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21.
Local Biodiversity Action Plans are the preferred policy mechanism for setting and delivering local biodiversity targets in the UK. This paper reviews the kind of knowledge conservation scientists envisage being used to identify and set local targets, and explores the means of incorporating local knowledge into this process. We use a case study of a Wildlife Enhancement Scheme (WES) on the Pevensey Levels, East Sussex, to reveal the understandings that local farmers and residents have of the nature conservation goals and practices associated with the scheme. Drawing on the findings of in-depth discussion groups, we show how farmers challenge both the monopoly of knowledge conservationists profess about nature, and the enlistment of farmers on the scheme as «technicians», motivated solely by financial rewards, rather than as knowledgeable experts who also have emotional attachments and ethical values for nature. Local people use their knowledge of both local farmers, and the industry in general, to challenge the assumption that farmers can be trusted with delivering nature conservation goals. In the absence of a commitment by central government to agree widely-held environmental standards, and a more democratic process of making judgements about what local nature is worth conserving, local residents challenge existing processes designed to conserve nature that are driven by the knowledge and practices of official experts alone. The findings of the study suggest that a widening of the knowledge base on which the goals and practices of nature conservation are founded, and a more deliberative process of making decisions about what nature is important locally, will secure and strengthen public support for local biodiversity action plans.1998 Academic Press  相似文献   
22.
ABSTRACT

The Norwegian urban growth agreement (UGA) is a governance platform combining transport-infrastructure development with land-use and transport policy. It is a policy package of measures involving network cooperation between national, regional and local government levels established to coordinate transport and land-use development. Shared responsibility for goal achievement, autonomy and learning and adaptation as new knowledge and experience arise are clear prerequisites for the UGAs. This makes it relevant to investigate the conditions for the UGAs to work as an adaptive governance strategy because their central features are in line with the attributes of adaptive governance. Further, adaptive governance is an approach to handle complex problems like transport development issues. The study shows that UGAs have several strengths in terms of autonomy and learning. However, the multi-level cooperation in the UGAs is framed by complex underlying structures of roles and powers, which challenge the working and legitimacy of the governance structures. Multi-level adaptive governance processes like the UGAs require attention to issues of power and legitimacy. Securing transparency and democratic anchorage is paramount in bringing such processes in line with the intended benefits of adaptive governance.  相似文献   
23.
The Town Scheme approach to urban conservation is being used increasingly as a major method of repairing historic buildings in conservation areas. A Town Scheme involves a long‐term financial and administrative partnership between the various levels of government. An annual budget made up of equal contributions from central government and the participating local authority is used to finance a multi‐year programme of repairs. Owners can apply for grants which are usually for 40 per cent of approved costs, and repair work must relate to the original structure and architectural details of an approved list of historic buildings. Town Schemes by themselves cannot totally transform the environmental quality of conservation areas, and the most successful schemes are part of wide‐ranging renewal and enhancement projects.  相似文献   
24.
以宁波市甬江流域为例,以GIS技术辅助流域水污染控制规划,在ARCGIS90的环境中,完成了流域水系概化、水质评价,并利用GIS的叠置技术,建立功能区划水域-入河排污口-陆上汇流区的对应关系。根据水环境功能区的水质目标,通过建立污染源-水环境质量的输入响应关系,然后利用GIS技术对甬江流域数字高程模型(DEM)进行数字地形分析,得到甬江流域的模拟河网和流域汇水图,构筑了水污染控制单元,作为水环境容量核定和总量分配的基本工作区域。最后利用GIS的可视化表达进行辅助决策,确定各水环境功能区的水环境容量,结合排污状况(包括工业、农业、生活)的分析,得出流域水污染控制的总量控制方案和对策措施。甬江流域水污染控制规划的实践表明,在规划过程中,GIS作为一个必不可少的工具渗透在每一个环节中,为数据管理、空间图形表达和空间决策分析提供有效的工作平台和可靠的技术支持  相似文献   
25.
气候变化是当今世界关注的全球性问题。在总结国际上各主要利益集团的减排方案和对策的基础上,根据国际和国内专家的理解并结合中国国情,首先选出适合中国的经济政策和技术政策;在此基础上,运用层次分析法分析这些对策,确定其可行性和优先顺序,提出适合中国的减排对策方案建议。  相似文献   
26.
采用WRF-Chem模式中的3种边界层方案YSU、MYJ和ACM2对2019年6月京津冀及周边地区典型O3污染月份开展模拟研究.详细对比了各方案对地面气象要素、NO2和O3浓度时空分布,以及温湿风要素和O3浓度垂直分布的模拟效果.结果表明:3种方案对地面气象要素的时空分布和温湿风要素的垂直变化模拟较为合理.MYJ方案模拟地面气象要素整体效果最佳.各方案对边界层高度的日变化特征模拟较好,相关系数为0.58~0.69,但存在白天偏高、夜间偏低的现象,YSU方案相比效果最佳.3种边界层方案对NO2浓度模拟普遍高估,而O3模拟结果则出现低估.白天模拟偏差较小而夜间偏差较显著.模拟最佳的是ACM2,其次为YSU和MYJ.3种方案均较好地模拟出了O3的垂直分布特征,但整体低估了O3浓度.对上午O3垂直分布的模拟差异较下午更为明显.此外,基于YSU方案设置了3个敏感实验,通过调整化学模块所用的湍流扩散系数阈值,对比分析了垂直混合过程改变对O3浓度模拟的影响,模拟的变化只反映由于边界层的垂直混合过程改变造成的污染差异,而不是由于热动力场的调整造成的变化.模拟结果表明3个方案均可改善区域上地面NO2和O3的模拟性能,尤其是对原3种边界层方案模拟O3均明显低估的华北平原地区提升效果最显著,平均偏差降低了23.7%.在垂直方向上,湍流扩散系数阈值的调整增加了早间近地面模拟的O3浓度,改善了模拟偏低的现象,但同时增大了高层O3浓度的负偏差.敏感性方案显著改善了夜间的模拟,白天则并不明显.这些结果显示出湍流扩散系数对O3垂直混合的重要影响.因此,改进湍流扩散系数的参数化对O3模拟是必要的.  相似文献   
27.
为解决石油化工园区目前以标准规范规定的距离进行区域规划存在的局限性,提出基于风险进行石油化工园区安全规划的技术思路;研究、建立石油化工园区定量风险评估和区域规划技术方案,包括:危险源的辨识、评估单元选择、事故类型筛选、不同目标的风险标准、园区累积风险计算和基于风险进行区域规划的基本原则;应用建立的定量风险评估区域规划技术方案,对一石油化工园区光气及光气化产品项目进行定量风险评估、区域规划和布局,并与目前执行的距离标准进行对比分析。基于风险的石油化工园区安全规划,综合考虑危险源的危险特性和不同目标的风险承受能力,较之于距离法具有更强的针对性。  相似文献   
28.
Gaussian-based dispersion models are widely used to estimate local pollution levels. The accuracy of such models depends on stability classification schemes as well as plume rise equations. A general plume dispersion model (GPDM) for a point source emission, based on Gaussian plume dispersion equation, was developed. The program complex was developed using Java and Visual basic tools. It has the flexibility of using five kinds of stability classification schemes, i.e., Lapse Rate, Pasquill–Gifford (PG), Turner, σ–θ and Richardson number. It also has the option of using two types of plume rise formulations – Briggs and Holland’s. The model, applicable for both rural and urban roughness conditions, uses meteorological and emission data as its input parameters, and calculates concentrations of pollutant at the center of each cell in a predefined grid area with respect to the given source location. Its performance was tested by comparing with 4-h average field data of continuous releases of SO2 from Dadri thermal power plant (Uttar Pradesh, India). Results showed that the Turner scheme used with Holland’s equation gives the best outcome having a degree of agreement (d) of 0.522.  相似文献   
29.
杨景朝  蒋兴文  伯鑫  王刚  冯勇 《环境科学》2023,44(1):104-117
精准的气象场和适用的空气质量模式是优化大气污染模拟的重要途径.为提升四川盆地冬季大气污染模拟效果,利用WRF模式25组参数化方案组合,进行气象场模拟试验,基于最优方案数据,以四川盆地某大型钢铁厂为例,分别驱动AERMOD模式和CALPUFF模式,通过研究区域4个国控站数据对模拟结果进行对比验证.结果表明,WRF模式参数化方案选取对地面风场、高空风场和地面湿度场模拟效果影响较大,对地面温度场、高空温度场和高空湿度场模拟效果影响较小,SLAB陆面过程方案、 Dudhia短波辐射方案分别与YSU、 ACM2、 BouLac和MRF边界层方案的组合,均能较好地模拟四川盆地冬季地面风场、温度场和湿度场的变化趋势,结合高空风温湿统计参数综合分析可知,第1组方案适用于达州气象场模拟,第13组和第17组方案分别适用于成都白天和夜间时段气象场模拟.CALPUFF模拟结果与监测值的相关性整体优于AERMOD,从站点角度分析,CALPUFF在国控站3号的模拟效果相较AERMOD提升较大,在国控站2号的模拟效果提升较小,从大气污染物角度分析,4个国控站CALPUFF对NOx和PM  相似文献   
30.
Europe is a region of relatively high population density and productive agriculture subject to substantial government intervention under the Common Agricultural Policy (CAP). Many habitats and species of high conservation interest have been created by the maintenance of agricultural practices over long periods. These practices are often no longer profitable, and nature conservation initiatives require government support to cover the cost for them to be continued. The CAP has been reformed both to reduce production of agricultural commodities at costs in excess of world prices and to establish incentives for landholders to adopt voluntary conservation measures. A separate nature conservation policy has established an extensive series of protected sites (Natura 2000) that has, as yet, failed to halt the loss of biodiversity. Additional broader scale approaches have been advocated for conservation in the wider landscape matrix, including the alignment of agricultural and nature conservation policies, which remains a challenge. Possibilities for alignment include further shifting of funds from general support for farmers toward targeted payments for biodiversity goals at larger scales and adoption of an ecosystem approach. The European response to the competing demands for land resources may offer lessons globally as demands on rural land increase.  相似文献   
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