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331.
Incentivizing biodiversity conservation in artisanal fishing communities through territorial user rights and business model innovation 下载免费PDF全文
C. Josh Donlan 《Conservation biology》2015,29(4):1076-1085
Territorial user rights for fisheries are being promoted to enhance the sustainability of small‐scale fisheries. Using Chile as a case study, we designed a market‐based program aimed at improving fishers’ livelihoods while incentivizing the establishment and enforcement of no‐take areas within areas managed with territorial user right regimes. Building on explicit enabling conditions (i.e., high levels of governance, participation, and empowerment), we used a place‐based, human‐centered approach to design a program that will have the necessary support and buy‐in from local fishers to result in landscape‐scale biodiversity benefits. Transactional infrastructure must be complex enough to capture the biodiversity benefits being created, but simple enough so that the program can be scaled up and is attractive to potential financiers. Biodiversity benefits created must be commoditized, and desired behavioral changes must be verified within a transactional context. Demand must be generated for fisher‐created biodiversity benefits in order to attract financing and to scale the market model. Important design decisions around these 3 components—supply, transactional infrastructure, and demand—must be made based on local social‐ecological conditions. Our market model, which is being piloted in Chile, is a flexible foundation on which to base scalable opportunities to operationalize a scheme that incentivizes local, verifiable biodiversity benefits via conservation behaviors by fishers that could likely result in significant marine conservation gains and novel cross‐sector alliances. Incentivar la Conservación de la Biodiversidad con Comunidades de Pesca Artesanal por medio de Derechos de Uso Territorial y la Innovación de Modelos de Negocio 相似文献
332.
在STIRPAT模型的基础上,通过加入能源消费需求、工业化水平和产业集聚度变量,建立了拓展的STIRPAT模型,并使用动态面板GMM方法,分析了我国30个省会城市和直辖市2003-2012年间的面板数据,指出不同的城市规模与集聚程度会对空气质量有不同的影响。首先。从总体上来说,城市人口规模、富裕程度和技术水平是影响城市空气质量的主要因素,其中人口规模和技术水平对空气质量的影响均为正效应,而富裕程度对空气质量的影响呈现出倒N型EKC曲线形状;较高的能源消费需求和工业化水平会恶化空气质量,而较高的技术水平和产业集聚度会改善空气质量,这表明相关部门可以从不断提高科技水平和产业集聚度入手,通过各种方法减少能源消费需求、降低工业化水平。来达到改善空气质量的目的。其次,在总体回归的基础上,本文重点按照人口规模、经济规模和经济集聚度、人口集中度分析了城市规模与集聚对空气质量的影响情况。结果表明:欠发达城市和大中城市的回归结果与总体回归结果一致,而经济发达城市和特大城市的回归结果与总体回归结果有一定差异,本文认为导致这些差异的主要原因是科学事业费支出方向、社会消费品结构以及工业清洁能源利用及其利用效率等因素;低产业集聚度和低人口集中度城市的情形与总体较为相近,而高产业集聚度和高人口集中度城市的EKC曲线形状与工业化水平系数与总体结果相反,这两种差异分别与城市的发展阶段和城市的人口素质有关。因此,城市的相关部门在追求规模经济的同时应该注重科技投入结构的改善,注重提高能源使用效率和清洁能源的使用率,并且在不断提高产业集聚度与人口集中度的同时追求绿色GDP的实现,注重人口的文化教育以提高人口素质,从而提升公众的环保意识,以抵消随人口集中度提高带来的环境压力。 相似文献
333.
334.
亢万忠 《石油化工环境保护》1998,(4):33-36
在分析了大型化肥装置酸气处理的现状和发展趋势后,总结了大型化肥装置酸气的特点,并对两种可供选择的酸气处理方法进行了比较。 相似文献
335.
Pesticide pollution of surface waters represents a considerable hazard for the aquatic environment. However, the mean amount of pesticides reaching the water resources varies considerably between regions and depends highly upon application rates, chemical characteristics of pesticides and natural conditions during application. In this study a model was developed which estimates loss of 42 active ingredients applied to 11 field crops, vineyards and orchards along each non-point source path of entry (subsurface drains, runoff and spray drift). A spatially and temporally differentiated data set of application rates and periods was compiled for each active ingredient and target culture to enable the modeling of pesticide transport. The model results are provided in digital raster format (100 m×100 m) within a geographic information system (GIS). The calculated pesticide loads in surface waters were compared with measured loads from different catchments in Germany. Both data sets agreed as to the order of magnitude, nevertheless due to the scale of the study the estimated loads cannot be interpreted as absolute values and only differences between active ingredients, regions and application periods should be assessed. 相似文献
336.
本文报道了含氮有机膦及其叔胺氧化物在冷却水系统中的缓蚀与阻垢性能,结果表明,叔胺氧化物与Na_2MoO_4复配时呈现出良好的协同效应. 相似文献
337.
汾河流域景观破碎化时空演变特征 总被引:3,自引:0,他引:3
以1990年、2000年、2015年遥感影像解译数据为基础,利用Fragstats 4.2软件分别采取标准法和移动窗口法获取最佳分析尺度;在此基础上探索各景观指数空间分异特征,揭示流域景观破碎化时空演变过程;采用空间自回归模型分析景观破碎化的影响因子。结果表明:随着粒度和幅度的改变,部分景观指数呈现一定规律性,90 m栅格大小、900 m方形窗口尺寸为研究区最佳分析尺度;斑块密度、蔓延度、有效网格大小、香农多样性指数在三个时期均存在空间集聚效应,且空间集聚类型分布形态具有较强的相似性;1990-2015年汾河流域景观破碎化空间分布格局发生明显变化,破碎化集聚区域呈现碎斑化;坡度、高程、距建设用地距离是影响三个时期流域景观破碎化的主要影响因素。 相似文献
338.
对钢铁厂铁鳞、铁红的基本物化性能和还原性能进行了研究。结果表明:粒度较粗、全铁较高铁鳞的还原性较好,适于作为优质海绵铁的原料。粒度极细、全铁高且杂质含量很低的铁红还原性也较好,适于作还原铁粉生产的原料。 相似文献
339.
Feng Yingsheng 《环境科学学报(英文版)》1991,3(2):1-10
The late start of environmental protection in Hong Kong was discussed in the light of problems encountered during the development of environmental protection legislation in Hong Kong for the past 20 years. The collaboration in monitoring and assessment of environmental pollutants between the University of Hong Kong and various governments were descrbed in parallel with the progress in environmental protection in Hong Kong. The developments of new analytical techniques for environmental monitoring and analysis is given and their application in environmental control described. The joint projects in assessment and control of environmental pollutants carried out in collaboration with local industries and other organizations within and without the university are given and discussed. The problems and possible solution facing Hong Kong in development control equipment for small scale industries are discussed and areas of development identified. The development and experience in the monitoring assessment and co 相似文献
340.
Turbulent flow over a two-dimensional steep hill was analyzed by large-eddy simulations (LES). Here, six LES computations were carried out using four different sub-grid scale (SGS) models and two different ground surface conditions. The accuracy of these computations was assessed by comparing the results with those from an experiment by Ishihara et al. (An experimental study of turbulent boundary layer over a steep hill, Proceedings of the 15th National Symposium on Wind Engineering, 1998, pp. 61–66; J. Wind Eng. 89 (2001) 573). The results of the dynamic SGS models were in very poor agreement with those of the experiment. The poor prediction accuracy was mainly caused by the inaccurate estimation of the model coefficient near the ground surface. In order to improve the prediction accuracy of the dynamic SGS models, a hybrid SGS model, i.e., a combination of the standard Smagorinsky model and the dynamic Smagorinsky model, was introduced. The hybrid model provided very accurate predictions and produced the best results of the four SGS models compared here. 相似文献