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201.
Until now, existing remuneration of environmental services has not sufficiently supported the goals of spending money more effectively on the environment and of motivating farmers. Only a small share of the budgets for agriculture in the EU, as well as in US and other countries, is available for buying environmental goods and services beyond the level of good farming practice (GFP). This combined with the insufficient targeting of compensation payments to areas where special measures are needed leads to an unsatisfactorily low impact of agri-environment measures compared to other driving forces that stimulate the intensification of farming. The goal of this paper is to propose a management concept that enhances the ecological and cost efficiency of agri-environment measures. Components of the concept are a comprehensive environmental information base with prioritised goals and targets (available in Germany from landscape planning) and new remuneration models, which complement conventional compensation payments that are based upon predetermined measures and cost. Comprehensive landscape planning locates and prioritises areas which require environmental action. It contains the information that authorities need to prioritise funding for environmental services and direct measures to sites which need environmental services beyond the level of GFP.Also appropriate remuneration models, which can enhance the cost efficiency of public spending and the motivation of the farmers, can be applied on the base of landscape planning.Testing of the planning methodology and of one of the remuneration models (success-oriented remuneration) in a case study area (“Fuhrberger Feld” north of Hanover, Germany) demonstrated the usability of the concept and led to proposals for future development of the methodology and its application in combination with other approaches.  相似文献   
202.
针对中国太阳能利用技术的现状,分析比较了太阳能路灯在国内利用的可行性,详细介绍了浙江某示范村的太阳能路灯工程情况,并对该工程进行了经济可行性的分析。  相似文献   
203.
This paper explains one way in which New Zealand’s free-market reforms have adversely affected its environment. Liberalisation of New Zealand’s economy has radically changed the determinants of agricultural export success, largely due to the elimination of subsidies to domestic producers, and of tariffs on imports. In this exposed agricultural milieu, the dairy industry has thrived; cow numbers have increased by over 50%, with commensurate increases in herd and farm sizes. With this rapid expansion has come increasing pollution of New Zealand’s waterways. New Zealand’s Resource Management Act 1991 is potentially capable of controlling these adverse effects; however, its implementation was slow and piecemeal throughout the 1990s. So, at the same time as production and pollution from dairy farming expanded, the efficacy of environmental policy was limited. The resulting implementation gap has put at risk the ‘clean and green’ image that is an important component of New Zealand’s agricultural export success.Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
204.
The role of the central government in New Zealand is generally limited to research and policy development, and regional councils are responsible for most monitoring and management of the problem. The role of the federal government in the United States includes research and monitoring, policy development, and regulation. States also have a significant management role. Both countries rely on voluntary approaches for NPS pollution management. Very few national water quality standards exist in New Zealand, whereas standards are widely used in the United States. Loading estimates and modeling are often used in the United States, but not in New Zealand. A wide range of best management practices (BMPs) are used in the United States, including buffer strips and constructed/engineered wetlands. Buffer strips and riparian management have been emphasized and used widely in New Zealand. Many approaches are common to both countries, but management of the problem has only been partly successful. The primary barriers are the inadequacy of the voluntary approach and the lack of scientific tools that are useful to decision-makers. More work needs to be performed on the evaluation of approaches developed in both countries that could be applied in the other countries. In addition, more cooperation and information/technology transfer between the two countries should be encouraged in the future.  相似文献   
205.
北京石景山地区大气中有机污染物特征与成因   总被引:13,自引:0,他引:13  
对北京石景山地区大气中有机质浓度、各族组成及其饱和烃、多环芳烃的组成和分布特征进行了分析。大气中共检测出40多种多环芳烃,其中很多属于美国国家环保局(EPA)优先控制污染物,以及具有致癌和怀疑有致癌性的多环芳烃。其主要来源于煤的不完全燃烧,也有相当部分来源于汽车尾气的排放。其中煤比石油所造成的污染更为严重。   相似文献   
206.
基于ADMS和线性规划的区域大气环境容量测算   总被引:8,自引:0,他引:8  
基于ADMS-Urban和线性规划模型,构建了浓度-排放量反推模式,从区域自然生态环境和污染气象特征出发,以区域大气环境质量保护目标为约束条件,结合虚拟点源法测算区域大气环境容量.以北京市通州区进行案例分析,根据当地自然环境与污染气象特征等信息,在环境质量目标约束条件下,应用该方法测算出通州区的SO2环境容量为41 311 t/a;但其空间分布极为不均,主要分布于建成区以外的乡镇,建成区的环境容量较小.由于通州区SO2排放主要集中在采暖期的建成区,尽管全区的SO2年排放量远小于其环境容量,但是仍然在建成区造成了严重污染.   相似文献   
207.
Previous soil lead studies in New Orleans focused on the geochemical footprint and its health impacts. This study examines the human geography of race, income, and age in pre-Katrina metropolitan New Orleans within the context of lead accumulation in soils. Sample points of soil lead data (n = 5,467) collected in 1998–2000 were mapped in a geographic information system (GIS), binned into 9 ranges, and queried by (1) 2000 Census racial demographic data, (2) 1999 median household income, and (3) 2000 age data. The absolute population generally declines as lead levels increase except at lead levels from 200–400 to 400–1,000 mg/kg when population increases; the African–American population comprises a disproportionate share of this cohort. The high-lead areas occur in the inner city, home to the largest populations of African-Americans in New Orleans. The mean household income curve indicates that lower economic groups are at risk to higher levels of lead. A total of 44,701 children under the age of 5 years, plus 123,579 children aged 5–17, lived in census block groups containing at least one sample point with over 100 mg/kg lead, and these include 23,124 and 64,064 young people, respectively, who live near at least one point over 400 mg/kg. Lead exposure affects a panoply of outcomes that influence the health and welfare of the community. Unless corrected, children are likely to return to the same or, because of lack of lead-safe practices during renovation, even higher exposure risks than before the flooding of New Orleans.  相似文献   
208.
Abstract:  Scarce resources and competing land-use goals necessitate efficient biodiversity conservation. Combining multicriteria analysis with conservation decision-support tools improves efficiency of conservation planning by maximizing outcomes for biodiversity while minimizing opportunity costs to society. An opportunity cost is the benefit that could have been received by taking an alternative course of action (i.e., costs to society of protecting an area for biodiversity rather than developing it for some other use). Although different ways of integrating multiple opportunity costs into conservation planning have been suggested, there have been no tests as to which method is most efficient. We compared the relative efficiency of 3 such procedures ( Faith & Walker [1996] , Sarkar et al. [2004] , and a procedure of our own design) in a systematic conservation-planning framework for the Milne Bay Province of Papua New Guinea. We devised 14 opportunity costs and assigned these to 3 scenarios representing different conservation planning concerns: food security, macro-economic development, and biodiversity persistence. For each scenario, we compared the efficiency of the 3 methods in terms of amount of biodiversity protected relative to total expenditure for each opportunity cost. All 3 methods captured similar amounts of biodiversity, but differed in total cost. Our method had the least overall cost and was therefore most efficient. Nevertheless, there was a high correlation and geographical concordance among all 3 methods, indicating a high degree of spatial overlap. This suggests that choosing an appropriate approach may often depend on contextual factors related to the design of the planning question, rather than efficiency alone.  相似文献   
209.
基于Delft 3D模型的大鹏湾水环境容量分析   总被引:11,自引:2,他引:9  
在污染源调查和污染负荷估算的基础上,利用Delft 3D数学模型对大鹏湾现状和未来条件下的水质进行了数值模拟,并采用模型试算法估算出大鹏湾的水环境容量.结果表明:在现状和未来条件下,大鹏湾整体水质良好,沙头角海及印洲塘的水质有下降的迹象.预测除了这2个次区外,其他次区的污染负荷到2015年仍未超出其水环境容量,建议深港双方政府采取污染物总量控制、制定社会经济发展规划等方法,以确保大鹏湾水质在现在和将来都能符合水质标准.   相似文献   
210.
沈北新区土壤中多环芳烃污染特征及源解析   总被引:10,自引:6,他引:4  
采用均匀网格布点法采集沈阳市沈北新区不同土地利用类型101个表层(0~20 cm)土壤样品,开展土壤中美国环保署优先控制的16种多环芳烃(PAHs)的含量空间分布特征、成分谱分析和污染物来源解析研究.结果表明,沈北新区土壤中16种PAHs(ΣPAHs)总含量为123.7~932.5μg·kg~(-1);PAHs组分以3~4环的中、低环组分为主,其中3环PAHs比例最高;ΣPAHs的空间分布特征明显,呈现出由南向北、自东向西逐渐递减的趋势.在研究区域所涉及的5种土地利用类型土壤中,土壤ΣPAHs含量的高值主要集中在城区绿地和人工绿化林地,其次为设施菜地,水稻田和玉米田中ΣPAHs含量相对较低且无明显空间分布差异.利用特征比值分析和因子分析/多元线性回归分析进行土壤中PAHs的污染源解析,初步确定沈北新区表土中PAHs的主要污染源为燃烧源和石油源的混合源,其中,工业燃煤和机动车尾气是PAHs的主要污染源,其贡献率达79.6%,石油泄漏和焦炉排放贡献率约为16.2%,生物质燃料的燃烧贡献率占4.2%.  相似文献   
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