上保护层开采瓦斯综合治理的试验研究

借助于一般的保护层开采理论,对上保护层开采合理参数和保护范围进行了综合分析研究,结合潘东公司具体情况设计了试验方案,现场试验结果表明了该方案的合理性,同时也表明上保护层开采对下临近突出煤层的突出危险消除效果明显,上保护层开采带来的经济和社会效益十分显著。试验结果对类似开采条件的矿井防治煤与瓦斯突出及瓦斯综合治理具有一定指导意义。     

浅析分布式防火墙技术

随着计算机网络的不断发展,现有的防火墙体系已不能满足要求,发展新的网络防火墙技术已非常重要.分布式防火墙具有明显的防护优势,了解分布式防火墙技术,并在实际应Ζ用中用好它,已成为保障我们网络安全的必要.     

北京市地热资源开发的时空变化

简要介绍了北京地热资源特点,分析了北京地热资源开发的时空演变规律.在搜集资料和实地调查的基础上,绘制出了北京城区地热井分布示意图,并针对其开发利用中可能出现的问题提出了对策.     

我国水业市场化模式

本文就我国水业的特许经营模式和市场监管等问题进行了重点讨论。     

对排污权交易的现实思考

排污权交易作为一种制度,在我国尚未完全建立.在准市场机制调整之下的排污权交易市场具有比现行排污收费制度更合理之处.排污权交易制度的目的在于逐步减少污染排放,而非刺激排污.其具有的激励和资源配置功能,不仅能较好地控制排污总量,还能提供更丰富的控制污染的方法和途径.公众甚至可以直接参与对环境的管理.本文作者试图从经济学和竞争法的角度对排污权交易的现实问题作一浅显分析.     

含油污泥特点及处理方法

含油污泥主要来源于油田开采、油气集输及污水处理场,污泥中一般含油率在10%～50%,含水率在40%～90%。文章介绍了不同来源含油污泥的特点及脱水方法,并对各种含油污泥处理方法的优、缺点进行了比较。研究结果表明,各种方法都有其特点和适用范围。由于含油污泥成分复杂,没有任何一种处理方法可以处理所有类型的含油污泥。     

Improving Operational Planning and Management of National Parks in Turkey: A Case Study

The purpose this study was to improve operational planning and management of national parks in Turkey to balance conservation use and sustainable management. Souksu National Park (SNP) was chosen as the study area. The data were obtained from interviews of 182 visitor groups (in total, 819 people) and analyzed using correlation, factor, discriminant, and regression analyses. It was found that the most important factors affecting operational planning and management of SNP are (1) travel cost, (2) visitor welfare level, (3) intensity of use, (4) size of visitor group, (5) type of recreational demand. The main source of visitors to SNP is from a zone within a 0–90-km radius. This region comprised 53.85% of total visitors to the park. The capital of Turkey (Ankara) is the most important source of visitors from within this zone. The optimum activity mix in SNP is also determined. Picnicking, viewing the scenery, and nature walks or trekking comprised the main uses of the park. It is anticipated that these findings will help to improve operational planning and sustainable management of the national park and the environment.     

Quantifying and Evaluating Ecosystem Health: A Case Study from Moreton Bay, Australia

As part of the program monitoring the ecosystem health of Moreton Bay, Queensland, Australia, we developed a means for assessing ecosystem health that allows quantitative evaluation and spatial representations of the assessments. The management objectives for achieving ecosystem health were grouped into ecosystem objectives, water quality objectives, and human health objectives. For the first two groups, aspects of the ecosystem (e.g., trophic status) were identified, and an indicator was chosen for each aspect. Reference values for each indicator were derived from management objectives and compared with the mapped survey values. Subregions for which the indicator statistic was equal to or better than the assigned reference value are referred to as “compliant zones.” High-resolution surface maps were created from spatial predictions on a fine hexagonal grid for each of the indicators. Eight reporting subregions were established based on the depth and predicted residence times of the water. Within each reporting subregion, the proportion that was compliant was calculated. These results then were averaged to create an integrated ecosystem health index. The ratings by a team of ecosystem experts and the calculated ecosystem health indices had good correspondence, providing assurance that the approach was internally consistent, and that the management objectives covered the relevant biologic issues for the region. This method of calculating and mapping ecosystem health, relating it directly to management objectives, may have widespread applicability for ecosystem assessment.     

Information Network Topologies for Enhanced Local Adaptive Management

We examined the principal effects of different information network topologies for local adaptive management of natural resources. We used computerized agents with adaptive decision algorithms with the following three fundamental constraints: (1) Complete understanding of the processes maintaining the natural resource can never be achieved, (2) agents can only learn by experimentation and information sharing, and (3) memory is limited. The agents were given the task to manage a system that had two states: one that provided high utility returns (desired) and one that provided low returns (undesired). In addition, the threshold between the states was close to the optimal return of the desired state. We found that networks of low to moderate link densities significantly increased the resilience of the utility returns. Networks of high link densities contributed to highly synchronized behavior among the agents, which caused occasional large-scale ecological crises between periods of stable and high utility returns. A constructed network involving a small set of experimenting agents was capable of combining high utility returns with high resilience, conforming to theories underlying the concept of adaptive comanagement. We conclude that (1) the ability to manage for resilience (i.e., to stay clear of the threshold leading to the undesired state as well as the ability to re-enter the desired state following a collapse) resides in the network structure and (2) in a coupled social–ecological system, the systemwide state transition occurs not because the ecological system flips into the undesired state, but because managers lose their capacity to reorganize back to the desired state. An erratum to this article can be found at .