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331.
差异性区域网格化环境管理是在环境状况存在明显分异区域进行环境管理的有效的方式。依托网格化管理在资源整合和信息共事方面的优势.探讨在环境状况差异明显区域构建网格化管理体系的目标、步骤与管理思路。以上海市宝山区的实践为例.根据区内环境现状差异明显的特征。将全区划分为150个网格.从中选取环境矛盾较为突出的网格.开展区域环境综合整治与环境建设.逐年逐块提升区域网格环境状况.实现区域环境网格等级的提升.初步达成区域生态、生产、生活的协调。实践表明.差异性区域网格化管理是建设环境友好型社会的一种有效的环境管理手段。 相似文献
332.
用于评价水污染的生物指数 总被引:13,自引:0,他引:13
对各国学者所建立的应用较广泛的生物指数作了综述 ,通过分析各种生物指数的优点与缺陷 ,指出了目前建立生物指数方法上的不足 ,并提出了建立生物指数应该采用的更合理的方法。 相似文献
333.
Abstract: The effectiveness of rare plant conservation will increase when life history, demographic, and genetic data are considered simultaneously. Inbreeding depression is a widely recognized genetic concern in rare plant conservation, and the mixing of genetically diverse populations in restoration efforts is a common remedy. Nevertheless, if populations with unrecognized intraspecific chromosome variation are crossed, progeny fitness losses will range from partial to complete sterility, and reintroductions and population augmentation of rare plants may fail. To assess the current state of cytological knowledge of threatened and endangered plants in the continental United States, we searched available resources for chromosome counts. We also reviewed recovery plans to discern whether recovery criteria potentially place listed species at risk by requiring reintroductions or population augmentation in the absence of cytological information. Over half the plants lacked a chromosome count, and when a taxon did have a count it generally originated from a sampling intensity too limited to detect intraspecific chromosome variation. Despite limited past cytological sampling, we found 11 plants with documented intraspecific cytological variation, while 8 others were ambiguous for intraspecific chromosome variation. Nevertheless, only one recovery plan addressed the chromosome differences. Inadequate within‐species cytological characterization, incomplete sampling among listed taxa, and the prevalence of interspecific and intraspecific chromosome variation in listed genera, suggests that other rare plants are likely to have intraspecific chromosome variation. Nearly 90% of all recovery plans called for reintroductions or population augmentation as part of recovery criteria despite the dearth of cytological knowledge. We recommend screening rare plants for intraspecific chromosome variation before reintroductions or population augmentation projects are undertaken to safeguard against inadvertent mixtures of incompatible cytotypes. 相似文献
334.
This paper aims to identify the main driving force for changes of total primary energy consumption in Beijing during the period of 1981-2005. Sectoral energy use was investigated when regional economic structure changed significantly. The changes of total primary energy consumption in Beijing are decomposed into production effects, structural effects and intensity effects using the additive version of the logarithmic mean Divisia index (LMDI) method. Aggregate decomposition analysis showed that the major contributor of total effect was made by the production effect followed by the intensity effect, and the structural effect was relatively insignificant. The total and production effects were all positive. In contrast, the structural effect and intensity effect were all negative. Sectoral decomposition investigation indicated that the most effective way to slow down the growth rate of total primary energy consumption (TPEC) was to reduce the production of the energy-intensive industrial sectors and improving industrial energy intensity. The results show that in this period, Beijing's economy has undergone a transformation from an industrial to a service economy. However, the structures of sectoral energy use have not been changed yet, and energy demand should be increasing until the energy-intensive industrial production to be reduced and energy intensity of the region reaches a peak. As sequence energy consumption data of sub-sectors are not available, only the fundamental three sectors are considered: agriculture, industry and service. However, further decomposition into secondary and tertiary sectors is definitely needed for detailed investigations. 相似文献
335.
中国县域资源组合结构的分类研究 总被引:7,自引:0,他引:7
按区域经济的发展,遵循资源分布的地域分异规律,论述了中国县域资源的地域组合结构的分类问题。首先对采用多因素综合作用、自然资源与经济资源兼容组合、资源优势、资源系统良性循环等原则进行了必要性的论证;在此基础上重点对其分类方法进行了具体说明,其主要步骤是在确定10种主要的县域资源,建立相关在指标体系的前提下,鉴于威弗组合指数对于划分县域资源组合结构类型的可行性,运用改造过的,角立县域资源地域组合结构类型的划分程序与计算方法。最后,按此分类法,把我国县域资源地域组合结构类型划分为自然资源型、自然资源主导型、自然资源与经济资源混合型、经济资源主导型、经济资源密集类等5个一级类型及其下属的8个二级类型。 相似文献
336.
《环境科学学报(英文版)》2023,35(4):483-493
When exposed to different relative humidities (RHs), the optical properties of atmospheric aerosols will change because of changes in the aerosol particle size and complex refractive index (RI), which will affect haze formation and global climate change. The potential contributions of ultrafine particles to the atmospheric optical characteristics and to haze spreading cannot be ignored because of their high particle number concentrations and strong diffusibility; measurement of the optical properties of wet ultrafine particles is thus highly important for environmental assessment. Therefore, a surface plasmon resonance microscopy with azimuthal rotation illumination (SPRM-ARI) system is designed to determine the RIs of single particle aerosols with diameters of less than 100 nm in the hygroscopic growth process. Measurements are taken using mixed single particles with different mass ratios. The RIs of mixed single aerosols at different RHs are retrieved by measuring the scattering light intensity using the SPRM-ARI system and almost all the RIs of the bicomponent particles with different mass ratios decrease with increasing water content under high RH conditions. Finally, for each of the bicomponent particles, the maximum standard deviations for the retrieved RI values are only , and , corresponding to the NaCl and NaNO3 bicomponent particles with a 3:1 mass ratio at 76.0% RH, the NaCl and glucose particles with a 1:3 mass ratio at 89.0% RH, and the NaCl and OA particles with a 1:1 mass ratio at 78.0% RH, respectively; these results indicate that the high-sensitivity SPRM-ARI system can measure the RI effectively and accurately. 相似文献
337.
The application of ecological concepts to the industrial setting has been touched upon by literature across several disciplines. Two emerging ecological planning approaches, landscape ecology and industrial ecology, are applied here to look at alternative ways of planning industrial parks. As an emerging field, landscape ecology provides different viewpoints from the traditional approach of natural conservation, which mainly focuses on the protection of nature. The approach of landscape ecology regards the environment as a land mosaic, a mixture of natural and urban environment, which concerns a manageable human-scale environment across one or two human generations. Industrial ecology, on the other hand, goes beyond the traditional “end of pipe” idea of pollution control and learns from the ecosystem concept. The current paper is an attempt to reconcile these two fields as an integrated approach to the planning of industrial areas. Using a case study of Singapore’s Jurong Island industrial park, two fundamental issues behind the idea of landscape ecology and industrial ecology are raised. If raw materials, energy and by-products are more easily replaced or reused by technology and management, then research on industrial ecology and related knowledge will be crucial for developing natural resource substitution by innovative technology and new ways of environmental management. Where it is difficult to substitute natural resources, the skills of planning and managing natural resources will take priority over other strategies. In this situation, the knowledge of landscape ecology needs to be applied to the prediction, design and evaluation of ecologically optimum resource uses, patterns and processes in the mixture of natural, urban and industrial environment. A new concept, “nurtured landscape”, is proposed for mediating between the natural ecosystem and the urban/industrial environment. The nurtured landscape provides a basis for the development of new ecological technology using landscape to ameliorate the polluting effects of the urban/industrial neighbourhood. The planning of Singapore’s Jurong Island industrial park provides a test of applying the principles of landscape ecology and industrial ecology to the possible transformation of an industrial area. 相似文献
338.
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340.
以遥感影像数据、专题数据、DEM数据、气象站实测数据和统计数据为数据源,采用极差法、层次分析法、综合指数法、RS&GIS等方法对长白山地区的生态安全进行了评价.结果表明:长白山地区生态安全水平呈现出明显的空间差异性,整体由中部向东西两端逐渐降低.各生态安全等级面积从大到小为临界安全等级、较安全等级、不安全等级、较不安全等级、安全等级.统计了各行政单元的平均生态安全指数和等级构成,各县市生态安全水平从高到低为长白县、抚松县、安图县、和龙市、临江市,各县市的生态安全等级构成也有所差异.长白山地区生态安全水平以临界安全等级为主,整体上生态环境质量一般,系统服务功能受到了一定程度的破坏. 相似文献