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1.
我国微生物农药的应用现状   总被引:9,自引:0,他引:9  
对微生物农药的概念、种类及其作用机理进行了综述,其中重点介绍了微生物农药的分类,同时对我国目前使用的几类微生物农药的研究应用状况进行了阐述,并提出微生物农药现存的问题及其解决方案,指出微生物农药的发展前景是乐观的。  相似文献   

2.
贵州省农村农药使用情况调查及水源地污染现状研究   总被引:1,自引:0,他引:1  
介绍了国内饮用水源地农药污染研究现状,并对贵州省9个行政区划内的27个县乡,总计200多家农药销售市场的农药销售状况及农户的农药使用情况进行调查。采用气相色谱/质谱联用技术(GC/MS),对贵阳市红枫湖、阿哈水库、百花湖3个城市饮用水源地的15个监测断面中的13种有机农药残留进行检测,结果检出α-HCH、β-HCH、γ-HCH、δ-HCH、三唑酮、腐霉利6种农药。其中,HCHs主要来自于环境残留及农药林丹的使用。  相似文献   

3.
文章根据我国农药生产和使用的特点,结合环境污染事故中常见的农药、保障农产品安全需控制的农药残留等,阐述了我国环境中需重点控制的农药残留种类,并对其监测方法和控制标准进行了综述,旨在为农药污染事件中快速判断污染类别、科学确定监测方法、及时处置污染提供技术保障。  相似文献   

4.
基于荧光素酶发光体系测试饮用水中农药的综合毒性   总被引:1,自引:0,他引:1  
利用农药对荧光素酶催化的发光反应具有非常显著的抑制作用,对甲拌磷、乐果、毒死蜱、百草枯等4种农药分别进行单一毒性和等比混合法联合毒性测试,建立了一种快速检测饮用水中农药综合毒性的生物学方法。试验结果表明,单一农药乐果、甲拌磷、百草枯和毒死蜱的EC50值分别为7.56 mg/L、12.7 mg/L、19.0 mg/L和65.3 mg/L,毒性强弱顺序为乐果甲拌磷百草枯毒死蜱,相关系数≥0.995;将4种农药以等比方式配制成两两混合液后,当质量浓度为20.0 mg/L~100 mg/L时,除百草枯与毒死蜱表现为毒性协同外,其他两两混合农药的毒性以拮抗作用为主。  相似文献   

5.
城市污水处理厂水样中菊酯类农药残留分析   总被引:9,自引:0,他引:9  
建立了基于C18固相萃取柱和气相色谱/电子捕获(GC/ECD)分析水体中环境激素类物质——菊酯类农药的分析方法,并对方法的回收率、灵敏度进行了评价,同时分析了北京市高碑店、北小河两个城市污水处理厂进水与出水中菊酯类农药的浓度,研究发现在其废水中存在联苯菊酯、氯氰菊酯、氰戊菊酯和溴氰菊酯,浓度在0.013~0.920μg/L之间。结果表明,曝气活性污泥法对菊酯类农药的去除效果较好。方法对菊酯类农药的回收率达到67.7%~96.2%,方法检测限为0.010~0.015μg/L。  相似文献   

6.
中空纤维膜萃取-气相色谱法测定水中有机氯农药   总被引:1,自引:1,他引:0       下载免费PDF全文
提出了中空纤维膜萃取-气相色谱法测定水中有机氯农药的方法。首先研究了8种有机氯农药的线性范围,然后测定了中空纤维膜萃取对水中有机氯农药的回收率,最后用中空纤维膜萃取-气相色谱法对实际水样进行检测。结果表明,8种有机氯农药在0.5~10μg/L范围内具有良好的线性关系,中空纤维膜萃取法对水中8种有机氯农药的富集倍数为389~464,回收率为77%~92%,可以满足分析要求。  相似文献   

7.
北京工业废水和城市污水中有机氯农药残留分析   总被引:2,自引:0,他引:2  
建立了基于HLB固相萃取柱和气相色谱-电子捕获(GC-ECD)测定水体中有机氯农药的方法,并对方法的回收率、灵敏度进行了评价,同时分析了北京市七类典型污染点源50个采样点位有机氯农药的浓度,检测到的有机氯农药包括γ-六六六、β-六六六、4,4’-滴滴涕、α-六六六、δ-六六六、硫丹Ⅰ、4,4’-滴滴伊、艾氏剂和异狄氏剂,它们的检出率分别为90%、60%、50%、46%、26%、8%、6%、2%和2%。主要有机氯农药污染残留为γ-六六六、β-六六六和4,4’-滴滴涕。检出有机氯农药浓度范围是0.20~76.40ng/L。方法对有机氯农药的回收率达到60.93%~141.50%,方法检测限为0.27~2.90ng/L。  相似文献   

8.
通过对上海市高尔夫球场农药使用情况的详细调查,结果显示:当前高尔夫球场使用的农药主要包括3大类43种,包含杀菌剂20种、杀虫剂14种和除草剂9种,种类组成及施用量均以杀菌剂为主;施用农药以微毒、低毒农药为主(占69.8%),高毒农药主要为杀虫剂;不同球场农药使用种类、强度和频次等存在较大差异,主要与球场规模、草坪种类及管理水平等有关;当前高尔夫球场农药使用中仍存在农药施用强度较高,农药施用种类较多,品种结构仍有待优化等问题。  相似文献   

9.
酶抑制法检测蔬菜中的有机磷农药   总被引:5,自引:0,他引:5  
对新型酶抑制检测蔬菜中有机磷农药残留量的方法进行了研究,介绍了胆碱酯酶的提取、纯化方法,以及用粗酶和纯酶检测蔬菜中有机磷农药残留量的测定效果,确定了最佳实验条件。对样品的预处理方法进行了改进,得出该法的检测限为1mg/L,对甲基对硫磷等几种常用农药的加标回收率为90.4%~112%,相对标准偏差为1.06%~9.83%,表明三项评价指标均符合全国农药残留科研协作组对农药残留分析方法的基本要求。  相似文献   

10.
南四湖表层沉积物中有机氯农药的含量及分布特征   总被引:3,自引:0,他引:3  
利用气相色谱-电子俘获检测(GC-ECD)方法对南四湖表层沉积物中13种有机氯农药进行了分析测定。每个采样点均检出了有机氯农药,与世界其它类似水体比较,南四湖表层沉积物中的有机氯农药处于低水平含量,属于低生态风险水平。多数点位有机氯农药均是由于历史上使用造成的,但不排除个别点位存在新的污染源。  相似文献   

11.
Animal hair is a good biomonitoring tool for heavy metals assessment and reflects the content of heavy metals in the forage and soil. Heavy metals Fe, Mn, Co and Ni as well as toxic metals Cd and Pb were determined in goat, sheep and camel hair, forage and soil collected from four different environmental urban and rural regions. These regions are Aswan city farms, Allaqi desert pasture, Kalabsha farms and Halaiub desert pasture at far south of Egypt. The results reveal that sheep hair contains the highest levels of Fe and Mn (879 and 55 μg/g, respectively), camel hair contains the highest Pb, whereas for goat Cd and Ni were the highest. Heavy metal concentrations in the studied hair reflect the presence of these metals in the surrounding forage and soil and vary from one area to another, and give knowledge of pollution in the area. Correlation statistics analysis and cluster analysis show a good and significant value between metals in hair and plants.  相似文献   

12.
An important research area in life sciences is devoted to modeling, prediction, and dynamics of gene-expression patterns. As clearly understood in these days, this enterprise cannot become satisfactory without acknowledging the role of the environment. To a representation of past, present, and most likely future states, we also encounter measurement errors and uncertainties. This paper surveys and improves recent advances in understanding the foundations and interdisciplinary implications of the newly introduced gene–environment networks, and it integrates the important theme of carbon dioxide emission reduction into the networks and dynamics. We also introduce some operational and managerial issues of practical working and decision making, expressed in terms of sliding windows, quadrants (modules) of parametric effects, and navigating (controlling) between such effects and directing them. Given data from DNA microarray experiments and environmental records, we extract nonlinear ordinary differential equations that contain parameters that have to be determined. For this, we employ modern (Chebychevian) approximation and (generalized semi-infinite) optimization. After this is provided, time- discretized dynamical systems are studied. A combinatorial algorithm with polyhedra sequences allows to detect the region of parametric stability. Finally, we analyze the topological landscape of gene–environment networks with its structural (in)stability. By embedding as a module and investigating CO2 emission control and figuring out game theoretical aspects, we conclude. This pioneering work is theoretically elaborated, practically devoted to health care, medicine, education, living conditions, and environmental protection, and it invites the readers to future research.   相似文献   

13.
We developed an assessment and monitoring plan for birds in connection with the exploration and potential development of a large natural gas field in the Lower Urubamba drainage of Peru, a project of Shell Prospecting and Development Peru (SPDP). Our objectives were to: (1) inventory the birds in the area, including information on habitat use and abundance, and (2) devise long-term monitoring protocols for birds. We sampled birds through a combination of visual and auditory surveys and mist-netting at 4 well sites and 3 sites along the Urubamba and Camisea rivers. We recorded 420 speciesduring 135 days of field work. We consider the highest prioritiesfor a future monitoring program to be: (1) establish whether edge effects are occurring at well sites, along roads and alongthe planned pipeline route and determine the significance and extent of these effects and (2) assess the impact of increased human access to the area on game and other exploited species. The remoteness of the area, its rugged terrain and dense vegetation and the lack of trained personnel limit the choice of survey and monitoring methods. We recommend use of mist-netting and transects for monitoring edge effects and useof transects for monitoring game and other exploited species.  相似文献   

14.
This paper presents the chemical speciation and retention behavior of chromium (Cr), nickel (Ni), and cadmium (Cd) prior to and after the electrokinetic remediation in glacial till soil. The speciation of the metals was predicted using the chemical speciation program MINEQL+. The simulations were performed for single-contaminant with only Cr(VI) or Ni, and multi-contaminants consisting of: (1) Cr(VI), Ni, and Cd; (2) Cr(III), Ni and Cd; (3) Cr(VI), Cr(III), Ni and Cd; (4) Cr(VI), Ni, and Cd with reducing agents; and (5) Cr(III), Ni, and Cd with oxidizing agent (Mn). The results showed that the speciation and distribution of cationic metals [Ni, Cd, and Cr(III)] in glacial till soil remain unaffected or slightly affected during electrokinetics. This is attributed to the high pH buffering capacity of the glacial till, leading the metals to precipitate in the soil prior to and after electrokinetics. This study showed that during electrokinetics, Cr(VI) existed as anionic complex and migrated towards the anode and the migration is maximum in case of a single-contaminant system. The study also showed that near the anode in the absence of any reducing and oxidizing agent, Cr(VI) mostly adsorbed, and some of Cr(VI) reduced to Cr(III) and migrated towards the cathode and finally precipitated due to high pH conditions. Ni and Cd remain adsorbed or precipitated due to the high pH conditions throughout the soil. Among the reducing agents, the sulfide had significant effect on the migration of metals compared to ferrous ions. While in the presence of oxidizing agent (Mn), no noticeable Cr(VI) was found in the soil sample indicating the reduction of Cr(VI) to Cr(III) and the predominance of reducing conditions due to the presence of naturally occurring iron in the glacial till soil. Overall, this study provides a reasonable explanation of the speciation and distribution of chromium, nickel and cadmium during the electrokinetic remediation of glacial till soil.  相似文献   

15.
Monitoring of impacts of floods in river valleys of dryland regions has become important with the onset and threats of desertification and is likely to become even more vital with predictions of increased effects of climate and land use change. It is also needed in order to conform to requirements of the EU Water Framework Directive. Monitoring in such regions sets particular challenges. This paper explains a system of low-cost monitoring of changes in morphology, vegetation and sediment cover in channels and valley floors of ephemerally flowing streams. It has been applied in SE Spain for 10 years and has proved very effective. In particular, the use of simple crest-stage recorders for measuring flow height and the use of real-time differential GPS for rapid and accurate survey and for relocating points have proved very valuable. Part of the monitoring is focused on the interaction of plants and channel processes. Small changes in and around vegetation associated with flow events have been detected by a combination of quadrat surveys and cross-profiling of the channel. A range of flow events has been measured over the period of monitoring, demonstrating their differing effects and the varying sensitivity and responsiveness of different sites. The sporadic occurrence of flood events in such an environment means that a strategy of monitoring several sites and of continuation over many years has great benefits.  相似文献   

16.
Anthropogenic inputs of nitrogen (N), phosphorus (P) and oxygen-consuming material to aquatic ecosystems can change nutrient dynamics, deplete oxygen, and change abundance and diversity of aquatic plants and animals. The Northern Rivers Ecosystem Initiative required a research and assessment program to establish the contribution of pulp mill and sewage discharges to eutrophication and depressions in dissolved oxygen (DO) in the Athabasca and Wapiti rivers of northern Alberta, Canada and examine the adequacy of existing guidelines for protecting these systems. Analysis of long-term data showed that total N (TN) and total P (TP) concentrations in exposed river reaches exceeded concentrations in reference reaches by ≤ 2 times for the Athabasca River, and by 9.6 (TP) and 2.6 (TN) times for the Wapiti River. Results from nutrient limitation experiments conducted in situ and in mesocosms showed that benthic algal production was nutrient sufficient downstream of pulp mill discharges but constrained in upper river reaches by insufficient P (Athabasca River) or N + P (Wapiti River). Dissolved oxygen (DO) concentrations in both rivers declined during winter such that median concentrations in the Athabasca River 945 km downstream of the headwaters were approximately 8 mg L−1 in mid-February. Although water column DO rarely approached the guideline of 6.5 mg L−1, DO studies undertaken in the Wapiti River showed that pore water DO often failed to meet this guideline and could not be predicted from water column DO. Results from this integrated program of monitoring and experimentation have improved understanding of the interactions between nutrients, DO and aquatic ecosystem productivity and resulted in recommendations for revisions to nutrient and DO guidelines for these northern rivers.The Canadian Crown reserves the right to retain a non-exclusive, royalty free licence in and to any copyright.  相似文献   

17.
The Canadian Arctic is undergoing considerable social and environmental change. Anthropogenic stressors on this sensitive environment include climate change, contaminants, resource extraction, tourism and increasing human populations. The Northern Ecosystem Initiative (NEI) is a program aimed at supporting the sustainability of northern communities, and at improving our understanding of how northern ecosystems respond to these environmental stressors. A key element of the NEI is to establish partnerships between all levels of government, non-governmental environmental agencies, and northern residents. The NEI is an important source of financial support critical for social and environmental scientists as well as northern residents and their community and regional organizations. Initiated in 1998, the NEI has supported numerous northern scientific and capacity-building projects, and has evaluated the information gained from this work to refine and focus its future support to address key information gaps and northern needs.  相似文献   

18.
The role of relationships between regulators and consultants engaged in environmental impact assessment (EIA) is explored. A Partnering Agreement between Western Australian regulators and consultants gave rise to a survey and interviews with representatives of these EIA practitioners to understand levels of cooperation between them and ways to improve EIA practice locally. A mixture of quantitative and qualitative responses are presented with an emphasis on practitioner comments reproduced in their own words and ‘voice’. The results suggest that while relationships are strained because of staff resources and levels of expertise brought about by a major resource boom in recent years, there is a great desire for cooperation and collaboration. Greater clarification and understanding of each stakeholder's purpose and role in the EIA process along with opportunities for EIA practitioners to interact, communicate and socialise are identified as positive ways forward. The value of establishing the relatively simple Partnering Agreement approach is demonstrated and is put forward as something that practitioners internationally might equally benefit from as a means of improving the effectiveness of EIA practice.  相似文献   

19.
Criteria and Indicators of Sustainable Forest Management   总被引:2,自引:0,他引:2  
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20.
Metals and radionuclide levels in marine birds of the Aleutians are of interest because they are part of subsistence diets of the Aleut people, and can also serve as indicators of marine pollution. We examined geographic and species-specific variations in concentrations of radionuclides in birds and their eggs from Amchitka, the site of underground nuclear tests from 1965 to 1971, and Kiska Islands (a reference site) in the Aleutians, and the levels of lead, mercury and cadmium in eggs. In 2004 we collected common eiders (Somateria mollissima), tufted puffins (Fratercula cirrhata), pigeon guillemot (Cepphus columba) and glaucous-winged gulls (Larus glaucescens) from Amchitka and Kiska, and eggs from eiders and gulls from the two island. We also collected one runt bald eagle (Haliaeetus leucocephalus) chick from both Amchitka and Kiska Islands. For most species, the levels of radionuclide isotopes were below the minimum detectable activity levels (MDA). Out of 74 cesium-137 analyses, only one composite (gulls) was above the MDA, and out of 14 composites tested for plutonium (Pu-239, 240), only one exceeded the MDA (a guillemots). Three composites out of 14 tested had detectable uranium-238. In all cases, the levels were low and close to the MDAs, and were below those reported for other seabirds. There were significant interspecific differences in metal levels in eggs: gulls had significantly higher levels of cadmium and mercury than the eiders, and eiders had higher levels of lead than gulls. There were few significant differences as a function of island, but eiders had significantly higher levels of cadmium in eggs from Kiska, and gulls had significantly higher levels of mercury on Kiska. The levels of cadmium and mercury in eggs of eiders and gulls from this study were above the median for cadmium and mercury from studies in the literature. The levels of mercury in eggs are within the range known to affect avian predators, but seabirds seem less vulnerable to mercury than other birds. However, the levels of mercury are within the action levels for humans, suggesting some cause for concern if subsistence Aleuts eat a large quantity of eggs.  相似文献   

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