气相色谱法测定禽蛋中有机氯农药和多氯联苯残留量

建立了同时测定禽蛋中14种有机氯农药(OCPs)和7种多氯联苯(PCBs)的气相色谱法。样品用乙腈超声提取,浓硫酸净化,气相色谱法测定,外标法定量。21种待测化合物在5～200μg/L时线性关系良好,方法定量限为0.3～0.7μg/kg,在5、20、100μg/kg三个加标水平下,鸡蛋空白样品的平均加标回收率为75.1%～103.8%,相对标准偏差为1.41%～6.64%。本法简便、快速、准确、成本低廉,适用于禽蛋中多种有机氯农药和多氯联苯的快速筛查。     

Long-established and emerging pesticide poisoning in horses

Poisoning is a frequent problem in domestic animals. Horses are the third most commonly affected species and pesticides are one of the main causes of toxicosis. Here within are reviewed the most frequent toxicoses where it emerges that the main causes are misuse and accidental exposure. Rodenticides, acetylcholinesterase insecticides followed by herbicides are the main cause of toxicosis and effects of emerging chemicals are being reported. Metaldehyde is still a problem, together with methiocarb. No information has been reported on poisoning with pesticide mixtures.     

云南省森林昆虫病毒资源及其开发研究

在回顾我国,我省昆虫病毒研究历史的基础上,对云南省森林昆虫病毒资源,松毛虫病毒资源及其生物防治的研究,应用,病毒杀虫剂的产业化与开发利用前景等方面作了综合详尽的分析,就存在问题和解决途径也作了有益的讨论。     

拟除虫菊酯和有机磷农药对三种扇贝稚贝的急性毒性效应

采用静水实验法测定拟除虫菊酯类和有机磷类农药对三种扇贝稚贝的急性毒性效应.结果表明:联苯菊酯对海湾扇贝、栉孔扇贝和虾夷扇贝稚贝24 h的LC50的分别为1.460、1.662和2.909 mg/L;辛琉磷对海湾扇贝、栉孔扇贝和虾夷扇贝稚贝24 h的LC50的分别44.598、182.167和39.334 μg/L;马拉...     

Aerial applications of pesticides in the United Kingdom: 1978 to 1998

The aerial application of pesticides increased rapidly following the end of the Second World War, as, along with the development of a wider range of synthetic pesticides, more planes and pilots became available. It also became clear that new and previously inaccessible areas could be sprayed from the air. By the 1980s there were around 100 planes in the United Kingdom (UK) capable of spraying pesticides. However, increasing environmental pressure brought about the introduction of tougher legislation to control pesticide usage. The Food and Environment Protection Act 1985 and the Control of Pesticides Regulations 1986 (as amended) introduced tight controls over the application of pesticides from the air. Aerial application of pesticides has been monitored each year by the UK Ministry of Agriculture, Fisheries and Food (MAFF) since 1978, during which time the area treated has decreased significantly. This has been partly as a result of changes in legislation but also due to technological improvements in conventional crop‐protection methods. The area treated from the air in the UK has never risen above 2.5% of the area treated from the ground and in 1998 had fallen to less than 0.04% of the total area treated with pesticides. It is likely that this figure will continue to fall in the future. By 1998, the only pesticides to be sprayed from the air comprised fungicides, herbicides and insecticides. As a group, herbicides comprised the greatest area of treatment and the only target to show an increase in area treated in recent years has been bracken (Pteridium aquilinum (L) Kuhn). © Crown copyright 2000. Reproduced with the permission of Her Majesty's Stationery Office.     

Economic use of pesticides in the Ukraine

The total value of agricultural production in the Ukraine amounts to $30 billion, equivalent to 30% of the Gross Domestic Product (GDP). The annual cost of pesticide inputs is estimated to be $200–225 million. Herbicides and insecticides account for approximately 50% and 30% of pesticide use, respectively. The government has introduced a National Programme for the development of agricultural production over the next five to eight years. The programme envisages an expansion in agricultural production and pesticide use and a continuation of the move towards a free‐market economy. Improvements in crop yield and quality will benefit both the individual grower and the national economy. In the transition to the free‐market economy, growers require a clear understanding of present pesticide technology and crop production systems. A major change of attitude is required by all those people involved in providing and using pesticides to ensure that they are used both economically and safely. To address this issue, a Regional Academic Programme (REAP), involving Writtle College and Bila Tserkva State Agrarian University, has been initiated. © 2000 Society of Chemical Industry     

Availability of pesticide-treated seed on arable fields

A study of the availability of pesticide-treated seed on arable fields was performed. The research was carried out in three different areas of The Netherlands (soil types ranging between sand and heavy clay) and included the following topics: drilling techniques, soil conditions, location on the field and spillage. The results show that there is a large variation among the various crops in the percentage of seed remaining on the soil surface. This is mainly caused by differences in drilling techniques and soil conditions. The percentage of surface seeds after standard drilling is approximately four times higher than after precision drilling. The best correlation for the impact of soil conditions was found for the overall measure of clod weight. Large differences in seed densities (factor of 3.5) were found between the headland and the field centre. Spillage occured in most crops investigated, with an average of two spills per field. Based on the field data it is recommended to use in the current risk assessment for birds and mammals the following percentages of seed remaining on the soil surface: 0.5% for precision drilling, 3.3% for standard drilling in spring and 9.2% for standard drilling in autumn.     

The effects of pesticides on species of non-target Heteroptera inhabiting cereal fields in southern England

The effects of pesticides on beneficial predatory arthropods have been widely studied; this paper however deals with their effects on Heteroptera, an important beneficial insect group and food source for farmland birds. Field trials were used to evaluate pesticide effects under realistic conditions of application on a commercial arable farm and compared with previously published laboratory findings. Fungicides were found to produce very low levels of mortality, not significantly different from control treatments. Aphicides varied in their impact, producing non-significant to highly significant mortality levels. The likely ecological impact of pesticides on various heteropteran groups found within the field and field boundary is discussed. © 1997 SCI.     

基于线性模型的管路内农药混合均匀性评价方法

针对混合试验图像所得均匀性指数计算结果难以直接匹配于被广泛认可的数值仿真参考值的问题,本文基于线性模型方法,将混合试验图像处理与数值仿真结果进行映射,在黏性水溶性农药与水在长直混合管内进行在线混合的试验条件下构建对应的线性预测模型,并采用射流混药器在线混合图像及仿真结果对上述模型进行检验。研究结果表明：不同图像方法(灰度直方图二阶矩(HSM)、改进面积加权法(OAU)、主成分分析法(PCA))对应最优线性拟合阶数不同,采用单独图像方法构建模型时最优阶次为4,决定系数R2高于0.95,采用2种图像方法组合和3种图像方法组合时最优阶次可分别降至3阶和2阶,R2则接近或高于0.98;载流流量Q为800~2000mL/min、混合比P为0.01~0.10条件下,基于HSM、OAU、PCA和线性模型,可实现实际混药器均匀性预测,所有模型预测误差均小于0.05,且采用一元和二元线性模型使得平均预测误差分别降低84.1%和79.8%,不同算法间预测结果极差分别降低31.6%和78.0%;采用基于PCA或OAU算法的一元模型进行预测时误差可控制在0.03以内,其精度高于不同算法组合预测的结果;采用基于HSM-PCA等算法组合的二元模型误差虽稍高于0.03,但也可避免单一图像指标计算不准确带来的预测风险。通过构建图像处理-数值仿真之间的映射关系,可为基于图像处理进行农药在线混合均匀性评估提供更加可行和合理的方法。     

九龙江流域农田土壤有机氯农药残留污染特征

为了探究有机氯农药(Organochlorine Pesticides,OCPs)在农田土壤中的分布及残留污染特征,2014-2016年利用ASE萃取技术,使用GCPMS方法测定了九龙江流域农田(水田、果园、菜地)土壤主要OCPs,同时采用相关分析和主成分分析方法,研究九龙江流域农田土壤OCPs残留的影响因素及其污染特征。结果表明,该流域农田土壤中残留的有机氯农药主要是六六六(HCHs)、滴滴涕(DDTs)和六氯苯(HCB),其中HCHs是土壤残留有机氯农药的主要成分;氯丹(TC+CC)、九氯(TN+CN)、硫丹(α-End+β-End)残留量较低,是普遍存在的一类持久性有机污染物。有机氯农药均随土层深度的增加而急剧降低,并且随深度的增加其降低幅度逐渐增加,垂直分布表现出明显的"表聚性",相同土层OCPs含量基本表现为水田果园菜地。DDTs含量平均值顺序基本表现为o,p′-DDTp,p′-DDTp,p′-DDD;其中o,p′-DDT是DDT类污染物的主体物质。HCH含量基本表现为β-HCHα-HCHγ-HCHδ-HCH;其中β-HCH和α-HCH占比相对较高,具有较高的潜在危害性;而α-HCH/γ-HCH比值小于1,存在较多的γ-HCH残留。主成分分析显示,α-HCH、β-HCH、γ-HCH和δ-HCH在第一主成分上有较高载荷;DDTs类物质在第二主成分上有较高载荷;TC和CC、α-End和β-End、TN和CN在第三主成分上有较高载荷。Pearson相关分析表明,TOC与HCHs、HCB、OCPs呈极显著正相关(P0.01),与α-End和β-End呈显著正相关(P0.05),与DDTs相关性不显著(P0.05),说明九龙江流域农田土壤HCHs、HCB含量在很大程度上受TOC影响,HCHs与HCB、DDTs,HCB、DDTs与九氯(TN+CN)类农药的分布机制和输入来源可能一致,在决定有机氯农药含量和分布上起着重要的作用。