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261.
262.
论我国矿业环境保护法律制度 总被引:1,自引:0,他引:1
环境保护是矿区生态协调稳定和资源可持续利用的重要保证。由于矿山环境问题十分严重,且现行的矿业环境法律体制不健全,产权不明晰,法律制度不完善,使法难以有效实施。对此,本文提出应确立良好的产权制度,严格矿业权许可,强化市场在环境保护中的作用,加强行政引导和调控机制,完善相关的法律制度。 相似文献
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264.
中国综合减灾立法体系研究--兼论立项编研国家《综合减灾法》的重要问题探讨 总被引:1,自引:2,他引:1
本文阐述了建立《综合减灾法》的背景,探讨了《综合减灾法》的作用.在国外综合减灾立法的基础上,给出了中国《综合减灾法》的编研框架. 相似文献
265.
环境影响评价中的公众参与 总被引:9,自引:0,他引:9
介绍了环境影响评价中公众参与的发展和现状,论述了公众参与在环境影响评价中的地位作用,分析了我国环境影响评价中公众参与存在的问题,并从宏观法制保障、公众环境素质和技术操作程序三个层面提出了完善公众参与制度和提高公众参与有效性的对策. 相似文献
266.
土壤中污染物迁移模型在油田环境影响评价中的应用 总被引:6,自引:0,他引:6
在石油的生产、运输、贮存以及炼制等过程中都存在泄油、漏油风险,各生产过程中的废弃物,如油类、重金属等各种化学物质也会危害水土环境,进而危及当地地下水源。文章分析了油田企业污染物对土壤及地下水的主要污染途径,提出了将污染物在土壤中的迁移模型用于预测污染物浓度的方法。建立了污染物由土壤迁至室内空气、地下水、农作物及由地下水转移到地表水的迁移数学模型,该模型可以运用于油田环境影响评价。 相似文献
267.
John S. Richardson Robert J. Naiman Frederick J. Swanson David E. Hibbs 《Journal of the American Water Resources Association》2005,41(4):935-947
Riparian areas of large streams provide important habitat to many species and control many instream processes — but is the same true for the margins of small streams? This review considers riparian areas alongside small streams in forested, mountainous areas of the Pacific Northwest and asks if there are fundamental ecological differences from larger streams and from other regions and if there are consequences for management from any differences. In the moist forests along many small streams of the Pacific Northwest, the contrast between the streamside and upslope forest is not as strong as that found in drier regions. Small streams typically lack floodplains, and the riparian area is often constrained by the hillslope. Nevertheless, riparian‐associated organisms, some unique to headwater areas, are found along small streams. Disturbance of hillslopes and stream channels and microclimatic effects of streams on the riparian area provide great heterogeneity in processes and diversity of habitats. The tight coupling of the terrestrial riparian area with the aquatic system results from the closed canopy and high edge‐to‐area ratio for small streams. Riparian areas of the temperate, conifer dominated forests of the Pacific Northwest provide a unique environment. Forest management guidelines for small streams vary widely, and there has been little evaluation of the local or downstream consequences of forest practices along small streams. 相似文献
268.
JoAnn M. Hanowski Peter T. Walter Gerald J. Niemi 《Journal of the American Water Resources Association》2002,38(3):633-639
ABSTRACT: Forest buffers adjacent to water bodies are widely prescribed in forest management to protect ecological functions of riparian systems. To date, buffers have been applied on the landscape uniformly without quantifying their effectiveness or the effects they have on landscape characteristics. Our objective was to quantify landscape characteristics (amount of edge and interior forest) when buffers were applied to water bodies in a 100 by 100 km area of northern Minnesota. We used a Landsat classified image in a geographic information system platform to apply two buffer widths ?28.5 m and 57 m — to water bodies, including nonforested wetlands, intermittent or perennial streams, and lakes. A total of 107,141 ha (18.3 percent) of the forest area was adjacent to and within 28.5 m of these water bodies, while 201,457 ha of forest was within 57 m, representing 34.4 percent of the total forest area. Imposing a 28.5 m buffer on water bodies increased the amount of edge and interior forest in the study area. When water bodies were buffered with a 57 m forest strip, we found a slight increase in forest edge from the current condition, and this buffer width resulted in the largest amount of interior forest. Interior forest increased with the 57 m buffer due to the density of water bodies in this region; adjacent water bodies coalesced when buffers were applied and formed isolated forest islands that contained forest interior habitat. Instead of wholesale application of set width riparian buffers, we suggest that ecological conditions of riparian areas be evaluated on a site level and that areas that currently provide important riparian conditions be maintained on the landscape with appropriate management practices. 相似文献
269.
SARS疫情的标度性质及其物理意义 总被引:1,自引:0,他引:1
吴忠良 《防灾减灾工程学报》2003,23(2):10-13
使用Zipf分布研究了2003年4月20日前后中国内地各省的SARS疫情,发现SARS病例数满足分段的幂律关系,其中不同的段分别相应于不同的传播方式。资料显示,4月20日前后北京地区处于非常特殊的状态,此时所采取的非常措施看来是十分必要的。 相似文献
270.
Jonathan W. Long Aregai Tecle Benrita M. Burnette 《Journal of the American Water Resources Association》2003,39(6):1345-1359
ABSTRACT: To prioritize sites for riparian restoration, resource managers need to understand how recovery processes vary within landscapes. Complex relationships between watershed conditions and riparian development make it difficult to predict the outcomes of restoration treatments in the semiarid Southwest. Large floods in 1993 scoured riparian areas in the Carrizo watershed on the White Mountain Apache Reservation in east‐central Arizona. We evaluated recovery at three of these sites using repeated photographs and measurements of channel cross sections and stream‐side vegetation along permanent transects. The sites were mapped as lying on the same soil type, had similar streamside vegetative communities, and were similarly treated through livestock exclusion and supplemental seeding. However, the sites and individual reaches within the sites followed strikingly different development paths. Dramatic recovery occurred at a perennial reach where cover of emergent wetland plants increased from 4.7 percent (standard error = 0.8 percent) in October 1995 to 55.5 percent (standard error = 2.7 percent) in September 2001. At several other reaches, geologic and hydro geomorphic characteristics of the sites limited inputs of fine sediment or surface water, resulting in modest or negligible increases in emergent cover. Recovery efforts for highly valued marshlands in this region should prioritize perennial reaches in low gradient valleys where salty sediments are abundant. 相似文献