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191.
We conducted a natural resource assessment at two national parks, New River Gorge National River and Shenandoah National Park,
to help meet the goals of the Natural Resource Challenge—a program to help strengthen natural resource management at national
parks. We met this challenge by synthesizing and interpreting natural resource information for planning purposes and we identified
information gaps and natural significance of resources. We identified a variety of natural resources at both parks as being
globally and/or nationally significant, including large expanses of unfragmented, mixed-mesophytic forests that qualify for
wilderness protection, rare plant communities, diverse assemblages of neotropical migratory birds and salamanders, and outstanding
aquatic recreational resources. In addition, these parks function, in part, as ecological reserves for plants in and wildlife.
With these significant natural resources in mind, we also developed a suite of natural resource management recommendations
in light of increasing threats from within and outside park boundaries. We hope that our approach can provide a blueprint
for natural resource conservation at publically owned lands. 相似文献
192.
借鉴国内外 I/ M制度的经验 ,运用系统论、控制论的观点 ,创造性地提出有效治理城市汽车尾气污染应建立的六大体系 ,强调城市汽车尾气污染的控制应以尾气污染预前控制和过程控制为主 ,并以此构筑城市汽车尾气污染治理的新模式 相似文献
193.
Impact of poor solid waste management on ground water 总被引:1,自引:0,他引:1
Eight sediment cores recovered from Tamaki Estuary were analysed for Cu, Pb, Zn, and Cd using downward cored sub-samples.
The results indicate a significant upward enrichment in heavy metals with the highest concentrations found in the uppermost
0–10 cm layer. Assessment of heavy metal pollution in marine sediments requires knowledge of pre-anthropogenic metal concentrations
to act as a reference against which measured values can be compared. Pristine values for the cored sediments were determined
from flat “base-line” metal trends evident in lower core samples. Various methods for calculating metal enrichment and contamination
factors are reviewed in detail and a modified and more robust version of the procedure for calculating the degree of contamination
is proposed. The revised procedure allows the incorporation of a flexible range of pollutants, including various organic species,
and the degree of contamination is expressed as an average ratio rather than an absolute summation number. Comparative data
for normalized enrichment factors and the modified degree of contamination show that Tamaki Estuary sediments have suffered
significant systematic heavy metal contamination following catchment urbanization. Compared to baseline values the uppermost
sediment layers show four-fold enrichment averaged across eight cores and four analysed metals. 相似文献
194.
城市土地生态适宜性分区划分研究 总被引:1,自引:0,他引:1
在新型城镇化与生态文明建设背景下,城市发展迫切需要合理布局以实现城市土地的节约集约利用,降低城市化过程中因建设用地肆意蔓延所导致的土地资源浪费与生态环境破坏影响。以常州市武进区为例,采用地形地貌、生态环境、交通设施、建设密度4类因子建立景观过程阻力赋值体系,结合GIS空间分析技术,以垂直生态过程的多因素多因子综合判别得到的生态保护用地扩张和城镇用地扩张阻力基面为基础,再以描述水平生态过程的最小累积阻力模型计算两种扩张过程的最小累积阻力值,并依据二者的最小累积阻力差值表面,从空间上将武进区划分为4个等级的城市土地生态适宜性分区,分别为优先建设区118.39 km2、适宜建设区233.60 km2、生态缓冲区777.91 km2、生态控制区115.90 km2,明确指出了各分区的空间布局,提出了相应的发展建议,以期为武进区未来城市发展提供科学合理的空间布局参考。同时考虑了垂直生态过程和水平生态过程,一定程度上弥补了传统方法只从景观单元垂直过程研究的不足之处,为生态适宜性分区划分的方法研究提供了有益的尝试和补充。 相似文献
195.
Integrated landscape planning and remuneration of agri-environmental services. Results of a case study in the Fuhrberg region of Germany 总被引:1,自引:0,他引:1
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
196.
太阳能路灯技术的国内外研究动态及其在浙江新农村建设中的应用 总被引:1,自引:0,他引:1
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
197.
Jon?BarnettEmail author Jonathan?Pauling 《Environment, Development and Sustainability》2005,7(2):271-289
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
198.
Comparative Analysis of New Zealand and US Approaches for Agricultural Nonpoint Source Pollution Management 总被引:1,自引:0,他引:1
Brian S. Caruso 《Environmental management》2000,25(1):9-22
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
199.
200.
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