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西北地区主要农药对蔬菜的污染评价方法及其应用 总被引:1,自引:0,他引:1
通过对兰州四区几种主要农药在蔬菜上的消解规律和农药起始残留浓度的研究,建立了两类不同剂型农药对蔬菜污染程度的评价方法?其评价参数为农药起始残留浓度?农药消解速度?最后一次施药至收获的间隔期和评价标准等因素?不同农药在不同蔬菜上的污染程度用蔬菜污染指数PI1和PI2表示? 相似文献
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以滇池流域呈贡县花卉、蔬菜的种植为研究对象,进行了化肥农药施用造成的面源污染调查,分析了N、P对滇池水体的污染,初步提出了控制对策。 相似文献
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本文针对增城市荔湖、仙村、南华等三个高尔夫球场施用农药的情况进行了调查.检测了所施用农药中剂量最多的两种(辛硫磷、克百威)在土壤中的残留量,结果表明两种农药施用后的残留量浓度均低于检出限,说明目前三个球场施用辛硫磷和克百威农药后对球场内土壤及其周围环境尚未造成明显的污染影响. 相似文献
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我国典型露地蔬菜生产中的温室气体排放 总被引:3,自引:0,他引:3
基于国家农业统计数据,以露地番茄、黄瓜、大白菜和萝卜为研究对象,应用生命周期评价(life cycle assessment,LCA)方法,定量化我国4种典型露地蔬菜生产中的净温室气体排放(net greenhouse gas emission,NGHGE),并比较蔬菜种类间、省域间净温室气体排放差异和分析减排措施.结果表明:我国典型露地蔬菜生产系统温室气体排放量远高于其带来的碳固定量,是净温室气体排放系统,生产单位面积露地番茄、黄瓜、大白菜和萝卜净温室气体排放(以CO_2-eq计)分别为4 149、 3 718、 3 780和2 427 kg·hm~(-2),不同种类露地蔬菜净温室气体排放差异大;我国典型露地蔬菜净温室气体排放空间差异大,其中,海南、云南、陕西和山东等省份番茄、黄瓜、大白菜和萝卜净温室气体排放高;肥料生产运输和施用是露地蔬菜温室气体排放的主要贡献因子,贡献率为86.8%~90.8%,因此改善肥料生产工艺降低肥料生产运输过程中的温室气体排放和根据露地蔬菜种类及种植地区优化肥料施用量是实现我国露地蔬菜可持续发展的重要措施. 相似文献
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近年来,随着蔬菜产销体制的改革,连作重茬面积的增加,大、小棚等保护地栽培面积的扩大,蔬菜病虫害也逐年加重。化学农药防治病虫害,仍是目前的主要手段;但是,不合理的施用农药,甚至滥用乱用,已造成了严重的后果。据我们对浙江13个县市的集市贸易随机抽样检测,25个蔬菜样品中,有12个农药残留超标,超标率达48%。其中8个高毒农药甲胺磷的残留量为0.27~8.8ppm,4个乐果的残留量为2.5~3.5ppm,超过国家允许标准近30倍。已停用10多年的有机氯农药,检出率也很高。138个土样中,检出率达98.55%。由于蔬菜中农药残留量超标,中毒事故时有发生。近年来,各级政府把“菜篮子”工程列入重 相似文献
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多种农药对胎儿发育的联合作用分析 总被引:6,自引:0,他引:6
分析了应城农村12万确定人群中1988-1989年2年期间出现妊娠出现妊局的妇女的前瞻性流行病学调查资料。共调查了5674位妇女。按照期家中使用的药品种数目,将研究对象分为0、1、2、3、4、5、≥和总组,计算了各组发生各种不良妊娠结局的相对度,结果表明。所暴露的农药品种数愈多,发生自然流产和出生缺陷的危险度愈大。农药品种数与它们对胎儿发育的不良影响之间存在“剂量-效应关系”。由此得出结论;多种农 相似文献
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Temporal trends in organophosphorus pesticides use and concentrations in river water in Japan, and risk assessment 总被引:1,自引:0,他引:1
We reviewed organophosphorus pesticide use in Japan between 1982 and 2016 using data from the National Institute of Environmental Studies. Organophosphorus pesticide concentrations in river water throughout Japan were taken from the literature, and risk assessments were performed for some organophosphorus pesticides based on risk quotients and hazard quotients. Assessments were performed for 20 common pesticides, including insecticides, fungicides, and herbicides. The amounts used decreased in the order: insecticides?>?herbicides?>?fungicides. Organophosphorus insecticide and fungicide use have decreased over the last four decades, but organophosphorus herbicide use has increased. During this period, annual organophosphorus pesticide use was the highest for chlorpyrifos (105,263?tons/year) and the lowest for glyphosate-sodium (8?tons/year). The ecotoxicological risk assessment indicated that diazinon and fenitrothion posed strong risks to the Japanese aquatic environment, and chlorpyrifos and malathion have moderate risks. None of the pesticides that were assessed posed significant risks to humans. Continued use of organophosphorus pesticides in Japan may cause strong risks to aquatic environments. These risks should be reassessed periodically. 相似文献
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Organic pesticides have been used for more than 50 years, and have made a major contribution to the profound alteration of agricultural practice which has occurred during this period. Among the many effects arising from these developments in agriculture, various environmental changes have been identified, which have been the subject of considerable public debate and disagreement. Attention has focussed particularly on the popularly assumed adverse influence of pesticides on the natural flora and fauna. This review examines the position in the United Kingdom where interest in wildlife has always been extensive and where many amateur observations and professional scientific studies have been brought to bear on the problem. It differentiates between ‘direct’ effects which may be attributed to particular uses of certain compounds and ‘indirect’ effects normally arising from changes in habitat or food supply brought about by pesticides. The approach adopted has been to assess the effects of pesticide use on populations rather than attempting to place a financial estimate on any adverse environmental effect attributed to pesticides. Systems of surveillance are described and their ability to detect adverse effects is assessed. The difficulty of correlating such effects with pesticide use is examined. In general, it is concluded that other than for insects the levels of surveillance have been adequate to detect adverse effects on fauna and flora arising from pesticide use. Where direct effects have been discerned in the past, action has, where possible, been taken to rectify the position and it is suggested that this will continue. Overall there is little evidence that the survival of individual species is threatened by the direct effects of pesticides. Indirect effects are neither simple to delineate nor readily corrected and it is recommended that more research be carried out to develop the ability to assess their influence. 相似文献
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《Agriculture, ecosystems & environment》1986,16(2):129-148
One option for controlling the spread of pesticide resistance is the coordinated use of two or more pesticides. However, strategies using two pesticides are necessarily more diverse than those using a single pesticide, and inept application may result in resistance to both pesticides in the time when a single resistance would have arisen if a single pesticide had been used.This paper uses simple genetic models to assess the relative effectiveness of different multiple-pesticide application strategies. It is concluded that there are two basic advantages of multiple-pesticide attack: increased back selection and “redundant killing”. Back selection may be enhanced by any of the basic multiple attack strategies. Redundant killing is more effective if the dosages of the two pesticides are highly positively correlated (such that if a pest individual receives a higher dose of one pesticide than the population average, then it is likely to have received a higher than average dose of the second pesticide as well). Some limitations on redundant killing are discussed; these result from the selection of doubly-resistant genotypes (accompanied by extreme linkage disequilibrium between resistance genes). 相似文献
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Global pollinator declines have been attributed to habitat destruction, pesticide use, and climate change or some combination
of these factors, and managed honey bees, Apis mellifera, are part of worldwide pollinator declines. Here we exposed honey bee colonies during three brood generations to sub-lethal
doses of a widely used pesticide, imidacloprid, and then subsequently challenged newly emerged bees with the gut parasite,
Nosema spp. The pesticide dosages used were below levels demonstrated to cause effects on longevity or foraging in adult honey bees.
Nosema infections increased significantly in the bees from pesticide-treated hives when compared to bees from control hives demonstrating
an indirect effect of pesticides on pathogen growth in honey bees. We clearly demonstrate an increase in pathogen growth within
individual bees reared in colonies exposed to one of the most widely used pesticides worldwide, imidacloprid, at below levels
considered harmful to bees. The finding that individual bees with undetectable levels of the target pesticide, after being
reared in a sub-lethal pesticide environment within the colony, had higher Nosema is significant. Interactions between pesticides and pathogens could be a major contributor to increased mortality of honey
bee colonies, including colony collapse disorder, and other pollinator declines worldwide. 相似文献
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采用田间模拟施药与气相色谱法研究了7种拟除虫菊酯农药在茶园生态环境中的降解动态,茶叶加工过程中的降解和泡茶过程的浸出率及其主要影响因子。根据实验结果推算出通过饮茶进入人体的农药量,结合农药的毒理特性,对拟除虫菊酯农药在茶园生态环境中应用的安全性进行了综合评价。结果表明,拟除虫菊酯农药在茶园中应用的安全性显著高于有机磷农药,在拟除虫菊酯农药之间,其安全性也有较大差异。本研究不仅为茶园使用农药的选择提供了依据,而且首次提出了一种农药对人体安全性的定量评价体系。 相似文献
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湘江流域土壤中有机氯农药的残留规律 总被引:1,自引:0,他引:1
2004年5月采集了湘江流域51个样品,用AES萃取技术,使用GC-MS方法测定了样品中的六氯苯(HCB)、滴滴涕(DDTs)、氯丹、艾氏剂、狄氏剂、异狄氏剂、七氯和灭蚁灵等有机氯农药(OCPs). 结果表明:HCB和DDTs的检出率为100%,氯丹和灭蚁灵的检出率较低,艾氏剂、狄氏剂、异狄氏剂和七氯未检出,说明HCB和DDTs曾在湘江流域广泛施用. w(OCPs)平均值为145.49 μg/kg,其中w(DDTs)占w(OCPs)的90.9%,且有些土壤样品中w(DDT)/w(DDE+DDD)较大,说明DDTs曾作为湘江流域的主要杀虫剂施用过,并且近期仍然有输入. 农药残留量与农药的施用量成正比,农药施用量高的衡阳地区,其土壤中的农药残留量最高. 不同使用功能的土壤中有机氯农药的残留量不同,表现为旱地中的残留量高于水稻地,蔬菜地中以辣椒地的残留量最高. 相似文献
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传统有机磷、有机氯农药具有高毒性、持久性和环境激素效应,处于痕量和超痕量浓度水平都可能给人类生命健康和生态环境带来严重威胁和风险。由于农药及其副产物的历史残留、累积及跨界迁移和分布,农药厂搬迁厂址用于房地产开发场地环评具有很大困难。结合南方某市一大型农药厂搬迁厂址用于房地产开发项目的案例,探讨了该类场地评价中基础资料的搜集方法和环评中应遵循的理念和原则。 相似文献
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为阐明我国东南地区典型饮用水源地农药类微污染物的污染特征及生态风险,检测评估了某省7个水库的苯并咪唑类、酰胺类、三唑类和有机磷类等19类共55种常用农药的检出频率、检出浓度以及每种农药对于绿藻、水蚤和鱼类这3种不同营养级生物的风险商.在分析的55种农药中,多菌灵和乙草胺的检出频率为100%,12种农药的检出频率在80%以上.多菌灵的检出浓度最高(77.7 ng·L-1),其次是乙草胺(51.6 ng·L-1).风险评估结果显示,大部分农药在目标区域都处于低风险状态.对于3种生物来说,乙草胺是绿藻的风险主导型农药,而多菌灵是鱼类和水蚤的风险主导型农药. 相似文献