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1.
在构建邻里效应对农户生物农药施用行为影响的理论模型基础上,利用鄂、赣、浙三省农户的调研数据,实证检验了邻里效应对农户生物农药施用行为的影响,在此基础上,进一步讨论了邻里效应促使稻农施用生物农药的条件与内在作用机制。结果表明:第一,55.76%的样本农户施用过生物农药,且施用生物农药的农户有较强的邻里关系。第二,邻里效应对农户生物农药施用行为有显著的正向影响,且强邻里效应的农户生物农药平均施用量要显著高于弱邻里效应农户。第三,邻里效应对稻农生物农药施用行为的影响存在条件限制,对高收入农户和规模户而言,邻里效应的影响不显著。第四,邻里效应对农户生物农药施用行为有显著直接作用,也通过降低信息搜寻成本和有效规避农业生产风险两条路径间接影响农户生物农药施用行为。  相似文献   

2.
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   

3.
农药在大棚蔬菜上的残留消解   总被引:10,自引:1,他引:10  
通过对6种农药在7种大棚作物上的共14次农药残留消解试验,及与露地作物所作的比较表明,除粉锈宁在大棚草莓上的消解外,农药在大棚蔬菜上的残留消解速度要慢于露地蔬菜,大棚空间农药沉降于蔬菜,是消解慢的重要原因,而环境条件对消解的影响程度还需进一步研究。该文指出,消解慢和大棚空气中浓度高;是大棚生产中两个突出的农药污染问题,前者导致上市大棚蔬菜的农药超标率高,后者为农事操作人员带来了恶劣的工作条件,需采  相似文献   

4.
The impact of effluent irrigation on the transformation and mobility of organic contaminants is poorly understood. The objectives of this review paper are: (i) to discuss the fundamental processes influencing the transformation and transport of pesticides in soil; (ii) to present a critical analysis of the impact of effluent irrigation on the transformation and transport of pesticides in soils; (iii) to suggest research areas that need attention. Effluent irrigation affects the fate of pesticides through its direct effect on the transformation and transport of pesticides that are already present at the irrigation sites, and its indirect effect on soil properties that are important in controlling the transformation and transport of organic contaminants. It has often been noticed that the effluent-derived dissolved organic matter (DOM) facilitates the movement of soil-borne pesticides by forming soluble pesticide complexes, and enhances their biodegradation by providing energy sources for the microorganisms that are involved in pesticide degradation. However, the results of field and laboratory experiments that examined the effect of effluent irrigation on the fate of pesticides are inconsistent; in some cases reduced mobility resulting from enhanced pesticide sorption has been observed, but enhanced pesticide mobility has also been reported. The inconsistency may be related to the inherent spatial variability of soil properties and/or the heterogeneity of effluent quality. For example, effluents vary in the nature and concentration of DOM that play a vital role in the degradation, sorption and transport behaviour of pesticides. Similarly, they vary in the concentrations of solvents and surfactants that have been shown to impact sorption and transport of organic contaminants. Field-based investigations on the impact of effluent irrigation on pesticide fate coupled with an accurate characterisation of the effluent are urgently required to assess the long-term risk associated with effluent irrigation in relation to pesticide transformation and transport.  相似文献   

5.
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   

6.
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   

7.
Pesticide use in agriculture can cause undesirable effects on humans and the natural environment. One of the objectives of integrated agriculture is the elimination or reduction of possible sources of environmental pollution such as pesticides. To achieve this objective, farmers need a method to assist them in estimating the environmental impact of pesticide use. This paper addresses a two-part question: what factors should be taken into consideration to assess pesticide environmental impact, and how can impact be quantified? As the environmental impact of a pesticide depends on its dispersion in the environment and on its toxicological properties, the literature on these topics is reviewed to address the first part of the question. To address the second part of the question, six recent approaches to assess the impact of pesticides on the environment are compared regarding choice, transformation and aggregation of input parameters. The use of simulation models to assess environmental impact is discussed.  相似文献   

8.
IntroductionPollution of natural waters with waste effluentsarising from various industries has become a seriousproblem in India.In Rajasthan particularly,textilemills represent an important economic sector.Effluents from these textile and other dye-relat…  相似文献   

9.
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   

10.
欧盟不同环境领域环境政策发展趋势分析   总被引:2,自引:0,他引:2  
在回顾欧盟环境政策发展历程的基础上,重点论述了2000年以来欧盟在水环境保护、空气污染防治、噪声污染防治、固体废物管理、化学品与杀虫剂管理、野生动植物保护和土壤保护等领域的政策发展趋势,以及为实施其环境政策所引入的各种辅助手段.  相似文献   

11.
紫外光和基于紫外光的高级氧化工艺降解农药的研究进展   总被引:2,自引:1,他引:1  
由于农药的环境持久性及毒性,饮用水源中的农药微污染日益受到水处理行业的关注.在众多水处理工艺中,紫外光及基于紫外光的高级氧化工艺因其灭菌效率高、产生消毒副产物少等特点受到广泛关注.本文综述了紫外光及其相关高级氧化工艺对多类广泛使用的农药(包括有机氯、有机磷、氨基甲酸酯、氯乙酰胺和三嗪等)的降解效果,详细讨论了农药的降解...  相似文献   

12.
The fate, exposure and effects model USES-LCA 2.0 has been adapted to calculate characterisation factors for toxic chemicals emitted under Australian conditions. Normalisation data for Australian ecotoxicity and human toxicity have been calculated using the emission data from the National Pollutant Inventory (2002/2003) and pesticide use information. National freshwater ecotoxicity and terrestrial ecotoxicity impacts are dominated by pesticide use. Total marine ecotoxicity is dominated by fluoride, originating from air emissions from the electricity supply and non-ferrous metals' (and products) manufacturing industry sectors and water emissions from the sewerage treatment plants. The human toxicity is primarily attributed to the inhalation of toxic metal dust. There is a large diffuse component (primarily from road dust) and the remaining human toxicity contributions can be attributed to air emissions from the mining (non-ferrous metal ores), electricity supply and non-ferrous metals' (and products) manufacturing industry sectors. Future research should investigate the feasibility of combining NPI emissions with regional (climate) specific characterisation factors.  相似文献   

13.
Environmental pollution has become one of the greatest problems in the world, and the concerns about environmental pollutants released by human activities from agriculture and industrial production have been continuously increasing. Although intense efforts have been made to understand the health effects of environmental pollutants, most studies have only focused on direct toxic effects and failed to simultaneously evaluate the long-term adaptive, compensatory and secondary impacts on health. Burgeoning evidence suggests that environmental pollutants may directly or indirectly give rise to disordered element homeostasis, such as for iron. It is crucially important to maintain concerted cellular and systemic iron metabolism. Otherwise, disordered iron metabolism would lead to cytotoxicity and increased risk for various diseases, including cancers. Thus, study on the effects of environmental pollutants upon iron homeostasis is urgently needed. In this review, we recapitulate the available findings on the direct or indirect impacts of environmental pollutants, including persistent organic pollutants (POPs), heavy metals and pesticides, on iron homeostasis and associated adverse health problems. In view of the unanswered questions, more efforts are warranted to investigate the disruptive effects of environmental pollutants on iron homeostasis and consequent toxicities.  相似文献   

14.
The deletrious effects of chemical pesticides on many plant and animal populations have been described. Rapidly increasing costs of convenient energy sources have increased cost-benefit ratios of chemical pesticides used. We compared biological control techniques versus chemical pesticides for inputs of human labor, machinery, and fuel per hectare at each pertinent step of the production procedure. Three pest-crop systems were selected and all applicable factors converted into kilocalories of energy required. These were: (1) citrus-red scale (Aonidiella aurantii), using oil as a chemical and the predator wasp, Aphytis melinus as a biological control; (2) greenhouse cucumbers-white fly (Trialeurodes vaporariorum), using Orthene or the wasp, Encarsia formosa; (3) tomato-hornworm (Manduca quinquemaculata) using Sevin or the bacterium, Bacillus thurengiensis.For citrus-red scale, the pesticide required 5 248 405 kcal, the use of A. melinus 100 793 kcal; for cucumber-white fly the pesticide required 29 300 kcal, E. formosa 154 500 kcal; for tomato-hornworm the pesticide 26 693, B. thurengiensis 207 240 kcal.  相似文献   

15.
调查云南农民在冬春季蔬菜种植过程中的农药施用状况。随机抽取668名农户进行问卷调查,内容涉及施用农药的种类、频次、施药安全间隔期等。从调查中发现云南农村施用于蔬菜的农药种类共计40余种,以有机磷类杀虫剂为主;国家明令禁止的农药违规施用还在发生;部分农药的安全间隔期违规现象同样比较严重。并分析原因提出减少农村蔬菜生产过程中农药污染的看法。  相似文献   

16.
11种有机磷农药对海洋微藻致毒效应的研究   总被引:17,自引:0,他引:17  
通过研究不同盐度条件下11种有机磷农药对扁藻的相对增长率和叶绿素a含量的影响,得到了S=30和S=20时的半数有效浓度,并比较其大小。盐度作为环境因子,影响到有机磷农药的毒性。研究发现,遥有机磷农药在低浓度时出现一定限度的促生长作用;容易进攻细胞膜的有机磷农药对扁藻的致毒性相对较强;此外,有机磷农药的毒性大小与其结构密切相关含有苯环结构的有机磷农药毒性大小不含有苯 有机磷农药的毒性。  相似文献   

17.
昆虫对拟除虫菊酯农药的抗性研究进展   总被引:2,自引:0,他引:2  
拟除虫菊酯是继有机氯、有机磷和氨基甲酸酯之后具有生物活性优异、环境相容性较好的一大类杀虫剂,在防治卫生害虫和农作物害虫中占有重要地位。然而随着拟除虫菊酯农药的广泛使用,害虫普遍对其产生了不同程度的抗药性。文章就此综述了昆虫对拟除虫菊酯农药的抗药性现状、抗药性产生的原因及机制,以及昆虫对拟除虫菊酯农药与其他农药的交互抗性、昆虫的抗药性遗传和对昆虫抗药性进行监测的现行方法等国内外的研究进展。并对如何科学合理的使用拟除虫菊酯农药,及如何减缓昆虫对其产生抗性的措施进行了扼要的阐述,最后探讨了受农药影响所导致的昆虫基因多样性及生物多样性受损等问题。  相似文献   

18.
Excessive use of pesticides poses increased risks to non target species including humans. In the developing countries, lack of proper awareness about the toxic potential of pesticides makes the farmer more vulnerable to pesticide linked toxicities, which could lead to diverse pathological conditions. The toxic potential of a pesticide could be determined by their ability to induce genetic mutations and cytotoxicity. Hence, determination of genetic mutation and cytotoxicity of each pesticide is unavoidable to legislate health and safety appraisal about pesticides. The objective of current investigation was to determine the genotoxic and cytotoxic potential of Endosulfan(EN) and Lambda-cyhalothrin(LC); individually and in combination. 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide(MTT) assay was utilized to determine cytotoxicity, while two mutant histidine dependent Salmonella strains(TA98, TA100) were used to determine the mutagenicity of EN and LC.Moreover, mutagenicity assay was conducted with and without S9 to evaluate the effects of metabolic activation on mutagenicity. Even though a dose dependent increase in the number of revertant colonies was detected with EN against both bacterial strains, a highly significant(p 〈 0.05) increase in the mutagenicity was detected in TA98 with S9. In comparison, data obtained from LC revealed less mutagenic potential than EN. Surprisingly,the non-mutagenic individual-concentrations of EN and LC showed dose dependent mutagenicity when combined. Combination of EN and LC synergistically induced mutagenicity both in TA98 and TA100. MTT assay spotlighted comparable dose dependent cytotoxicity effects of both pesticides. Interestingly, the combination of EN and LC produced increased reversion and cytotoxicity at lower doses as compared to each pesticide, concluding that pesticide exposure even at sub-lethal doses can produce cytotoxicity and genetic mutations, which could lead to carcinogenicity.  相似文献   

19.
Pesticides are a well-known family of chemicals that have contaminated water systems globally. Four common subfamilies of pesticides include organochlorines, organophosphates, pyrethroids, and carbamate insecticides which have been shown to adversely affect the human nervous system. Studies have shown a link between pesticide exposure and decreased viability, proliferation, migration, and differentiation of murine neural stem cells. Besides human exposure directly through water systems, additional factors such as pesticide bioaccumulation, biomagnification and potential synergism due to co-exposure to other environmental contaminants must be considered. A possible avenue to investigate the molecular mechanisms and biomolecules impacted by the various classes of pesticides includes the field of -omics. Discovery of the precise molecular mechanisms behind pesticide-mediated neurodegenerative disorders may facilitate development of targeted therapeutics. Likewise, discovery of pesticide biodegradation pathways may enable novel approaches for water system bioremediation using genetically engineered microorganisms. In this mini-review, we discuss recently established harmful impacts of various categories of pesticides on the nervous system and the application of -omics field for discovery, validation, and mitigation of pesticide neurotoxicity.  相似文献   

20.
The introduction of genetically modified herbicide tolerant (GMHT) crops has raised concerns from both scientists and non-governmental organisations about possible effects on arable flora and fauna due to the changes in herbicide application and management that such crops involve. Three consecutive studies were performed, covering flora and fauna in fields of GMHT and conventional fodder beets over the season, at different locations and under different spraying regimes. At all locations and in the 3 years, a denser and more diverse weed flora and arthropod fauna were found in GMHT beets in early and mid-summer than in conventional beets when glyphosate-treatment occurred at or after label recommendation. Following the herbicide applications the GMHT fields had fewer weed species and seeds and lower weed densities and biomass than conventional fields. However, application of glyphosate earlier than recommended resulted in an extremely low weed diversity, density and biomass during the entire season. Timing of the first glyphosate applications, i.e. the duration of the herbicide free period, was essential in terms of biodiversity improvements. In the long term reduced production of weed seeds in GMHT fields may deplete the weed flora if the GMHT strategy becomes widely adopted.  相似文献   

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