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排序方式: 共有71条查询结果,搜索用时 15 毫秒
1.
基于水质协议的跨界流域生态补偿标准研究   总被引:6,自引:3,他引:3  
在完全信息的情况下,分析了如何设计跨界流域生态补偿标准,并讨论了跨界流域生态补偿政策可能存在的时间一致性问题.基于斯坦伯格博弈框架下的分析结果表明,若考虑跨界流域生态补偿标准与环境损害函数是线性的,则跨界流域生态补偿政策是具有时间一致性的环境经济政策,这是由于该政策在设计时,其补偿标准要么仅与环境损害成本有关,或直接与流域内各区域的污染物削减费用有关.在这两种情况下,流域内各区域在执行该政策的时候,没有相应的战略去刺激流域内各区域刻意改变其自身的污染物削减费用函数,从而影响到未来的跨界流域生态补偿政策的实施.随后,利用该方法针对COD指标,模拟了2008年河南省贾鲁河流域跨界流域生态补偿政策,结果发现,当生态补偿标准设置在2714.13元.t-1时,能够实现跨界流域生态补偿政策的目标.在这种情况下,该流域COD排放总量达到了流域COD年允许排放总量的要求;且相比跨界流域生态补偿政策实施前,强制要求流域内各区域单独削减COD达到断面年允许排放量的情况,各区域的COD削减费用均有所下降.  相似文献   
2.
目的通过失效物理手段得到温度加速寿命试验的失效机理突变点,节省试验样本,并为加速寿命试验的有效性提供保障。方法利用电子产品典型失效物理模型,在求解MOSFET器件激活能的基础上确定失效机理突变点,并开展失效物理分析,从微观分析的角度验证失效机理一致性判定方法的理论正确性和工程适用性。结果 MOSFET器件在温度低于240℃时,失效机理没有发生改变;温度高于240℃时,失效机理发生了改变,与前述失效机理不一致。结论基于失效物理的方法可以确定器件机理发生变化的温度应力点,所需样本量小。  相似文献   
3.
Accurate discharge simulation is one of the most common objectives of hydrological modeling studies. However, a good simulation of discharge is not necessarily the result of a realistic simulation of hydrological processes within the catchment. We propose an evaluation framework that considers both discharge and water balance components as evaluation criteria for calibration of the Soil and Water Assessment Tool (SWAT). In this study, we integrated average annual values of surface runoff, groundwater flow, and evapotranspiration in the model evaluation procedure to constrain the selection of good model runs for the Little River Experimental Watershed in Georgia, United States. For evaluating water balance and discharge dynamics, the Nash‐Sutcliffe efficiency (NSE) and percent bias (PBIAS) were used. In addition, the ratio of root mean square error and standard deviation of measured data (RSR) was calculated for individual segments of the flow duration curve to identify the best model runs in terms of discharge magnitude. Our results indicate that good statistics for discharge do not guarantee realistic simulations of individual water balance components. Therefore, we recommend constraining the ranges of water balance components to achieve a more realistic simulation of the entire hydrological system, even if tradeoffs between good statistics for discharge simulations and reasonable amounts of the water balance components are unavoidable. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.  相似文献   
4.
Abstract: Indigenous people inhabit approximately 85% of areas designated for biodiversity conservation worldwide. They also continue to struggle for recognition and preservation of cultural identities, lifestyles, and livelihoods—a struggle contingent on control and protection of traditional lands and associated natural resources (hereafter, self‐determination). Indigenous lands and the biodiversity they support are increasingly threatened because of human population growth and per capita consumption. Application of the Endangered Species Act (ESA) to tribal lands in the United States provides a rich example of the articulation between biodiversity conservation and indigenous peoples' struggle for self‐determination. We found a paradoxical relationship whereby tribal governments are simultaneously and contradictorily sovereign nations; yet their communities depend on the U.S. government for protection through the federal‐trust doctrine. The unique legal status of tribal lands, their importance for conserving federally protected species, and federal environmental regulations' failure to define applicability to tribal lands creates conflict between tribal sovereignty, self‐determination, and constitutional authority. We reviewed Secretarial Order 3206, the U.S. policy on “American Indian tribal rights, federal–tribal trust responsibilities, and the ESA,” and evaluated how it influences ESA implementation on tribal lands. We found improved biodiversity conservation and tribal self‐determination requires revision of the fiduciary relationship between the federal government and the tribes to establish clear, legal definitions regarding land rights, applicability of environmental laws, and financial responsibilities. Such actions will allow provision of adequate funding and training to tribal leaders and resource managers, government agency personnel responsible for biodiversity conservation and land management, and environmental policy makers. Increased capacity, cooperation, and knowledge transfer among tribes and conservationists will improve biodiversity conservation and indigenous self‐determination.  相似文献   
5.
This communication summarizes the main findings of INASUD, an European-wide research project on integrated assessment of climate policies. The project aimed at improving the framing of climate policy analysis through the parallel use of various existing integrated assessment models. It provides a comprehensive examination of the link between uncertainty regarding damages and inertia in economic systems. Results show that the Kyoto targets and timing are consistent with the precautionary principle but offers little insurance for longer-term climate protection. Flexibility mechanisms offer potentials for cooperation with developing countries, and are necessary to tap the environmental and economic benefits of joint carbon and sulfur emissions abatement.  相似文献   
6.
淮河干流及主要支流夏季浮游植物群落生物多样性评价   总被引:6,自引:0,他引:6  
浮游植物是水生态系统的重要组成部分,其群落变化与水体环境条件密切相关,是反映河流健康的主要生物指标.为揭示淮河流域浮游植物群落特征及其与水质的相互关系,于2015年夏季对淮河流域典型水体—淮河干流、沙颍河、涡河和淠河进行系统的水质及浮游植物调查,探明浮游植物群落及其空间分布特征,并结合水体理化指标和生物指数进行水质评价.结果表明,淮河干流及主要支流27个点位中共获得浮游植物8门71属153种,主要隶属于绿藻门(Chlorophyta)、硅藻门(Bacillariophyta)、蓝藻门(Cyanophyta).浮游植物密度为0.019×10~5~131.824×10~5ind·L~(-1),不同河段浮游植物分布表现出较为显著的空间差异性,平均密度大小呈现沙颖河淮河干流涡河淠河的特点.非参数多维尺度分析(Non-metric Multidimensional Scaling,NMDS)表明,淮河干流、淠河和涡河的浮游植物群落组成和结构的相似性较高,而与沙颍河的浮游植物群落存在一定的差异.Shannon多样性指数H'介于0.78~3.21之间,Margalef丰富度指数D介于1.03~4.79之间,Pielou均匀度指数J介于0.12~0.73之间.水质生物评价结果显示,淮河流域大部分水体处于中等污染状况,部分点位处于重污染状况,其结果与水质综合污染指数评价结果具有较好的一致性.研究结果可为淮河水污染防治和水生态修复提供基础依据.  相似文献   
7.
ABSTRACT: The techniques of conflict analysis derived from game theory were applied to the Shoal Lake water supply conflict in southeastern Manitoba, Canada. The issue of conflict is the desire of an Indian Band in the area to build cottage lots near the intake for water supply for the City of Winnipeg. The City of Winnipeg contends that such a development would seriously affect the quality of water supplied to the City, thereby increasing its treatment costs significantly. The four major players defined for the conflict are the City of Winnipeg, Indian Band No. 40, the Province of Manitoba, and the Federal Department of Indian and Northern Affairs. The results of the conflict analysis suggest that the introduction of the provincial and federal government into the conifict will not assist significantly in its resolution and that further progress on the resolution is unlikely until the results of Federal Environment Assessment Review office hearing become available.  相似文献   
8.
吴丽  廖利 《环境科学与技术》2005,28(6):66-67,98
提出了基于预测有效度一致的城市生活垃圾产生量最优组合预测模型,该模型在组合预测之前利用Kendall一致性检验法对参加组合的单项预测模型值的拟合精度进行一致性检验,在通过检验之后再利用方差倒数法求解最优组合权重,建立组合预测模型。通过实例分析,表明其预测精度高于参加组合的各单项模型预测值,在城市生活垃圾产生量的预测工作中有一定的应用价值。  相似文献   
9.
锅炉烟气脱硫技术发展综述   总被引:4,自引:0,他引:4  
在调查研究的基础上,论述国内外烟道气脱硫技术的发展与前景,提出开发生产适合我国国情的烟气脱硫技术势在必行。还简要介绍了最为普遍的石灰/石灰石法脱硫基本原理。  相似文献   
10.
层次分析法已在环境科学研究中得到广泛应用。为了科学地应用群组AHP进行环境科学研究。本文提出一种几何距离最小二乘方法用于解决群组AHP排序问题。鉴于不同专家所给判断矩阵质量上的差异,GLSM排序方法对群组AHP进行不同程序的加权处理,并进行群组一致性检验。  相似文献   
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