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991.
昆明“3·29”森林火灾对防控林区火灾的启示   总被引:2,自引:1,他引:1  
介绍昆明的“3·29”森林火灾基本情况。在对该火烧迹地进行3年跟踪调研的基础上,总结了该火灾对防控西南林区森林火灾的6点启示:(1)紫茎泽兰入侵区应慎修生土隔火带;(2)通过发挥山沟的阻火作用、营林防火、森林可燃物制炭等技术措施构建阻火林分;(3)重视森林火灾次生灾害;(4)开发新型森林灭火剂及施用技术;(5)适时运用以火灭火战术;(6)探索与集体林权制度改革相适应的森林消防对策。  相似文献   
992.
Only with a properly designed water quality monitoring network can data be collected that can lead to accurate information extraction. One of the main components of water quality monitoring network design is the allocation of sampling locations. For this purpose, a design methodology, called critical sampling points (CSP), has been developed for the determination of the critical sampling locations in small, rural watersheds with regard to total phosphorus (TP) load pollution. It considers hydrologic, topographic, soil, vegetative, and land use factors. The objective of the monitoring network design in this methodology is to identify the stream locations which receive the greatest TP loads from the upstream portions of a watershed. The CSP methodology has been translated into a model, called water quality monitoring station analysis (WQMSA), which integrates a geographic information system (GIS) for the handling of the spatial aspect of the data, a hydrologic/water quality simulation model for TP load estimation, and fuzzy logic for improved input data representation. In addition, the methodology was purposely designed to be useful in diverse rural watersheds, independent of geographic location. Three watershed case studies in Pennsylvania, Amazonian Ecuador, and central Chile were examined. Each case study offered a different degree of data availability. It was demonstrated that the developed methodology could be successfully used in all three case studies. The case studies suggest that the CSP methodology, in form of the WQMSA model, has potential in applications world-wide.  相似文献   
993.
通过对昌吉州农村水环境、空气质量及土壤调查现状的监测分析,获取农村环境现状情况,依据取得的数据综合评价农村环境的动态变化趋势。并在此基础上,进一步探讨农村环境存在的问题及提出可行的对策及建议。  相似文献   
994.
Specialised literature on the uptake of agri-environmental schemes (AES) has paid little attention to how this can be influenced by the different types of agricultural systems. This paper analyses the heterogeneity of farmers' preferences towards these schemes, distinguishing between different subsystems within the same agricultural system. We use the choice experiment method to analyse the case study of three olive grove subsystems in southern Spain, with the subsystems ranging from extensive to intensive. The results reveal inter- and intra-subsystem heterogeneity of farmers' preferences towards AES, both in general and specifically related to scheme attributes. A variety of factors appear to lie behind inter-subsystem heterogeneity, especially those associated with subsystem specificities (principally, the type of joint production). Likewise, numerous factors play a role in intra-subsystem heterogeneity, most of them related to farm/farmer socio-economic and physical characteristics. These findings will help in the design of more efficient AES.  相似文献   
995.
Abstract: Bioretention as sustainable urban stormwater management has gathered much recent attention, and implementation is expanding in mesic locations that receive more than 1,000 mm of annual precipitation. The arid southwestern United States is the fastest growing and most urbanized region in the country. Consequently, there is a need to establish design recommendations for bioretention to control stormwater from expanding urban development in this ecologically sensitive region. Therefore, we review the ecological limits and opportunities for designing bioretention in arid and semiarid regions. We incorporated USEPA Stormwater Management Model (SWMM) simulations to synthesize ecologically based design recommendations for bioretention in arid climates. From our review, an ideal bioretention garden area should be 6 to 8% of the contributing impervious drainage area (depending on region) with two layers of media, a 0.5‐m low‐nutrient topsoil layer above a 0.6‐m porous media layer that acts as temporary storage during a storm event. When planted with the suggested vegetation, this design maximizes stormwater treatment by promoting ecological treatment in the topsoil while promoting infiltration and evapotranspiration of stormwater by deep‐rooted shrubs that require no irrigation after establishment. This synthesis improves water resources management in arid and semiarid regions by introducing a sustainable bioretention design that protects local surface waters while reducing regional water demands for irrigation.  相似文献   
996.
Spence, Porchè L., Deanna L. Osmond, Wesley Childres, Joshua L. Heitman, and Wayne P. Robarge, 2012. Effects of Lawn Maintenance on Nutrient Losses Via Overland Flow During Natural Rainfall Events. Journal of the American Water Resources Association (JAWRA) 48(5): 909‐924. DOI: 10.1111/j.1752‐1688.2012.00658.x Abstract: A sampling system was used to evaluate the effect of residential lawn management on nutrient losses via overland flow generated during natural rainfall events from three residential landscapes: a high maintenance fescue lawn (HMFL), a low maintenance fescue lawn (LMFL), and a mixed forested residential landscape (FRL). A sampling system was located in designated areas within each landscape such that 100% of the runoff follows natural flow paths to the outlet ports and collects in sterile Nalgene® B3 media bags (Thermo Fisher Scientific, Rochester, NY). A rainfall event was defined as producing ≥2.54 mm of water. A total of 87 rainfall events occurred during a 20‐month monitoring period. The total runoff volume collected from the LMFL was higher than from the HMFL and FRL, but on average <1% of the total rainfall was collected from the three landscapes. Mean nitrate concentrations from each lawn did not exceed 0.6 mg N/l. Nutrient unit area losses from the HMFL, LMFL, and FRL were 1,000 times less than fertilizer and throughfall inputs, which were due to the presence of well‐structured soils (low bulk densities) with high infiltration rates. This study demonstrated that the frequency of runoff, total runoff volumes, and nutrient losses during natural rainfall events are lower from highly maintained (i.e., irrigation, fertilizer application, and reseeding) densely uniform manicured lawns than low maintenance lawns and forested residential landscapes.  相似文献   
997.
The International Union for the Conservation of Nature World Parks Congress in 2014 reported that the quality of management of protected areas is crucial in halting the loss of the world’s biodiversity and meeting global environmental challenges. However, increasingly high-impact activities, including motorized recreation are occurring in protected areas such as national parks, creating an ongoing clash of values and further compromising protected area management. This paper discusses the values of protected areas in the context of increasingly high-impact motorized usage, the impact of divergent values placed on green spaces such as national parks, and perceptions about these spaces. Given the changing global context of this millennium, and increasing populations requiring space for high-impact activities including motorized recreation, rethinking recreation in protected areas is needed. A protected area classification to accommodate high-impact activities away from vulnerable natural areas may assist in maintaining protected area quality.  相似文献   
998.
随着农村土地制度的变化,安置区土地补偿问题对于协调水库移民安置中各相关主体之间的利益平衡具有重要的意义。本文基于实地调查,首先分析了水库移民安置区土地补偿的现状和存在的问题;其次,运用土地产权理论和福利经济理论,从安置区土地补偿的原因、范围和补偿原则等方面阐明了安置区土地补偿的基本原理;最后,在此基础上提出了完善相关法律法规、协调水利水电工程建设中利益相关者的关系和利益平衡、体现农地价值等政策建议。结果表明:其一,安置区的土地补偿,无论从现行法律、还是从实际获得的补偿来看,均未体现对安置区土地权益的保护;其二,安置区集体和居民理应获得相应的权益补偿,其补偿范围既包括转出土地使用权的补偿,也包括对共同拥有土地所有权带来的权益分配变化的补偿;其三,土地制度的建设和改进上,应依据安置区土地资源状况和调出土地的状况确定补偿标准,淹没区集体、移民和安置区集体、居民应获得同等补偿,并力求体现农地价值。  相似文献   
999.
ABSTRACT

This paper investigates the spatial effect of environmental regulation measures on the upgrading of industrial structure in the integrated development strategy of Beijing-Tianjin-Hebei region and its surrounding areas. In order to reflect the effect of the environmental regulation and different regulation measures more truly, this paper constructs indices of the environmental regulation measures through the results of policy texts quantification. On the basis of the previous research, this paper divides environmental regulation into the following types: personnel and administrative measures of command and control; market-oriented fiscal, taxation, financial and other economic measures; guidance measures. Spatial panel regression results show that administrative measures of command control and market-oriented fiscal measures have a significant role in promoting regional industrial structure upgrading, but not conducive to the advancement of the industrial structure of adjacent areas. Their roles in promoting and inhibition are counteracted, which causes the total effect of industrial structure upgrading of Beijing-Tianjin-Hebei and the surrounding areas are not significant. Personnel measures, financial measures, other economic measures and guidance measures do not have the short-term effect and spatial effect on the upgrading of industrial structure.  相似文献   
1000.
贫困地区农民真的从“新农合”中受益了吗   总被引:1,自引:0,他引:1  
基本公共服务受益均等化要求新型农村合作医疗服务应有效地保障贫困地区的农民大致均等地享受该服务。本文运用边际受益归宿分析技术,实证测度了2007-2011年中国244个地级市(州)的新农合边际受益率,来探究贫困地区的农民是否真的从新农合中受益。研究发现:第一,与富裕地区相比,贫困地区的新农合边际受益率更高。2007-2011年,最贫困地区的新农合边际受益率分别为1.287 8、1.179 3、1.065 9、0.985 7和1.202 7,最富裕地区的新农合边际受益率分别为0.751 8、0.671 6、0.597 6、0.888 8和0.922 9。第二,从动态角度观察,贫困地区与富裕地区新农合边际受益率的差值在逐渐缩小。2007年,最贫困地区和最富裕地区的新农合边际受益率相差0.536 0,2011年,这一差值缩小为0.279 8。第三,传统的平均受益分析低估了贫困地区的新农合受益水平。以2007年为例,通过平均受益分析得到的最贫困地区的受益份额为24.20%,而边际受益归宿分析结果显示,最贫困地区从整体新农合受益提高中增加的受益份额达到了32.20%,较平均受益份额高出8个百分点,亦即,贫困地区的农民从新农合服务的扩张中可以获得更大的受益,在新农合服务的缩减中可能遭受更大的损失。本文的结论表明,国家在新农合中"亲贫"的政策倾向更多地惠及了贫困地区,新农合的受益均等化程度越来越高。为保证贫困地区的农民在更大程度上受益,政府应实施"精准医保扶贫",加大新农合投入;多元化新农合服务供给渠道,加强地区间协调配合;优化新农合资源配置,完善对地方政府和相关官员的激励约束机制,提高贫困地区新农合的生产效率。  相似文献   
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