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1.
本文提出了适合于农村质量区划的分区方法,即首先以主成分分析法分析农村质量问题,然后以多种聚类分析法取得一个初始分区系统,最后用判别分析法判别该初始分区系统中各区域单元的类型归属是否正确,对一些类型归属不恰当的作适当调整,最终得到农村环境质量分区系统,文章最后讨论了类型划分问题。  相似文献   

2.
目前工业“三废”对农村环境污染的发展趋势有所减缓,但乡镇工业对农村环境污染的比重仍在逐渐增大,污染势头继续增强。从整体上讲,农村环境质量继续恶化的趋势尚未得到有效的控制。为加强农村环境质量的管理,本文着重论述了农村环境质量区划应遵循的4条原则,以层次分析法为原理,从自然生态环境、人类开发强度、环境状况3个方面,提出由28个指标组成的农村环境质量区划指标体系,该指标体系简便适用、易于操作,对不同层次、不同地区的具体区划具有指导意义。  相似文献   

3.
城市生态环境质量分区方法学研究   总被引:3,自引:0,他引:3  
城市生态环境质量是影响城市景观和居民身心健康的最重要的因素之一,环境质量分区是进行城市生态环境评价的基础性工作,是进行城市环境规划的重要依据之一。本文从环境质量分区的概念阐述入手,在分析传统分区方法的同时,提出城市环境质量分区的遥感技术法,证明遥感技术应用于城市环境质量分区,具有精度高,快速和省力的特点。  相似文献   

4.
中国海洋自然保护区功能分区模式及分类管理初探   总被引:1,自引:0,他引:1  
我斟海洋自然保护区目前正处于高速发展过程中,保护区已有的功能分区模式已不能满足保护区建设和管理工作的需要。本文通过对海洋自然保护区的功能分区的分析探讨,提出不同类型的保护区应采用不同的功能分区模式进行管理。另外,以中华白海豚自然保护区为例,在分析其功能分区和种群分布特点的基础上,提出了不设核心区模式。最后,提出在保护区高速发展的同时,应加强海洋自然保护区本身的研究,应加强保护区的分类及功能分区的研究。  相似文献   

5.
洮儿河流域农业生态地质环境研究   总被引:1,自引:0,他引:1  
系统分析了吉林西部洮儿河流域的农业生态地质环境特征,揭示了流域内影响农业可持续发展的五大农业生态地质环境问题;按照地质、地貌、自然资源状况、生态环境灾害、环境质量等综合要素对流域进行了环境分区;最后论述了流域内农业生态地质环境的演化过程和影响因素。  相似文献   

6.
南京市城市生态污染现状、成因分析及治理对策   总被引:1,自引:1,他引:0  
通过系统研究,定量分析了南京市1997-1999年水质污染,大气环境质量,酸雨等现状,进而系统探讨了该市城市化进程中出现的主要生态环境问题,并运用生态景观异性理论和方法,结合实际调查情况,对主要的生态污染致成原因进行了分析,最后提出了具体的南京市生态环境问题治理与实现地续发展的对策。  相似文献   

7.
天津市土壤中Cd、Hg、As、Pb、Cu、Zn、Ni环境标准制订   总被引:5,自引:0,他引:5  
依据天津市土壤环境背景值资料及元素浓度生态效应、土壤环境质量的功能分区与标准分级,根据天津市环境现状,制订出了4级土壤环境标准。  相似文献   

8.
根据中国可持续发展信息共享系统建设的要求,针对全国农村生态环境质量的信息特征,描述了“全国农村生态环境质量信息共享系统”的设计背景、系统总体结构、数据组织形式以及信息表达方式,并探讨了实现信息共享系统的结构化设计、系统网络的集成式服务模型、动态网页制作、元数据库构建、统计信息的空间化表达方法、空间统计分析和信息共享安全保障等信息共享的关键技术途径。  相似文献   

9.
为了弥补以往农村环境综合整治规划存在的一体化和系统化缺陷,构建了自上而下分层链接的系统规划方法框架,该框架总体上以城市总体规划和环境规划为顶层控制框架,其下分为县(市)域层次、乡镇域层次和行政村域层次3个层次。在顶层控制框架下,逐层控制可以克服规划上下层脱节、有效性降低的弊病,从而提高规划的整体性、系统性和有效性,为进一步推进农村环境综合整治、提升农村环境质量发挥积极的作用。农村环境综合整治规划的重点在于乡镇域层次和行政村域层次,其主要内容应包括:乡镇和行政村的农村饮用水水源地保护、农村生活污水和垃圾处理、畜禽养殖污染治理、水产养殖污染防治、历史遗留的农村工矿污染治理、农业面源污染和土壤污染防治、景观生态规划,以及其他与村庄环境质量改善密切相关的环境综合整治措施等。规划中应以乡镇为基本规划单元,规划实施要分期分批。为此,提出了乡镇类型划分及分期分批整治原则,为农村环境综合整治规划提供指导。  相似文献   

10.
本文根据霍县区域环境质量评价的结果,探讨了各种污染源治理方案,从经济—环境协凋的原理,根据上游水质条件的变化,确定与地方经济发展相协调的环境质量目标,提出相应的分期、分级和分区治理的优选方案。本文以综合水质指数为环境质量目标,以年综合费用为经济目标,探讨了区域水污染控制策略,是污染控制规划的决策分析尝试。  相似文献   

11.
Functional zoning for air quality   总被引:2,自引:0,他引:2  
Environmental local agencies have to enforce European directives that impose a land classification, according to air quality status, to distinguish zones needing further actions from those needing only maintenance. This paper presents a land classification in zones featured by different criticality levels of atmospheric pollution, considering pollutant time series as functional data: we call this proposal “Functional Zoning”. Our proposal is articulated in order to also meet two specific requirements: upscaling pollutant concentration data to the municipality scale, since municipalities are the reference territorial administrative units for undertaking actions; aggregating different pollutants in order to provide a multi-pollutant zoning outcome reflecting the air quality status. Specifically, we present three different alternatives to upscale data from a regular grid to the municipality scale. Then, to aggregate by pollutant, we evaluate two strategies summarizing time series: the assessment of an air quality index and the use of the Multivariate Functional Principal Component Analysis (MFPCA). The partition of municipalities is obtained by clustering air quality time series and MFPCA scores. In particular, the proposed functional zoning is carried out for Piemonte (Northern Italy), considering the hourly concentration fields of the main pollutants. We obtain six classifications of the same land and we propose a comparison study of the different strategies’ results, by mapping and analyzing the differences between clusters’ labels. By taking into account the comparison study’s findings, we finally suggest an analysis strategy to environmental agencies and policy makers to obtain an easily interpretable outcome at a very reasonable computational cost.  相似文献   

12.
Complexity and uncertainty play important roles in coastal management. Economic development may push the coastal system beyond its resilience thresholds as a result of interactions between environmental and socio-economic processes. The concepts in this paper link processes of system change, natural evolutionary processes observed in coastal zones, to processes of social evolution. An indicator based on calculating an ecological footprint for coastal zones is presented to guide decision-making in spatial and economic planning. The suggested indicator may support a range of methods linking economic valuation and environmental impact analysis.  相似文献   

13.
The self-thinning line is a very robust pattern, which can be obtained in modeling studies by a variety of different mechanistic assumptions. Our opinion is that we can only advance in our understanding of mechanisms leading to the self-thinning relationship if we demand that the model also reproduces several other characteristic features (patterns) of the self-thinning process such as the degree of size inequality and the average size. We use a pattern-oriented modeling approach to develop a model of self-thinning under size inequality in overcrowded, even-aged stands, which reproduces these three patterns simultaneously. Our approach is to first develop an initial model based on our current ecological knowledge and then to refine the model by modifying the initial model to derive the model that reproduces all patterns of interest.The initial model is as simple as possible while avoiding incidental, ecologically unjustified, assumptions. It is a further development of zone of influence-simulation models: each plant is described by two circles, one describing a minimum-domain-area and one describing the zone of influence. In the initial model, mortality is “death-by-contact” of minimum-domain-areas and growth is a function of inter-tree competition, i.e. overlapping zones of influence. Model parameterization is based on field data on Acacia reficiens in southern Africa. Simulations follow patches of initially small trees through time for up to 1000 years with five parameters, three describing growth and two describing inter-tree competition. A sensitivity analysis shows that all parameters of the initial model contribute significantly to the number and size of plants through time. The two competition parameters, which describe competitive asymmetry and the size of the zone of influence relative to canopy size, are both important for generating size inequality. Thus, both competitive asymmetry and spatial pattern contribute to size inequality, and their relative importance may vary greatly.The sensitivity analysis suggests that all processes included in the initial model are essential to the evolution of size inequality. However, size inequality under the initial model is below field values, meaning that additional, as yet unconsidered processes, contribute to size inequality. Our best-fit model additionally contains details on growth stochasticity.This study establishes the often-proposed direct link between mortality driven by local competition and self-thinning and highlights the importance of stochasticity in ecological processes.  相似文献   

14.
天津市生态环境建设展望   总被引:1,自引:0,他引:1  
本文紧密结合天津市生态环境的特点,坚持污染防治与生态环境保护并重的方针,优先抓好重点区域和重点工程,突出重点,分步实施,从天津市四个生态功能区入手,明确生态环境建设的主攻方向,即:(1)新建和完善天津市各级各类自然保护区;(2)在城市生态区规划建设城市生态环境圈;(3)以蓟北山区为代表,建设生态示范县;(4)中部平原区实行生态农业建设与开发;(5)东部滨海地区生态恢复与建立沿海生态经济型防护林体系  相似文献   

15.
城市生态信息系统的开发与实施   总被引:2,自引:1,他引:2  
本文提出了城市生态信息系统开发研制模式,探讨了系统设计与实施的基本步骤,对系统分析、系统规划、初步设计、详细设计和系统实施等主要应用系统开发环节作了详细的论述,并根据国内空间信息系统的发展趋势,提出了系统软、硬件的配置要求。  相似文献   

16.
Exploration and development of oil and gas (O&G) energy resources can create large-scale and permanent landscape effects that are best measured and understood via fieldwork and geospatial technologies. In this article, we examine O&G surface disturbance in the Orenburg steppe region of southwestern Russia for the year 2015. Utilizing field surveys, remote-sensing data and geographic information system (GIS) techniques, we apply a two-pronged approach. First, we map and measure the landscape infrastructure footprint (LIF) to determine the pattern and extent of direct surface disturbance created by O&G facilities and access roads. Second, we conduct a site suitability analysis to identify specific O&G production locations that are most vulnerable to environmental degradation. The approach considers both the particular properties of hydrocarbon production and specific natural features of steppe zones. Suitability patterns represent three indicators: two morphometric parameters (slope and aspect) and one spatial (the remoteness of O&G objects from water bodies). Our findings suggest that O&G production disturbs just over 3% of soil-vegetation cover in our study plot, while more than 13% of O&G objects are located in unsuitable zones based on topographic aspect, and about 11% lie in unsuitable zones regarding distance to water.  相似文献   

17.
Coastal zones in Portugal, as interface areas between land and sea, have problems related to the growing human pressure in terms of changes in land use associated with urban and industrial occupation, new accessibility (ports, motorways) and traffic flows, intensification of recreational use (beaches, water sports) and excessive fishing. Impacts include deterioration of water quality and sediments; alteration and degradation of natural habitats; new hydrodynamic situations; major landscape changes: and rapid changes in habits and way of life of the local populations and increased exposure of populations and assets to natural and induced risks (storms, accidents, spills, explosions). Plans for the Management of the Coastal Zone (POOC) have been developed and seven of them have been approved, while two similar plans are at a final stage of preparation. Together they cover the entire coast of Portugal. Their implementation and assessment could be a first step towards an integrated management of the Portuguese coastal zones. River Basin Management Plans (PBH) have been concluded and recently approved for the whole country. However, these plans do not consider estuarine systems and some other issues related to coastal systems. The National Water Plan (PNA) is under public presentation and discussion. Several ‘key messages’ are presented in this paper as a contribution for assessment of the proposals of this plan on issues related with coastal waters.  相似文献   

18.
This paper investigates the effect of low emission zones on air quality and birth outcomes in Germany. The staggered introduction of the policy measure creates a credible natural experiment and a natural control group for births and air pollution measurements in cities that enact low emission zones. I show that the introduction of the most restrictive type of low emission zone decreases average levels of fine particulate matter by about 4 percent and by up to 8 percent at a city's highest-polluting monitor. Low emission zones also reduce the number of days per year on which legal pollution limits are exceeded by three. However, these reductions are too small to translate into substantial improvements in infant health. My results are not driven by changes in maternal or city specific characteristics, and are robust to variations in specification and to the choice of control group.  相似文献   

19.
This paper examines existing measures taken to protect the coastal zones of the Mediterranean Sea and assesses their success. A summary of the main pressures facing this region is given, followed by an analysis of the legislation covering coastal zone development in ten countries: Algeria, Croatia, Egypt, France, Israel, Italy, Malta, Spain, Tunisia and Turkey. The paper finds that not all of these States have legislation specifically covering coastal zones, but there is concern in all areas that existing legislation is not working. The costs and benefits of controlling coastal development are examined. Firstly, a literature review of valuation studies identifies a range of values placed on the developed and undeveloped coastline for both users and local property owners. These values were then used in a model to evaluate policy options to control development of a stretch of coastline. The model indicates that a stricter control regime of coastal development may provide significant benefits.
A. MarkandyaEmail:
  相似文献   

20.
《Ecological modelling》2003,170(2-3):245
With the increasing importance and awareness of water quality in the small basins, the modelling system is developed for monitoring and predictions of surface water pollution. The compartment model deals with basin characteristics extended by land cover attributes. The parameters of the model are estimated by experimental data of water quality together with land cover types that serve as nutrient detention media or transformers. The study examines methodology to determine the potential areas of nitrate pollution from point and non-point sources by remote sensing techniques. Classification of water, agricultural, forest and urban areas is processed with satellite images (LANDSAT 7). Whereas the agricultural and urban areas act as sources of pollution, forest zones operate as sinks. The nitrate levels are decreased downstream, if the proportion of the forest inside contribution zones increases. The modelling system is used to simulate amounts of nitrates in each compartment of the stream during the monitored period of one year. The number of compartments and their lengths are estimated on the basis of morphology of the basin. Simulation of the dynamic model is carried out with the TabSim. Geographic information system (GIS) and remote sensing tools are used to manage and estimate nitrate inflows from point and non-point sources of pollution. The article presents the spatial and time variation of the nitrate (NO3) within the basin of the stream Rakovnický (the west part of Bohemia, the whole area of 368 km2). It is shown that the model approach extended by the GIS and remote sensing can support decision-making process for better management practices in the basins.  相似文献   

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