská Viera Schwarzbacherová 《Journal of environmental science and health. Part. B》2013,48(10):698-707
The potential genotoxic effect of thiacloprid formulation on bovine peripheral lymphocytes was evaluated using the comet assay and the cytogenetic endpoints: chromosome aberrations (CAs), sister chromatid exchanges (SCEs) and micronuclei (MNi). Whole blood cultures were treated with the insecticide at concentrations of 30, 60, 120, 240 and 480 μg mL?1 for 24, 48 h and/or 2 h of incubation. A statistically significant increase in the frequency of DNA damage, as well as in unstable chromosome aberrations (% breaks) were found after exposure to the insecticide at concentrations ranging from 120 to 480 μg mL?1 (P < 0.05, P < 0.01, P < 0.001). For the detection of stable structural chromosome aberrations (e.g., translocations) and numerical aberrations by the FISH method, three whole chromosome painting probes for bovine chromosomes 1, 5 and 7 (BTA1, BTA5 and BTA7) were used in our experiments. We observed numerical aberrations, but without any statistical significance. Regarding the sister chromatid exchanges, no significant elevation in the SCE frequencies was found after 24-h exposure to the insecticide. A dose-related response in the SCE induction was obtained in bovine cultures after the prolonged time of exposure (48 h) to thiacloprid formulation at concentrations ranging from 120 to 480 μg mL?1 in each donor (P < 0.05, P < 0.01), which was associated with a reduction of the PI (P < 0.05, P < 0.01). The insecticide failed to produce MNi; however, a significant reduction of CBPI was observed. Using real-time PCR, a decrease in the expression of bovine glutathione S-transferase M3 (GSTM3) was detected at the lowest dose. The higher concentrations of thiacloprid formulation caused an increase in the mRNA expression. 相似文献
988.
Uptake of uranium and thorium by native and cultivated plants 总被引:2,自引:0,他引:2
Shtangeeva I 《Journal of environmental radioactivity》2010,101(6):458-6946
Large part of available literature on biogeochemistry of uranium and thorium refers to the studies performed either in highly contaminated areas or in nutrient solutions that have been artificially ‘spiked’ with radionuclides. Effects of background levels of natural radioactivity on soil-grown plants have not been studied to the same extent. In this paper, we summarised results of greenhouse and field experiments performed by the author from 2000 to 2006. We examined some of the factors affecting transfer of U and Th from soil to plants, differences in uptake of these radionuclides by different plants, relationships between U and Th in soil and in plants, and temporal variations of U and Th in different plant species. Concentrations of radionuclides (critical point for experimental studies on biogeochemistry of U and Th - rare trace elements in non-contaminated regions) and essential plant nutrients and trace elements were determined by instrumental neutron activation analysis. 相似文献
989.
Biljana Mirković Milan Stević Jovana Hrustić Milica Mihajlović Goran Delibašić 《Journal of environmental science and health. Part. B》2013,48(12):845-850
Field isolates of Didymella applanata, the causal agent of spur blight of raspberry, were evaluated in vitro for their sensitivity to mancozeb, chlorothalonil, captan, fluopyram, boscalid and difenoconazole. A total of 10 isolates, collected during 2013 at five localities in the major raspberry growing region in Serbia, and characterized as copper hydroxide, dithianon, and tebuconazole (sensitive), pyraclostrobin (sensitive or highly resistant) and fluazinam (sensitive or moderately resistant), were used in this study. The EC50 values for the isolates ranged from 1.33 to 2.88 mg L?1 for mancozeb, from 3.18 to 6.65 mg L?1 for chlorothalonil, from 15.75 to 24.69 mg L?1 for captan and from 1.80 to 8.20 mg L?1 for fluopyram. The narrowest range of EC50 values was recorded for difenoconazole (0.23–0.49 mg L?1), whereas the widest range was obtained for boscalid (4.49–49.25 mg L?1). The calculated resistance factors showed that all D. applanata isolates were sensitive to mancozeb, chlorothalonil, captan, and difenoconazole. Four isolates were moderately resistant to boscalid, while three of them were also moderately resistant to fluopyram. This finding of moderately resistant isolates to these SDHI fungicides indicates a possible cross-resistance which should be clarified in further investigations. 相似文献
990.
Yu-Chi Weng Takeshi Fujiwara Yuzuru Matsuoka 《Journal of Material Cycles and Waste Management》2009,11(2):110-122
Industrialization and urbanization result in significant changes in lifestyle. These lifestyle changes seem to lead to unsustainable
consumption patterns and increase the generation of various kinds of environmental loads, especially the amount of municipal
solid waste (MSW). Taiwan is a small island with scarce natural resources. The economic development in Taiwan has resulted
in the generation of large amounts of MSW. As a result, the Taiwan Environmental Pollution Administration (TEPA) has produced
regulations for waste minimization and has imposed several important policy measures that have successfully reduced the MSW
discard rate in recent years and have established a public recycling network as a part of the MSW collection. Nowadays, the
objective of the MSW policies in Taiwan is to develop a “zero-waste society.” This article aims to review the MSW management
progress in Taiwan and to project future MSW discards up to 2011 based on the national plan and assumed scenarios for socioeconomic
variables. According to the analysis results, a more sustainable consumption pattern can be proposed and the corresponding
MSW management system can be planned so as to develop a low-waste-discard society. 相似文献