Loss of pesticides from agricultural fields in SE Norway--runoff through surface and drainage water

Loss of two pesticides with different mobility characteristics, bentazone (Koc approximately 34) and propiconazole (Koc approximately 1800), were studied at three agricultural fields (Askim, Bj?rnebekk and Syverud) in SE Norway. A conservative tracer (Br) was used to follow the flow of water. The loss of pesticides varied among the fields, depending on hydrological characteristics and soil properties. The loss of pesticides was higher from two artificially levelled silty clay loam soils with poor aggregate stability (Askim and Bj?rnebekk) compared to a loam/silt loam soil with increased content of organic carbon and better aggregate stability (Syverud). The total accumulated loss was <0.5% from all fields. The highest pesticide concentrations were measured at the first runoff episode after application for both the mobile (bentazone) and less mobile pesticide (propiconazole) in the surface runoff. In the drainage water, the peak for the less mobile pesticide coincided with the Br tracer, while the peak for mobile pesticide appeared earlier than the Br tracer. Rapid movement of water, particles and pesticides through soils indicate flow through macropores. Larger proportions (in percent of total applied) of both the mobile and the strongly sorbed pesticides were lost through the drainage as compared to the loss through surface runoff at Askim. Here, it is suggested that macropore flow contribute to the increased loss of pesticides through the drainage. At Syverud, high infiltration capacity reduces the amount of water available for surface runoff, and somewhat higher loss of the mobile pesticide was registered in the drainage compared to the surface runoff. For the strongly sorbed pesticide, however, propiconazole was neither detected in surface nor in drainage water at Syverud. Generally, there was a higher percentage loss of the mobile compared to the strongly sorbed pesticide in both surface and drainage water, which is in agreement with the pesticides mobility characteristics in soil. An exception was, however, the erodible soil Bj?rnebekk, where a higher fraction of propiconazole was lost in the surface runoff compared to bentazone. Large amounts of sediment transport from the Bj?rnebekk field probably contributed to enhanced transport of the strongly sorbed pesticide.     

基于CVM方法分析牧民对禁牧政策的受偿意愿——以锡林郭勒草原为例

确定居民对生态措施实施的受偿意愿,对目前迫切需要的生态补偿政策制定以及生态恢复和保护的有效性具有重要的现实意义。选用锡林郭勒草原为案例区域,通过入户调查及在那达慕大会集中调查相结合的方式,调查锡林郭勒草原地区牧民对禁牧措施的态度和受偿意愿。分析结果显示:53%的牧民愿意参加禁牧,而不愿意参加禁牧主要是由于补偿标准不合理引起的。计量经济学模型分析表明,牧民对禁牧的支持态度与牧民的收入和草地面积呈正相关,与养羊数量呈负相关。牧民的受偿意愿由牧民养羊数量、受教育年限、草地现状以及对禁牧政策的支持程度决定。根据意愿调查法初步估算锡林郭勒草原地区禁牧措施实施后牧民的补偿意愿,牧民家庭对禁牧政策的平均受偿意愿为每年每户2.7717万元,人均受偿意愿为8399元,平均每1hm2草地受偿意愿为85.95元。     

上海城市绿地系统构筑初探

本文从剖析上海城市绿地存在问题入手，结合城市规划配套发展原则，走生态城市大园林之路，探讨了绿地系统构筑的指导思想和原则，研究并提出了城市绿地系统的构筑的四大子系统体系。     

Hydroquinones from defensive secretion of a giant Pacific millipede, <Emphasis Type="Italic">Acladocricus setigerus</Emphasis> (Diplopoda: Spirobolida)

Summary. The presence of considerable quantities of hydroquinones including hydroquinone, 2-methylhydroquinone, 2,3- dimethoxyhydroquinone, 2-methoxy-3-methylhydroquinone, and 2,3-dimethoxy-5-methylhydroquinone renders the defensive secretion of Acladocricus setigerus (Silvestri, 1897) significantly different from that of other quinone-producing millipedes. In addition, two hitherto undescribed compounds, namely, 2,3-dimethoxy-5-methylhydroquinone and 2-methyl-3,4-methylenedioxyphenol, were characterized from the defensive secretion. However, it is uncertain if the latter compound is formed after the release of the secretion. The two major compounds, 2-methyl-1,4-benzoquinone and 2-methoxy-3-methyl-1,4-benzoquinone, constitute about 75% of the defensive fluid. Furthermore, hydrocarbons, which are typically present in the secretions of most other arthropods that use benzoquinones as repellents, are notably absent in the secretion of A. setigerus.     

Synthesis, Characterization, and Hydrolytic Degradation of Copolymers of 2-Methylene-1,3-dioxepane with Ethylene and with Styrene

2-Methylene-1,3-dioxepane (MDP) was copolymerized with ethylene (E) at a pressure of approximately 1000 psi and a temperature of approximately 70°C with AIBN as the free radical initiator. The copolymers obtained, poly(MDP-co-E), were characterized by elemental analysis, IR, ¹H-NMR and ¹³C-NMR spectroscopy, DSC, and GPC. The copolymers contained 2–15 mol% ester units. MDP was also copolymerized with styrene (S) at 120°C with di-t-butyl peroxide as the initiator to prepare the copolymer, poly(MDP-co-S). The number-average molecular weights of both types of copolymers were in the range of 6000 to 11,000, and the weight-average molecular weights were in the range of 9000 to 17,000. The melting temperatures of poly(MDP-co-E) decreased with increasing ester unit content in the copolymer. For the MDP-S copolymers, the glass transition temperatures decreased with increasing ester unit content. Both poly(MDP-co-E) and poly(MDP-co-S) were degraded by methanolysis, and their molecular weights decreased by the expected amounts based on the ester unit content.     

Case study: Voluntary agreements in environmental management at formosa plastics

Three agreements addressing environmental and safety performance, zero discharge of wastewater and sustainable development have been signed between Formosa Plastics Corporation, Texas (Formosa Plastics), and its former adversaries. The key element of the agreements is the improvement of the affected community. These agreements go beyond public information and beyond procedures for public participation. They have led to meaningful public participation and partnership and are unique in this respect. The following article explores the setup and results of each agreement. The initial agreement, the Blackburn-Formosa Agreement, signed in 1992, set the stage for subsequent partnerships. The Wilson-Formosa Zero Discharge Agreement followed in 1994. Finally, the Sustainable Development Agreement was signed by Jim Blackburn, Diane Wilson, and Formosa Plastics in late 1997. These agreements have proven very successful in avoiding disputes and helping improve company performance in environmental and safety issues. In many respects, these agreements offer a model for others in working with an affected community.     

甘肃省环境天然放射性水平研究

近年来,国内外在环境天然放射性水平研究方面做了一些工作.在国内,由于研究目的各有侧重,因而在布点原则等方面有所不同.在全国环境保护系统的天然放射性水平研究中,象甘肃省这种跨度大(东经92°13′—108°46′,北纬32°31′—42°57′)、地形地貌极其复杂(有沙漠、戈壁、山区、高原、草原、河谷盆地等)、海拔高度差别悬殊(有600m河     

自动固相微萃取-毛细管气相色谱法检测环境水中苯系物的研究

对自动固相微萃取(SPME)-毛细管气相色谱法测定环境水中苯系物的方法进行了研究。通过对环境水中苯系物在不同SPME条件的优化、筛选实验，建立了苯系物的自动固相微萃取-气相色谱的检测方法，该方法简便、灵敏、快捷、可靠，分离度高，准确性好。在0．001mg／L～1．00mg／L范围内有良好的线性关系，最低检测浓度为0．1lμg／L～0．41μg／L。样品测定的相对标准偏差为1．8％～3．5％，回收率为88％～108％，精密度和准确度均较好。     

Partition coefficients of organochlorine pesticides on soil and on the dissolved organic matter in water

The partition coefficients of organochlorine pesticides (OCPs) between the organic matter of Taichung soil and water (K_oc) were evaluated with batch-type experiments. The partition coefficients of OCPs between Aldrich humic acid and water (K_doc) were estimated with solubility enhancement method as well. In this study, the K_ocs of aldrin, heptachlor, and p,p′-DDT are greater than their K_docs, and the relationship of dieldrin and heptachlor epoxide are opposite. The variations of partition coefficients are discussed. For predicting K_doc, a log-log regression relationship of K_doc and K_ow is determined.