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1.
以县域为研究对象,从影响生态环境的自然因素、人类干扰因素两个方面出发,确定了包括目标层-准则层-指标层在内的系统化评价指标体系;打破传统的以行政区域为单元分析的模式,通过GIS网格技术和模糊综合评价多属性特征分析,提出了将地理信息系统技术(GIS)和AHP-模糊综合评价模型互相融合,以网格单元进行生态环境脆弱性综合评价...  相似文献   

2.
本文基于地理国情普查数据,结合水利、环境、统计、遥感影像等数据,以青海省乡镇(街道)为基本评价单元进行生态环境状况定量化评价,并在此基础上采用层次分析加权主成分分析(AHP-PCA)模型,以自然-经济-社会区域复合生态系统为框架,以县(市、区)为评价单元对青海省生态环境进行综合评价。评价结果显示青海省生态环境状况整体较好,各年评价结果为优、良的县(市、区)均超过一半,除个别地区外,全省各乡镇(街道)生境质量呈东部优于西部、南部优于北部的特征。  相似文献   

3.
在对某地区进行生态环境评价研究过程中,往往很难准确合理地确定各类评价指标的权重。层次分析(AHP)与模糊数学(fuzzy mathematics) 综合评判法是根据模糊数学的隶属度理论把定性评价转化为定量评价,建立模糊综合评价模型。确定地区的生态环境健康指标体系,分为目标层、准则层和指标层,并选取实验区的各类生态指标。采用组合赋权法确定各层次权重,然后计算出各指标的权重建立模糊综合评价模型,最后根据提取的遥感数据完成地区生态环境评价分级。运用基于AHP与模糊数学的综合评判法确定评价指标的权重,在GIS平台上对各评价指标进行加权叠加,得到地区生态环境的等级评价图,实现了地区生态环境评价。研究结果表明,使用该方法确定地区生态环境各指标权重所得的评价分级是与现实吻合的,这对于评价和保护地区生态环境具有现实意义。  相似文献   

4.
四川省若尔盖县生态环境质量评价   总被引:2,自引:0,他引:2  
本文以2007、2009和2012年的5月和9月共6个时期的遥感影像,基于栅格数据和综合评价模型,对若尔盖县的生态环境质量状况进行了评价。首先,从影响生态环境质量的因子出发,选取归一化植被指数(NDVI)、地表温度、坡度、坡向、土地利用、湿度指数6项生态因子作为评价指标;然后,利用主成分分析法确定各评价指标的权重,根据综合指数评价模型计算出研究区的生态环境质量指数,同时,依据计算结果的大小把研究区的生态环境质量划分为优、良、中、差4个等级;最后,对若尔盖县的生态环境状况的空间分布规律进行分析。结果表明,2007-2012年若尔盖县生态环境质量良好,不同时相的生态环境综合指数的均值均在60左右,同时该区域的生态环境质量有变好的趋势;不同季节的评价结果稍有差异,但是同一季节不同年的变化趋势是一致的;不同等级的区域相间分布,较差区域主要集中在植被覆盖较差的区域,西北部居多,中部零星分布。  相似文献   

5.
全球变化下北方农牧交错地带区域适应能力评价模型研究   总被引:4,自引:0,他引:4  
以可持续发展理论为指导,依据2006年全球变化人类行为计划(IHDP)第六届开放会议精神,参考前人有关生态环境评价框架和指标组合研究,建立了适合北方农牧交错地带特点的区域适应能力评价模型(PSRRAD),并对模型的构建思想、参数意义和评价指标的具体计算进行了探讨,以期为全球变化区域响应研究提供参考.针对北方农牧交错地带的实际情况,PSRRAD模型将第四纪地质地貌与现代生态环境研究整合,提出第四纪地质脆弱指数概念,在生态环境胁迫分析中,提出衡量农牧交错地带农牧业环境胁迫程度的地农牧业生产量指数的概念,使生态环境先天与后天胁迫因子、自然与人文因子得以客观体现,对生态环境脆弱性研究的时间和空间尺度均有所拓展.  相似文献   

6.
投影寻踪聚类(PPC)模型在多因素聚类分析中被广泛应用并取得了满意的效果,然而,模型还存在诸如密度窗宽参数取值经验确定等不足,有待改进提高.针对投影寻踪聚类模型存在的问题,首次把投影寻踪聚类的思想和动态聚类方法结合起来构造投影指标,建立了投影寻踪动态聚类(PPDC)新模型,新模型在整个运算过程中毋需人为给定参数,具有聚类结果客观、明确以及稳定性好、操作简便等特点.应用投影寻踪动态聚类模型对中国生态环境质量进行评价,获得了有切实意义的区划结果.此研究为生态环境质量评价开创了一条新途径,也进一步为生态保护、建设和监督管理提供科学依据和技术支持.  相似文献   

7.
在当前数据质量评估指标(多路径效应、数据完整率、周跳以及信噪比等)基础上增加数据有效率指标,首次提出利用多指标综合评价方法对全球iGMAS、MGEX、IGS等观测站的GPS数据进行数据质量分析,建立了TOPSIS综合评价模型,并将该模型综合评价结果与各指标进行Pearson相关分析,综合评价结果与数据完整率和数据有效率指标呈强相关;并采用静态PPP结果与该综合评价结果进行相关分析,亦呈显著相关。  相似文献   

8.
岷江上游汶川退耕还林(草)中“3S”技术的应用   总被引:3,自引:0,他引:3  
遥感(RS)、全球定位系统(GPS)和地理信息系统(GIS)技术的结合能快速、准确、动态及直观地查明研究区生态环境本底状况,建立生态环境本底调查数据库,为国家政府有关部门宏观管理决策与规划提供科学依据。本文以“岷江中上游生态环境遥感综合调查与评价”项目为例2,探讨利用“3S”技术在指导汶川地区制定退耕还林(草)政策和生态环境监测管理中的应用。  相似文献   

9.
秃尾河流域表生生态环境现状评价   总被引:1,自引:0,他引:1  
以地下水为主线,开展流域表生生态环境评价的方法研究尚处于发展之中。以秃尾河流域为例,紧紧围绕地下水这条主线,在建立流域表生生态环境递阶层次评价指标体系和评价标准的基础上,尝试采用模糊综合评判方法与模糊迭代自组织数据分析技术相结合,开展流域表生生态环境现状评价。评价结果表明,流域生态环境现状总体较好,其中盖沙丘陵区、河流源头和河谷阶地区及沙漠区是水资源与生态环境保护的重点,这些研究为评价生态环境脆弱区水资源开发利用对表生生态环境的影响以及保护流域水资源与生态环境提供了科学依据。评价结果与流域生态环境实际更为吻合,规律性更明显。  相似文献   

10.
本文应用地理信息系统所具有的巨大数据综合处理、空间分析和模型运算等技术优势 ,评价与分析福建农业生态环境中的土壤侵蚀、土壤污染、土壤养分贫瘠和功能稳定性等重要问题 ,提出区域特征的空间分布.  相似文献   

11.
《山地科学学报》2020,17(8):1916-1930
In recent years,the ecological environment along highways in Tibetan Plateau has been severely affected due to the rapid construction of highways.In order to solve the problems of multiple indicators and inconsistent criteria in the ecological impact assessment of highways,and to scientifically screen assessment indicators,the paper proposes a multi-round indicator screening method,which combines literature analysis,expert rating,and statistical analysis.Based on this screening method,normalized difference vegetation index,land surface temperature,elevation,and normalized difference soil index are screened out.Combined with multiple linear regression,an ecological impact assessment model is established and applied to ecological impact assessment of Gonghe-Yushu Expressway.The results show that the expressway construction is the first driving force for the deterioration of the ecological environment along the roadside,and its interference range on the desert grassland ecosystem is greater than that on the agroforestry system.The ecological environment within 150 m on both sides of the expressway should be protected.  相似文献   

12.
Desertification, soil salinization and grassland degradation are the major environmental hazards faced by the Gannan Plateau, northeastern Tibetan Plateau. Ecological risk assessment plays an important role in formulating environmental management strategies yet little attention to this region. In this study, we established an ecological risk assessment index system based on 30 evaluation indices in the categories of hydrometeorology, ecological environment, ground surface disturbance, and society and economy for the Gannan Plateau. An entropy method was used to calculate an index weight, and subsequently the matter-element method was used together with extension theory to establish a matter-element extension model of ecological risk. We assessed the ecological risk in this region by calculating the degree of association between index layer, system layer and target layer, and the cumulative ecological risk index. The degrees of ecological risk for the counties of the region were determined by using ArcGIS which would represent a spatial heterogeneity of the risk grade in production. Our results showed that the areas of high ecological risk were in Zhouqu County and Zhuoni County, and others were of low risk (Hezuo City, Diebu County, Xiahe County and Lintan County) or intermediate risk (Maqu County). The results of the assessment were in accord with the actual observed situation. Thus, our ecological risk assessment index system is appropriate for this region and suggests that high risk counties need a priori ecological protection. Such research could provide a technological support which would potentially prevent or reduce disasters by establishing an ecological barrier to promote the sustainable development of Gannan Plateau.  相似文献   

13.
从评价工作等级、评价范围等方面明确公路建设生态环评编制中易忽略的几个问题,籍为提高环评大纲及报告书编制质量有所裨益。  相似文献   

14.
城市生态环境地球化学风险性评价已经成为地球化学界普遍关注的问题,近年来我国进行了大量的城市地球化学工作,但还没有形成一个公认的、完善的系统评价体系与方法。结合济南市发展现状,尝试从城市化进程和城市地质环境角度,提出城市地球化学系统评价体系的模型,以期协调城市化进程中人为扰动(工程活动等)和地质环境的对策,也是对城市环境地球化学工作的一种探索。  相似文献   

15.
Habitat richness influences and even determines biological diversity. Plant habitat suitability assessment can provide technical guidance and information support for ecological restoration. Thirteen factors in three categories of terrain, meteorology and soil were chosen to build a habitat suitability assessment index framework in the Upper Reaches of the Min River, based on the local natural environment and the actual influencing factors of vegetative growth. Combined with the Analytic Hierarchy Process(AHP) and entropy method, which were used to calculate weights of indexes, habitat suitability was studied by using a multi-objective linear weighting model and geographic information systems(GIS) spatial analysis techniques. The assessment results are as follows: Altitude, soil stability, aspect and slope have more important effects on plant habitat suitability in the Upper Reaches of the Min River, and their weights are 0.311, 0.260, 0.198 and 0.125, respectively. Suitable and sub-suitable habitats cover 4431.80 km2 and 6171.12 km2, respectively; most of which are distributed along both sides of rivers and have higher suitability. Unsuitable habitats cover the largest area(6679.76 km2), accounting for 29.83% of the whole area; and the worst unsuitable habitats are 5107.23 km2(22.81%); they account for more than half of the studyarea. These results indicate that the plant habitat in the Upper Reaches of the Min River is poor and ecological restoration is both urgent and difficult. Therefore, based on the principle of taking measures suitable to the habitat in ecological restoration projects, ecological and engineering measures should be combined to have better effects, while increasing the strength of ecological protection.  相似文献   

16.
本文以南水北调中线工程核心水源区淅川县为例,选取2004年TM、2014年GF1号影像等数据,解译获取了淅川县土地利用数据,对2004-2014年淅川县土地利用变化进行定量分析。通过选用区域生态环境质量模型,对研究期内淅川县土地利用变化的生态环境效应进行评估,并采用灰色关联法对导致淅川县生态环境质量变化的驱动因素进行分析。研究结果表明:① 2004-2014年,林地、建设用地和水域面积增加,耕地面积减少。在林地资源演化趋势上,有林地、疏林地、灌木林地和苗圃地与林地资源的整体演化格局一致,而宜林地和无立木林地、未成林造林地呈减少的趋势;② 在空间分布上,林地主要分布在海拔高、坡度较陡的北部山区,耕地和建设用地密集分布于海拔低、相对平缓的东南部地区;③ 2004年和2014年2期生态环境质量均在县域内表现出明显的空间差异,呈现出北高南低的分布趋势。研究期内淅川县区域生态环境质量指数从0.5443上升至0.6039,生态环境质量提高,其中宜林地和无立木林地转化为有林地、退耕还林对区域生态环境改善贡献最大;④ 局部地区生态环境呈负向发展,其中对森林资源采取掠夺式开采和粗放型管理、毁林开地对县域生态环境产生的负面影响最为深刻。⑤ 2004-2014年县域生态环境质量变化主要由政策和居民追求利益最大化的行为所驱动。  相似文献   

17.
In order to clarify regional ecological security status and formation mechanism of regional ecological security barriers in underdeveloped regions of China, we took Yunnan province as a case to evaluate its regional ecological security by using entropy matter-element model, comprehensive index and GIS spatial method, and we diagnosed its obstacle factors through obstacle degree model. We found a low overall level of regional ecological security in Yunnan. Only Kunming fell into the good level, 68% of the regions were below the critical safe level. For the vast majority of regions in Yunnan, their regional ecological security was unstable. The indexes related to per capita resources, geological and topography environment, economic, and technology were at the unsafe or dangerous level. The indexes related to urban expansion, level of income, cultivated land quality were at the level of critical safety. The indexes concerning urban management capacity, air quality and water environment were at the good or ideal level. Yunnan’s regional ecological security was not good due to natural obstructive environment itself, simultaneously lower backward economic and social level restricted the ability of ecological security response to manage ragile ecological environment. The results of the composite index were roughly consistent with those of the entropy weight matter-element model. The mean values of the classification index, from high to low, were: the state index > the response index > the pressure index. The state index and the response index had a significant mutual promotion to each other. The regions with good composite index, state index and response index mainly distributed in the central regions of Yunnan Province. Spatial autocorrelation of regional ecological security level in Yunnan was not obvious. Water resources, economic and social development were main obstacle factors of the regional ecological security. When distinguishing with obstacle type, Kunming belonged to natural ecological environment barrier type, while other regions belonged to economic and social barrier type.  相似文献   

18.
通过遥感解译、水土样测试、环境地质调查,从地表水、坑塘水、平原水库、浅层地下水、土壤环境的质量评价入手,查明了东营市湿地的分布现状,分析湿地演变与地质环境条件之间的相关性,构建东营湿地地质环境脆弱性评价体系并进行了脆弱性评价,为促进湿地生态系统与区域地质环境协调发展提供科学依据。  相似文献   

19.
随着国家对生态环境的重视和水土保持科学的发展,有关土壤侵蚀危险性评价的研究越来越重要。本文对土壤侵蚀危险度评价的一般方法进行了改进。首先,分析了安溪县各强度等级的土壤侵蚀在高程、坡度、土地利用类型和土壤类型的面积分布情况,计算了不同高程带、不同坡度、不同土地利用类型和土壤类型的土壤侵蚀综合指数然后,以各影响因子的土壤侵蚀综合指数为权重,计算了不同侵蚀影响因子在安溪县各子流域的土壤侵蚀危险度,既避免了权重确定的主观性,又保证了土壤侵蚀危险度的计算适合当地的实际情况,从而明确了各子流域土壤侵蚀发生的可能程度最后,依据土壤侵蚀危险度和土壤侵蚀强度的分布规律,对整个研究区进行了水土保持分区,提出了治理方向。  相似文献   

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