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风险一般指遭受损失、损伤或毁坏的可能性。生态风险是生态系统及其组分所承受的风险。生态风险评价是对产生不利的生态效应的可能性进行评价的过程。农药生态风险评价是采用生态风险评价技术评价农药给整个生态环境带来的风险。本文就农药生态风险评价的基本概念、过程和模型、内容和方法以及农药生态风险的评价研究现状进行了述评。 相似文献
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目前三七[Panax notoginseng(Burk.) F. H. Chen]根腐病尚无病害分级标准,为发现抗病种质资源和评估病害防控效果,本研究建立了用于三七根腐病的田间分级标准。从云南省文山州收集200株发生根腐病的三年生植株,筛选获得具有代表性不同腐烂程度的98株样本,通过对表面腐烂占比、横截面腐烂、支须根腐烂、芽及芦头腐烂5项指标进行描述,采用SPSS21进行样本聚类分析,制定了如下用于三七根腐病的田间分级标准:0级,健康,无症状;1级,腐烂仅发生在块根表面、且0<腐烂面积占比≤10%,或腐烂已扩展至内部且5%<腐烂面积占比≤10%;2级,腐烂已扩展至内部、且10%<腐烂面积占比≤40%,支须根无腐烂;3级,腐烂已扩展至内部、且40%<腐烂面积占比≤50%,支须根腐烂;4级,腐烂已扩展至内部、且50%<腐烂面积占比≤70%,支须根腐烂脱落;5级,腐烂已扩展至内部、且腐烂面积占比>70%直至整个块根完全腐烂,支须根腐烂。本标准于2016~2017年连续2年被用于评价土壤处理防控三七根腐病害的发生危害和防治效果,结果显示,该标准可以较好地对不同土壤处理的防病效果进行量化和评估,且与传统分级标准相比,其评价结果更优。 相似文献
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小麦条锈病Puccinia striiformis West.严重度分级标准,目前在我国应用最多的是《农作物主要病虫测报办法》(以下简称《办法》)中的分级标准(分5%以下、5%、10%、25%、40%、65%、80%和100%8级)。这个分级标准,级别较多级距较乱,难于记忆。商鸿生等(1990)虽然作了改进(分级标准为1%、5%、10%、20%、40%、60%、80%和100%8级),但笔者认为这个标准仍较麻烦,对于在基层仍不适用。因此,笔者根据多年的实践经验,制定出既能反映真实情况,又简便易行的新的分级标准(定名为简易分级标准),即5%以下、10—20%、30—40%、50—80%、80—100%5级(参见分级标准图)。 相似文献
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BACKGROUND: The present study describes the quantitative changes in herbicide use during the specific observation periods in the Wheat Self-sufficiency Project in Iran from 1994 to 2004 and the associated changes in herbicide risk, area and yield in this context. A risk index, the environmental impact quotient (EIQ), was used to estimate the environmental impacts (EIs) of herbicides applied to wheat agroecosystems. RESULTS: The results suggest that, during this period, the overall risk posed by the herbicides applied to wheat agroecosystems increased substantially, as evidenced by a 71% increase in herbicide usage (weight of pesticide applied) and a 62.2% increase in EI rating, in spite of an 8.2% decrease in overall EIQ rating and an 89.2% decrease in mean application rate. Furthermore, a 0.57% increase in the area and a 23.6% and 22.7% increase in irrigated and rainfed yields, respectively, were observed. The results also indicate that the EIQ(FUR) of two herbicides, dichlorprop-P/mecoprop-P/MCPA and difenzoquat, is much higher than that of other herbicides, and they could be qualified as high-risk herbicides. CONCLUSION: As a whole, an increase in herbicide usage (weight of pesticide applied) was an important factor on herbicide environmental impact boost. However, this increase has not led to a similar increase in wheat yield, which could be attributed in part to the negative impact of high herbicide consumption in wheat fields and subsequent threat to the long-term sustainability of these agroecosystems. 相似文献
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Field monitoring and scenario-based modelling were used to assess exposure of small ditches in the UK to the herbicide sulfosulfuron following transport via field drains. A site in central England on a high pH, clay soil was treated with sulfosulfuron, and concentrations were monitored in the single drain outfall and in the receiving ditch 1 km downstream. Drainflow in the nine months following application totalled 283 mm. Pesticide lost in the first 12.5 mm of flow was 99% of the total loading to drains (0.5% of applied). Significant dilution was observed in the receiving ditch and quantifiable residues were only detected in one sample (0.06 microg litre(-1)). The MACRO model was evaluated against the field data with minimal calibration. The parameterisation over-estimated the importance of macropore flow at the site. As a consequence, the maximum concentration in drainflow (2.3 microg litre(-1)) and the total loading to drains (0.76 g) were over-estimated by factors of 2.4 and 5, respectively. MACRO was then used to simulate long-term fate of the herbicide for each of 20 environmental scenarios. Resulting estimates for concentrations of sulfosulfuron in a receiving ditch were weighted according to the prevalence of each scenario to produce a probability distribution of daily exposure. 相似文献
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我国有占世界19%的人口,但仅有占世界9%的耕地,因此保证国家粮食安全是头等大事。在确保生态环境安全的前提下,如何增加作物产量和保障农产品质量安全始终是我国农业快速发展面临的一大挑战。在高效、负责、透明的政府能力建设中,我国农业的绿色发展和高质量发展战略,我国农药管理的法制建设、市场监管、食品安全、环境监测、有害生物治理、应用技术服务及推广等都取得了显著进步。到2021年底,我国已经登记了740多个农药有效成分,41 433个农药产品。2021年,全国1 705家农药定点企业,共生产了化学农药原药249.8万t。不仅满足了国内有害生物防控的实际需要,还出口180多个国家和地区,农药出口额达到234亿美金。我国还有的10个高毒农药品种,已经控制在1.3%以下,且安排在未来5年内会陆续退市。本文还分析梳理了今后我国农药管理发展所面临的挑战。 相似文献
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为了更好地评估农药使用对人类健康和生态环境的综合影响,利用可方便获取的农药有效成分特性数据资源,在综合考虑健康及环境影响评估的定量化、参数的代表性、测试方法的标准化、现有可获取数据的权威性和完整性,以及评估核算过程的便利性等要求基础上,构建了药迹模型及其指标体系。采用所建立的药迹模型可计算得到表征各种农药对健康和环境影响力的药迹指数,再结合农药用量数据,即可对不同时空尺度下农药使用产生的健康和环境影响进行定量化的核算和比较。通过该模型对70种代表性农药进行核算,结果表明,药迹指数为0.002~111.348 PTU/kg,单次用量药迹为0.001~41.412 PTU/hm2,不同农药品种间差距很大。该药迹模型具有广泛的应用前景,如药迹指数可用于农药危害性分类,药迹核算可用于农药减施成效评估,药迹限量可用于农药施用限量标准制定等。 相似文献
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谢璇;刘芫汐;周婷婷;金红宇;段丽芳;杨华;王莹;魏锋 《农药学学报》2025,27(2):196-206
为推动中药材中农药残留限量标准的制定及其监管体系建设,本文系统梳理了近年来中药材中农药残留风险评估方法的研究进展,重点分析了相关参数的选择与应用,特别探讨了在中药材多农药残留背景下累积风险评估方法的应用与挑战,并立足我国中药材中农药残留风险评估现状提出建议,以期为风险评估方法的完善提供参考。 相似文献
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Peterson RK 《Pest management science》2006,62(1):46-56
Environmental risk assessment of pesticides and other chemicals often uses the Risk Quotient (RQ) method to characterize risk quantitatively. An RQ is calculated by dividing an environmental exposure value by a toxicity end-point value. Tier 1 RQs, which are characterized by highly conservative toxicity and exposure assumptions, are used primarily for screening out negligible risks in regulatory decision making. It has been argued that the tier 1 RQ approach is valuable for making direct comparisons of quantitative risk between pesticides. However, an outstanding question is whether relative risks among pesticides would change if refinements of exposure are incorporated into the RQ calculations. This study tested that hypothesis. Aquatic ecological risk assessments were conducted for 12 herbicide and 12 insecticide active ingredients used on agricultural crops in the USA. The pesticides were chosen because surface-water monitoring data for them were available as part of the United States Geological Survey's National Water-Quality Assessment Program (NAWQA). Ecological receptors and effects evaluated were aquatic non-vascular plants (acute risk), aquatic vertebrates (acute risk) and aquatic invertebrates (acute risk) for the herbicides and aquatic vertebrates (acute and chronic risk) and aquatic invertebrates (acute and chronic risk) for the insecticides. The data indicate that there were significant statistical correlations between numerical rankings of tier 1 RQs and RQs using refined environmental exposures. The results support the hypothesis that numerical ranking of RQs for the purpose of comparing potential ecological risks is a valid approach because the rankings are significantly correlated regardless of the degree of exposure refinement. 相似文献
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生态旅游系统管理与生态风险分析 总被引:1,自引:0,他引:1
尚天成 《干旱区资源与环境》2008,22(5):91-94
在分析生态旅游系统内涵、指导思想和管理原则的基础上,将生态风险分析理论与方法引入生态旅游系统管理中,阐述生态旅游系统中生态风险分析的含义、内容、程序以及生态风险分析的方法,分析生态旅游系统中生态风险管理与生态风险分析的关系,探讨生态风险分析在生态旅游系统管理中的应用。 相似文献