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1.
准确客观评估区域水环境风险是预防区域突发性污染事故、保证区域水环境安全的基础。基于欧盟Seveso Ⅲ指令,综合考虑风险源管理水平和泄漏风险、污染迁移时间、风险受体脆弱性等重要因素,对指令模型进行优化完善,构建基于欧盟Seveso Ⅲ指令的区域环境风险评估方法,并应用于北江流域,评估流域内各工业企业固定点源及典型非点源对饮用水水源等受体的区域环境风险。评估结果显示:北江三水思贤滘以上流域划分的46个子区域中存在7个风险区,其中高风险区主要分布在北江干流韶关段,中风险区主要分布在北江干流清远段和肇庆段,评估结果与流域风险分布基本吻合。建议根据评估风险值对北江流域开展分级风险管控。  相似文献   

2.
生态风险评价研究进展综述   总被引:5,自引:0,他引:5  
在介绍生态风险评价意义的基础上,简要回顾了国外生态风险评价研究的发展历程,着重论述了现阶段国内生态风险评价的重点研究领域,包括生态风险评价指标体系建立与评价标准确定的探讨、水环境化学生态风险评价、区域生态风险评价、景观生态风险评价、流域生态风险评价,以及"3S"技术在生态风险评价中的应用。归纳了生态风险评价的方法学和评价模型的选择等重要技术手段,并针对目前存在的问题及薄弱环节,提出了未来研究的发展趋势和需要解决的关键问题。  相似文献   

3.
将农业面源污染风险区划入生态保护红线中,防范由此导致的饮用水水源富营养化现象,是值得深入探讨的科学问题。以南水北调中线重要水源地丹江口水库流域十堰段为例,基于农业面源污染风险区的识别,通过情景分析探讨生态保护红线优化方法,改善区域生态环境,推动绿色发展。结果表明:将农业面源污染极高风险区划入生态保护红线,区域氮、磷流失削减率可分别达35.9%和26.33%,在一定程度上增强了生态系统连通性,且人口生态压力指数较小(0.23),可统筹生态效益和经济效益的发展。研究结果有望为存在农业面源污染风险的丘陵山区提供一种红线优化新思路。  相似文献   

4.
采用Hakonson生态风险指数法对京杭运河苏州段近十年来底泥重金属污染进行评价,对其空间分布和时间分布规律进行了分析。结果表明,京杭运河苏州段重金属为低生态风险等级,汞和镉为主要的生态风险因子,城区老运河段重金属生态风险指数最高。近十年来,京杭运河苏州段底泥重金属潜在生态风险指数呈下降趋势,重金属污染得到有效的控制。  相似文献   

5.
监测分析了以揭西县林地、农业用地和建设用地的331个土壤样品中的重金属含量,运用潜在生态风险指数法、健康风险指数法以及克里金插值法等对镍、锌、汞、砷、铜、镉、铅和铬的潜在生态风险和潜在健康风险进行研究。结果表明:汞超出《土壤破坏质量 农用地土壤污染风险管控标准》风险筛选值,存在一定风险。研究区具有轻微潜在生态风险,汞和镉是主要生态风险因子,高值区主要分布在建设用地,综合潜在生态风险高值区主要分布在建设用地。成人和儿童的单项非致癌风险指数总和(HQ)和总非致癌风险指数(HI)均<1,非致癌风险在可接受范围内。铬、砷和铅是主要非致癌贡献因子。砷对成人和儿童具有较高的致癌风险,是主要致癌风险因子。不同土地利用类型下成人和儿童总致癌风险指数(TCR)依次为农业用地>林地>建设用地。单项致癌风险指数总和(CR)均为砷>镉>铬。  相似文献   

6.
干旱区内陆艾比湖流域平原区景观生态安全评价研究   总被引:1,自引:0,他引:1  
在构建基于景观尺度的生态安全评价模型基础上,分析了1990-2005年干旱区内陆艾比湖流域平原区的景观生态安全变化特征。结果表明:研究区景观生态安全状况可以分为3个层次,并以河流、湖泊及沼泽为主的湿地景观所在区域的生态安全程度相对较高。1990-2005年,研究区生态安全状况呈现"V"字型变化趋势,其中生态安全评价指数相对较低区域的面积所占比例呈现先增加后减少、总体上趋于增加的状态;而生态安全指数相对较高区域的面积所占比例呈现先减少后增加、总体上趋于减少的状态。  相似文献   

7.
根据滇池外海主要入湖河口及重点区域底泥疏浚工程,宝丰湾疏浚区设计阶段勘察结果,采用内梅罗污染指数法及Lars Hakanson的重金属潜在生态风险指数法对疏浚区底泥进行了污染程度评价。针对底泥污染空间分布特征,确定疏浚深度,为环保施工提供依据。  相似文献   

8.
艾比湖流域核心区景观生态功能区划及生态调控措施研究   总被引:1,自引:0,他引:1  
在探讨了景观生态功能区划的概念、原则及区划方法的基础上,以新疆艾比湖流域核心区为对象,采用叠置法并利用“3S”技术对研究区进行了自下而上的景观生态功能区的划分,共划分出4个景观生态功能区和9个景观生态功能亚区。分析了各景观功能区的主导生态功能、保护目标,并有针对性地提出了景观生态调控的工程措施和管理措施,为恢复和重建艾比湖流域景观生态安全格局提供科学的参考依据。  相似文献   

9.
从码头主体风险和风险控制机制2个准则出发,构建了码头源风险评价指标体系和风险评价方法,提出,采用风险分布密集指数和码头源数量指数,反映港区内码头风险分布密集程度和码头数量对港区风险的影响程度。以码头风险评价方法为基础,综合考虑港区码头源风险大小、风险分布密集指数、码头源数量指数,建立了考虑风险分布密集型的港区风险评价方法。应用该方法对南京市龙潭港区进行风险评价,结果表明,南京市龙潭港区风险等级为高风险,港区内高风险码头共7座,且主要集中分布于南京长江四桥附近约2 km岸线内。  相似文献   

10.
通过在丰水期对贵州省某流域城市河段悬浮物和沉积物中的重金属含量进行测定,运用单因子指数法、生态风险评价法、因子分析法,初步探讨了该河段Cu、Zn、Pb、Hg、Cd、Cr、Ni及As等8种重金属元素的含量分布、污染特征、潜在生态风险及主要来源。检测结果显示,沉积物和悬浮物中Hg、Cd、Zn、Pb、As的平均含量较高,是贵州省土壤背景值的1.02~16.97倍。单因子指数评价结果表明:在沉积物中,Zn、Pb、As为轻度污染,Hg和Cd为重度污染;在悬浮物中,Cu、Pb、As为轻度污染,Zn为中度污染,Hg和Cd为重度污染。潜在生态风险指数评价结果显示,Hg和Cd的生态风险最大,为主要污染元素。研究区沉积物样品综合生态风险指数(RI)介于183.27~1 393.96,平均值为912.06,总体处于严重生态风险等级;悬浮物样品RI值介于341.53~612.38,平均值为436.85,总体处于重度生态风险等级。其中,沉积物样品重金属平均生态风险等级高于悬浮物样品,支流样品重金属生态风险等级总体上低于干流下游样品。根据因子分析法分析结果,初步推测沉积物及悬浮物Hg、Cd、Cr、Ni含量主要受工...  相似文献   

11.
As an important component of sustainable development in mountain areas, evaluation for sustainable land use is always one of the hotpots of researches on sustainable development. Traditional evaluation for sustainable land use mainly focuses on the sustainability of land use model and biological production on temporal scale, and overlooks the effects of land use patterns on the sustainability, while landscape ecology can be a good help to realize the spatial analysis of sustainable land use. In this study, a synthetic evaluation indexes system for sustainable land use was constructed through the application of landscape metrics. Taking Yongsheng County of Yunnan Province, China as a case study, a series of quantitative evaluation were conducted in 1996, 1999 and 2001, to monitor the temporal dynamics of regional land use sustainability. Two indicators, contributing amount of indexes, and obstacle amount of indexes, were also set up to ascertain the significance of all the evaluation indexes to the evaluation results. The results showed that, in the study phases, the land use sustainability of the whole county had been low with a stable but great spatial difference, and great changes took place in regional land use system in 1999 with the deviation from the aim of sustainable land use. It also showed that, the most important indexes contributing for the land use sustainability in the study period, were the indexes of population density and land use degree, followed by the index of landscape diversity and cropping index. And the most important indexes counteracting the land use sustainability were the indexes of per unit area total production value of industry and agriculture, per unit area yield of cereal crops, landscape fragmentation, followed by the indexes of per unit area yield of economic crops and fertilizer consume per unit area.  相似文献   

12.
Using land use and cover change (LUCC) models for the urban growth planning, environmental assessment, and decision-making needs the establishment of an appropriate level of confidence in their performance. The objective of this research is to explore the importance of using multiple assessment techniques in order to fairly evaluate the performance of land use models. An application is conducted by using the Land Change Modeler for Ecological Sustainability (LCM) which is an empirical and transition potential model. LCM is applied to model the agricultural to developed areas transition in Rennes metropolitan area (France). The land demand is estimated using the Markov Chain model; whereas, the transition potential map is implemented using the Multi-Layer Perceptron Neural Network (MLP) method based on historical changes and driving variables. The model performance is assessed based on a variety of the most commonly used validation techniques. At the study area level, the correctness and disagreement analysis shows that LCM performs better at predicting the amount than the allocation of developed areas. Additionally, landscape metrics reveal that LCM tends to predict a fragmented urban form, which seems evident because of the large number of the individual urban patches. At the municipality level, the error budget analysis shows that the model performance, which varies highly between different subareas, needs to be improved. Moreover, the cross-tabulation between the transition potential map and both the observed and the predicted agricultural to developed areas transitions reveals that the order of the transition potential values does not perfectly fit the observed change; whereas, the predicted change is not solely limited to areas with high potential.  相似文献   

13.
Approaches linking biodiversity assessment with landscape structure are necessary in the framework of sustainable rural development. The present paper describes a methodology to estimate plant diversity involving landscape structure as a proportional weight associated with different plant communities found in the landscape mosaic. The area occupied by a plant community, its patch number or its spatial distribution of patches are variables that could be expressed in gamma plant diversity of a territory. The methodology applies (1) remote sensing information, to identify land cover and land use types; (2) aspect, to discriminate composition of plant communities in each land cover type; (3) multi-scale field techniques, to asses plant diversity; (4) affinity analysis of plant community composition, to validate the stratified random sampling design and (5) the additive model that partitions gamma diversity into its alpha and beta components. The method was applied to three Spanish rural areas and was able to record 150-260 species per ha. Species richness, Shannon information index and Simpson concentration index were used to measure diversity in each area. The estimation using Shannon diversity index and the product of patch number and patch interspersion as weighting of plant community diversity was found to be the most appropriate method of measuring plant diversity at the landscape level.  相似文献   

14.
Today, competing land use is continuing to occur in many developed regions. In the Agricultural Development Zone of Western Sydney Region, which is characterised by complex landscape patterns, land use competition is widespread. From a land use planning perspective, identification of suitable locations for a given type of land use is necessary for decision makers to formulate land use alternatives in different locations, based on existing land potential and constraints. For such a region, use of a simple method that implements a categorical system and considers only inherent land characteristics in the analysis is often inadequate to arrive at an optimal spatial decision. The primary aim of this paper is to develop spatial modelling procedures for agricultural land suitability analysis using compromise programming (CoPr) and fuzzy set approach within a geographical information systems (GIS) environment. Five main sets of spatial data for use as decision criteria were developed by using fuzzy set methodology: a land suitability index (LSI) for maximising the land productivity objective; an erosion tolerance index (ETI) for minimising the erosion risk objective; a runoff curve number (CN) for maximising the water discharge regulation objective; an accessibility (RP) measure for maximising the land accessibility objective; and the proximity to water body (WP) for minimising the water pollution objective. An L p -metric was used in the analysis utilising different strategies with representative indices ranging from a situation where full tradeoff among criteria occurs to a noncompensatory condition. Different weighting combinations were also applied, and decision analysis was carried out by using values ranging from 0 to 1.0, where 1.0 is considered as an ideal point. The CoPr model demonstrated in this paper yielded a promising result, as several different techniques of sensitivity analysis show reasonably good results. Likewise, an overlay of that result with the present land use/land cover indicates a good corresponding spatial matching between existing land use (orchard and cultivated land), and the cells (land parcels) classified as the best in CoPr. The results are amenable to various map display techniques, either using continuous values or by defining different cut off points in the data space within a raster GIS environment.  相似文献   

15.
Human modification of land use and land cover change (LUCC) drives the change of landscape patterns and limits the availability of products and services for human and livestock. LUCC can undermine environmental health. Thus, this study aimed to develop an understanding of LUCC in the Yanqi Basin, Xinjiang, China, an arid area experiencing dramatic water and land resource use. A time series of satellite images (1964, 1973, 1989, 1999, and 2009) were used to calculate the index of landscape patterns to study the processes involved in changes to land uses and landscape patterns and the influence of this changes on landscape patterns. The results show that land uses in the Yanqi Basin have changed dramatically since 1964 with grassland being mainly converted to cropland. Landscape fragmentation and diversity have decreased in the study area, although landscape fragmentation increased from 1964 to 1999 and then decreased by 2009. The index of landscape diversity decreased from 1.64 in 1964 to 0.71 in 2009. The heterogeneity and complexity of the landscape increased during this period. In contrast, the index of dominance decreased from 0.85 in 1964 to 0.83 in 2009. Land use change drives landscape patterns of the development of the watershed toward diversity and a fragmented structure. Population growth, economic development, and industrial policies were the dominant driving forces behind LUCC in the Yanqi Basin. Sustainable use of land resources is a significant factor in maintaining economic development and environmental protection in this arid inland river basin.  相似文献   

16.
A Health Index/Risk Evaluation Tool (HIRET) has been developed for the integration of risk assessment and spatial planning using GIS capabilities. The method is meant to assist decision makers and site owners in the evaluation of potential human health risk with respect to land use. Human health risk defined as the potential adverse effects on human life or health is generally accepted as the most important aspect for site assessment and planning of remediation strategies. It concerns polluted sites that endanger human health on one hand and derelict land that does not cause the immediate risk on the other hand. In current state-of-the-art risk-assessment, long-term spatial and temporal changes of risks, in relation to changes in contamination patterns and land use functions, are not taken into account. The aim of this paper is to demonstrate the methodology developed for human health risk assessment in aspect of spatial and temporal domain. HIRET was developed as an extension for ESRI software ArcView 3.2 and allows performing dynamic human health risk assessment in long-term period, which is relevant for land use planning. The paper illustrates how such methodology can assist in environmental decision-making to enhance the efficiency of contaminated land management. A case study of contaminated site is given showing how data can be used within a GIS framework to produce maps indicating areas of potential human health risk.  相似文献   

17.
This paper developed an approach by the synthesis of remote sensing, landscape metrics, and statistical methods to examine the effects of landscape pattern, land surface temperature, and socioeconomic conditions on the spread of West Nile virus (WNV) caused by mosquitoes and animal hosts in Chicago, USA. Land use/land cover and land surface temperature images were derived from Terra’s Advanced Spaceborne Thermal Emission and Reflection Radiometer imagery. An analytical procedure using landscape metrics was developed, applying configuration analysis of landscape patterns in the study area. The positive reports of mosquitoes and animal hosts for WNV in fall, 2001–2006, were collected from the Cook County Public Health Department. Forty-nine municipalities were found to have WNV-positive records in mosquitoes and animal hosts in fall 2004. Socioeconomic data were obtained from the 2000 US Census. Statistical analysis was applied to WNV data in fall 2004 to identify the relationship between potential predictors and WNV spread. As a result, landscape factors, such as landscape aggregation index and the urban areas and areas of grass and water, showed strong correlations with the WNV-positive records. Socioeconomic conditions, such as the population over 65 years old, also showed a strong correlation with WNV-positive records. Thermal conditions of water showed a less but still considerable correlation to WNV-positive records. This research offers an opportunity to explore the effects of landscape pattern, land surface temperature, and socioeconomic conditions on the spread of WNV caused by mosquitoes and animal hosts. Results can contribute to public health and environmental management in the study area.  相似文献   

18.
Many recent developments in coastal science have gone against the demands of European Union legislation. Coastal dune systems which cover small areas of the earth can host a high level of biodiversity. However, human pressure on coastal zones around the world has increased dramatically in the last 50 years. In addition to direct habitat loss, the rapid extinction of many species that are unique to these systems can be attributed to landscape deterioration through the lack of appropriate management. In this paper, we propose to use of an ecosystem classification technique that integrates potential natural vegetation distribution as a reference framework for coastal dune EU Habitats (92/43) distribution analysis and assessment. As an example, the present study analyses the EU Habitats distribution within a hierarchical ecosystem classification of the coastal dune systems of central Italy. In total, 24 land elements belonging to 8 land units, 5 land facets, 2 land systems and 2 land regions were identified for the coastal dunes of central Italy, based on diagnostic land attributes. In central Italy, coastal dune environments including all the beach area, mobile dunes and all the fixed-dune land elements contain or could potentially hold at least one EU habitat of interest. Almost all dune slack transitions present the potentiality for the spontaneous development of EU woodlands of interest. The precise information concerning these ecosystems distribution and ecological relationships that this method produces, makes it very effective in Natura 2000 European network assessment. This hierarchical ecosystem classification method facilitates the identification of areas to be surveyed and eventually bound, under the implementation of EU Habitat directive (92/43) including areas with highly disturbed coastal dune ecosystems.  相似文献   

19.
Scale-dependent present-day landscape mapping and assessment were used to study the relationship among physical environment, land use, and degree of landscape modification in the Aral Sea region and the Karakum Desert, areas prone to desertification in the Commonwealth of Independent States (CIS). Applying geographic information system (GIS) techniques at global (1:15,000,000), regional (1:1,000,000), and local (1:300,000) scales, researchers found that large-scale landscape assessment and mapping allow them to recognize landscape changes under desertification processes and assess the type and intensity of these processes. Remote sensing has been widely used to evaluate data reliability, to fill information gaps, and to reveal the dynamics of land use types resulting from landscape changes.  相似文献   

20.
A distributed hydrologic modeling and GIS approach is applied for the assessment of land use impact in the Steinsel sub-basin, Alzette, Grand-Duchy of Luxembourg. The assessment focuses on the runoff contributions from different land use classes and the potential impact of land use changes on runoff generation. The results show that the direct runoff from urban areas is dominant for a flood event compared with runoff from other land use areas in this catchment, and tends to increase for small floods and for the dry season floods, whereas the interflow from forested, pasture and agricultural field areas contributes to the recession flow. Significant variations in flood volume, peak discharge, time to the peak, etc., are found from the model simulation based on the three hypothetical land use change scenarios.  相似文献   

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