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101.
退耕还林工程费用有效性的影响因素分析   总被引:3,自引:0,他引:3  
费用有效性评价是工程评价的重要方面。从政策制定和执行角度对退耕还林的费用有效性及其影响因素进行分析。具有重要的意义。利用实地调研数据和相关统计数据.从退耕地选择和造林入手对退耕还林工程实施的费用有效性殛其影响因素进行考察.并尝试对这些因素的作用机制进行了分析。研究指出由于缺乏长期的和有效的退耕还林规划以及相关政策措施的缺失.使得退耕还林费用有效性的损失在微观层面和宏观层面广泛存在。而各利益主体的利益不相害性是影响工程有效实施的基本矛盾。有必要在遇耕还林中确立明确的规划、清晰的退耕地选择标准。建立和完善管理信息系统和及时有效的反馈和控制机制。构建协调多方利益的长期稳定的生态补偿机制。从而改进退耕还林工程的费用有效性。  相似文献   
102.
An effective environmental public health tracking system integrates data and intelligence on environmental hazards, exposures, and health outcomes to focus interventions on reducing the impact of environmental contamination on public health. Most work in this area in the UK has focused on assessing data on hazards that are relatively easy to obtain. However, most hazards will present no actual risk and information on exposure is required to make an effective risk assessment. Obtaining exposure data is technically challenging, expensive, and potentially raises ethical concerns. Consequently, the Health Protection Agency is exploring methods for targeting geographical zones for efficient detailed environmental assessment (including exposure assessment). This paper describes and assesses three methods (indirect standardization, statistical process control (SPC) and kernel density contouring) for the surveillance of potentially environmentally related diseases for this purpose. While the evaluation demonstrates the utility of the three methods, particularly SPC, the comparison was limited due to ethical approval issues.  相似文献   
103.
104.
Residential mobility and personal well-being   总被引:1,自引:0,他引:1  
This research examines the relationship between personal mobility rate (number of lifetime moves/respondent's age) and health status. A contextual analysis is proposed in which the health consequences of relocation depend not only on the immediate circumstances surrounding a move, but also on the broader context of the individual's residential history, current life situation, and aspirations for the future. Two hundred and forty-two adult employees completed an initial survey of lifetime residential history, current residential desirability, employment experience, and perceived housing options for the future. Three months later, a panel group of 121 respondents completed a follow-up survey of emotional and physical well-being. Frequent relocation was directly associated with a greater number of illness-related symptoms, but the impact of mobility rate was largely mediated by psychological factors. Health problems were more prevalent among high-mobility individuals characterized by low rather than high levels of environmental exploratory tendency; among low-mobility persons reporting low versus high levels of residential choice and congruence; and among low residential-quality individuals who perceived future residential options to be unavailable rather than available.  相似文献   
105.
ABSTRACT: This study examines the extent to which knowledge deficits pose a significant barrier to public support for nonpoint pollution management strategies. Such barriers would obtain if all of the following conditions are present: (1) many in the public lack knowledge relevant to those strategies; (2) variations in knowledge are linked only to relatively unchanging personal attributes; and (3) individuals with more knowledge are more likely to support the implementation of management strategies. Each of these conditions is subjected to empirical analysis in this study. The findings reported here derive from a survey of citizens in Spokane, Washington, the site of a major 208 Water Quality Management Program study. The results of the survey indicate that: portions of the public have enough knowledge to evaluate technically based management strategies; sources of public knowledge are sufficiently elastic that both policy area concern and policy relevant knowledge can be elevated in the short run; and both knowledge levels and general attitudes are related to the public's specific water policy preferences. The study concludes that the apparent lack of knowledge among the public is not necessarily a significant barrier to policy implementation, and that support for implementation may be generated through both knowledge enhancement and the tapping of existing political orientations through the placement of emphasis upon the seriousness of water resource problems.  相似文献   
106.
ABSTRACT: This paper is a computer simulation analysis of an agricultural nonpoint pollution problem. Computer modeling is a universally applicable tool that can be used for establishing the linkages between and the quality of agricultural runoff in both surface and subsurface flow. The tradeoffs between the costs of soil conservation practices and water quality are reported, and the economic implications of such tradeoffs are discussed. Soil and nutrient losses resulting from crop production practices are analyzed using a field-scale computer simulation model (CREAMS). No-till planting, reduced tillage, and sod waterway systems are more cost effective than other practices for controlling soil and nutrient runoff losses. Nitrate leaching losses are increased slightly by most soil conservation practices. Terrace systems and permanent vegetative cover impose the greatest societal cost for water quality protection. Public cost sharing and tax incentives encourage farmers to adopt expensive structural practices, and policies are needed to get cost-effective practices implemented on critical acreage. Extensive treatment of land is necessary for agricultural best management practices (BMPs) to significantly improve water quality in areas that are intensively farmed.  相似文献   
107.
The Agricultural Conservation Program (ACP), is undergoing a new, rigorous evaluation to determine its effectiveness in conserving the Nation's agricultural soils and waters. ACP deals with many types of conservation practices, but the focus here is on the evaluation of soil and water related practices. ACP has depended heavily on the State and private forestry services, Soil Conservation Service, and the Cooperative Extension Services, for technical expertise. Thus, the process is an evaluation of the effectiveness of a “team of agencies,” as well as of the program itself. Results of the evaluation have helped to develop new thrusts which have moved ACP further into the position of treating the total conservation problem. Phase I has its limitations. It did not address the impact of wind erosion, water quality, change in productive capacity, soil quality, wildlife habitat, off site and farm income impacts. It does show that ACP has and is doing a very good job in meeting its stated purposes. It is clear that ACP's effectiveness can be improved with more and better advanced planning and more intensive use of soil maps, the USLE, and other scientific tools. ACP is headed in this direction.  相似文献   
108.
The Toxics Use Reduction Act (TURA) model is widely cited as an effective blend of mandatory and voluntary components, and is considered a model nation-wide and internationally. There is ample documentation of the reductions in toxic chemical use achieved by Massachusetts facilities under TURA. The present study was designed to gather other information about the experience of these facilities. Through an online survey and telephone interviews, the study investigated how these facilities are achieving toxics use reduction, how TURA affects internal company dynamics, what benefits and difficulties facilities experience, and how their experiences in the program have changed over time. Survey results indicate that the benefits experienced most frequently by facilities subject to TURA requirements are increased management attention to environmental practices; improved worker health and safety; and financial savings. Most frequently cited obstacles to TUR implementation are technical feasibility problems; financial costs; concerns about product quality; and customer requirements. Survey results also indicate that the TUR planning process is most useful in the first and second planning cycles, although most respondents indicated that they sometimes identify useful TUR options in subsequent planning cycles as well. Over all, the results indicate that facilities are continuing to experience significant benefits from the TURA program, while they also continue to face some challenges. These results provide a snapshot of the experience of Massachusetts facilities 20 years since the inception of the TURA program. They also provide baseline information that will be useful for later evaluations of the effects of statutory changes to TURA adopted in 2006 and implemented in subsequent years. The study also included a preliminary assessment of the experience of Massachusetts municipal agencies, community organizations, small business associations and others that receive assistance from the TURA program.  相似文献   
109.
Assessing the scope and severity of threats is necessary for evaluating impacts on populations to inform conservation planning. Quantitative threat assessment often requires monitoring programs that provide reliable data over relevant spatial and temporal scales, yet such programs can be difficult to justify until there is an apparent stressor. Leveraging efforts of wildlife management agencies to record winter counts of hibernating bats, we collated data for 5 species from over 200 sites across 27 U.S. states and 2 Canadian provinces from 1995 to 2018 to determine the impact of white-nose syndrome (WNS), a deadly disease of hibernating bats. We estimated declines of winter counts of bat colonies at sites where the invasive fungus that causes WNS (Pseudogymnoascus destructans) had been detected to assess the threat impact of WNS. Three species undergoing species status assessment by the U.S. Fish and Wildlife Service (Myotis septentrionalis, Myotis lucifugus, and Perimyotis subflavus) declined by more than 90%, which warrants classifying the severity of the WNS threat as extreme based on criteria used by NatureServe. The scope of the WNS threat as defined by NatureServe criteria was large (36% of Myotis lucifugus range) to pervasive (79% of Myotis septentrionalis range) for these species. Declines for 2 other species (Myotis sodalis and Eptesicus fuscus) were less severe but still qualified as moderate to serious based on NatureServe criteria. Data-sharing across jurisdictions provided a comprehensive evaluation of scope and severity of the threat of WNS and indicated regional differences that can inform response efforts at international, national, and state or provincial jurisdictions. We assessed the threat impact of an emerging infectious disease by uniting monitoring efforts across jurisdictional boundaries and demonstrated the importance of coordinated monitoring programs, such as the North American Bat Monitoring Program (NABat), for data-driven conservation assessments and planning.  相似文献   
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