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1.
国外沙漠化监测评价指标与分级标准   总被引:6,自引:0,他引:6  
利用国内外有关资料,从狭义沙漠化定义出发,介绍了联合国沙漠化监测评价指标体系、分级标准和评价方法。  相似文献   

2.
近年来宁夏对沙尘天气的监测及对沙漠化防治对策   总被引:1,自引:0,他引:1  
宁夏在全区范围内建立沙尘暴监测网络,开展对沙尘天气的应急监测。宁夏作为沙源区和沙尘过往的主要通道,2002年全区共监测沙尘天气12次,沙尘粒径多分布在大于2 1μm。为防治沙漠化,宁夏积极寻求国际间合作,采取退耕还林还草、划管封育、禁牧、把握人工降雨时机等一系列措施,加大对沙漠化的防治力度。  相似文献   

3.
阐述了小城镇开展生态监测的目的和意义,以及小城镇生态监测指标体系的建立原则,介绍了城市生态子系统环境监测指标体系、农村生态子系统环境监测指标体系和自然生态子系统环境监测指标体系的具体内容,以及相关的监测方法与技术。  相似文献   

4.
荒漠生态环境监测指标体系初探   总被引:1,自引:0,他引:1  
讨论了建立荒漠生态环境监测指标体系应遵循的五个原则,并提出初步的荒漠生态环境监测指标体系,将指标体系分为三个部分:(1)荒漠环境指标;(2)荒漠生物指标;(3)社会经济指标.  相似文献   

5.
生态环境动态监测与评价指标体系探讨   总被引:8,自引:0,他引:8  
分析了生态环境和生态环境质量的内涵,明确了生态环境监测与评价指标体系所涵盖的内容。认为生态环境的显著地域性特点决定了不同类型地区需建立相应的指标体系,并详细探讨了如何建立特定区域生态环境动态监测与质量评价指标体系。  相似文献   

6.
荒漠化监测指标体系初探   总被引:2,自引:0,他引:2  
随着荒漠化过程的不断加剧,荒漠化的监测已引起了全社会的广泛关注,然而由于缺乏一个科学可行的监测指标体系,以致荒漠化监测不规范,难以从整体上把握荒漠化的发展动态和趋势.本文论述了国内外荒漠化指标体系及其研究现状,指出了我国现有荒漠化监测指标存在的主要问题,提出了荒漠化监测指标的基本特征,建立荒漠化监测指标的基本思路并提出了一个量化监测指标体系。  相似文献   

7.
荒漠化及其监测   总被引:2,自引:0,他引:2  
本文通过对荒漠化过程的探讨,提出了荒漠化监测指标体系及监测评价方法,为新疆开展荒漠生态环境监测工作提供依据.  相似文献   

8.
选择甘肃省有代表性的草地生态环境———天祝县草地生态环境,进行生态环境监测指标体系敏感因子的筛选研究。通过实验、调查,收集大量数据资料,初步筛选、确定草地生态环境监测敏感因子,对所选敏感因子进行计算机处理与分析,确定敏感因子相关因素,从而建立数学模型;验证、修改和完善模型,最终建立草原生态环境监测系统简洁、高效的敏感因子指标体系,为建立和完善生态环境监测系统,准确、客观地评价生态环境奠定基础。  相似文献   

9.
通过对金昌市自然和沙漠化现状及成因的描述,提出了防治沙漠化几点建议。  相似文献   

10.
农村环境质量监测与评价指标体系研究   总被引:14,自引:0,他引:14       下载免费PDF全文
总结了农村环境质量监测与评价研究现状,提出了农村环境质量监测布点原则与方案,在此基础上构建了更具针对性、灵活性的农村环境质量监测与评价指标体系。  相似文献   

11.
The objective of this study is to develop techniques for assessing and analysing land desertification in Yulin of Northwest China, as a typical monitoring region through the use of remotely sensed data and geographic information systems (GIS). The methodology included the use of Landsat TM data from 1987, 1996 and 2006, supplemented by aerial photos in 1960, topographic maps, field work and use of other existing data. From this, land cover, the Normalised Difference Vegetation Index (NDVI), farmland, woodland and grassland maps at 1:100,000 were prepared for land desertification monitoring in the area. In the study, all data was entered into a GIS using ILWIS software to perform land desertification monitoring. The results indicate that land desertification in the area has been developing rapidly during the past 40 years. Although land desertification has to some extent been controlled in the area by planting grasses and trees, the issue of land desertification is still serious. The study also demonstrates an example of why the integration of remote sensing with GIS is critical for the monitoring of environmental changes in arid and semi-arid regions, e.g. in land desertification monitoring in the Yulin pilot area. However, land desertification monitoring using remote sensing and GIS still needs to be continued and also refined for the purpose of long-term monitoring and the management of fragile ecosystems in the area.  相似文献   

12.
在对荒漠化地区生态环境与社会经济评介基础分析的基础上,提出了荒漠化监测中生态环境与社会经济综合评价指标体系及评价标准,建立了初步的评价模型。并以宁夏自治区作为试点区域,对评价指标体系及其评价方法进行了验证。  相似文献   

13.
Modeling Desertification Change in Minqin County,China   总被引:1,自引:0,他引:1  
Monitoring environmental processes is becoming increasingly important wherever there is increasing population and economic development pressure placed on fragile environments. Remote sensing, digital image processing, and spatial analysis have proven to be useful technologies in both assessing and monitoring environmental change. In this study, they were used to assess desertification processes and change in Minqin County, China from 1988 to 1997. The results suggest that wind erosion was the dominant cause of desertification in more than half of the study area. Coupled with this were increases in salinization processes, affecting 33.62% of the land area in 1997. Overall, moderate desertification was found to be the dominant desertification grade (43.64% of total area), followed by extreme/severe desertification (26.15% of total area) in 1997. In addition, examination of landscape pattern changes indicated that desertification processes at the landscape level were becoming evident at increasing levels of fragmentation, complexity in shape, and isolation of patches. Major fluctuations in desertification type and grade were found at the fringes of oases, where an ongoing shift was taking place between cultivation, abandonment, and reclamation.  相似文献   

14.
To overcome the shortcoming of existing studies, this paper put forward a statistical vegetation–climate relationship model with integrated temporal and spatial characteristics. Based on this model, we quantitatively discriminated on the grid scale the relative role of climate change and human activities in the desertification dynamics from 1986 to 2000 in Yulin region. Yulin region’s desertification development occurred mainly in the southern hilly and gully area and its reverse in the northwest sand and marsh area. This spatial pattern was especially evident and has never changed thoroughly. From the first time section (1986–1990) to the second (1991–1995), the desertification was developing as a whole, and either in the desertification development district or in the reverse district human activities’ role was always occupying an overwhelmingly dominant position (they were 98.7% and 101.4%, respectively), the role of climate change was extremely slight. From the second time section (1991–1995) to the third (1996–2000), the desertification process was reaching a state of stability, in the desertification development district the role of climate change was nearly equivalent to that of human activities (they were 46.2% and 53.8% separately), and yet in the desertification reverse district, the role of human activities came up to 119.0%, the role of climate change amounted to ?19.0%. In addition, the relative role of climate change and human activities possessed great spatial heterogeneity. The above conclusion rather coincides with the qualitative analysis in many literatures, which indicates that this method has certain rationality and can be utilized as a reference for the monitoring and studying of desertification in other areas.  相似文献   

15.
荒漠化类型划分及其数量化评价体系   总被引:33,自引:0,他引:33  
从我国荒漠化监测的实际需要出发,提出了包括气候区、外营力、土地利用类型、地表特征和荒漠化程度在内的多因素复叠式荒漠化分类体系;既可适用于小区域大比例尺的重点监测,又可适用于大区域小比例尺的宏观监测的各荒漠化类型数量化程度判定指标体系和判定方法;适用于各级行政区的荒漠化水平评价方法.  相似文献   

16.
The desertification risk affects around 40% of the agricultural land in various regions of Romania. The purpose of this study is to analyse the risk of desertification in the south-west of Romania in the period 19842011 using the change vector analysis (CVA) technique and Landsat thematic mapper (TM) satellite images. CVA was applied to combinations of normalised difference vegetation index (NDVI)-albedo, NDVI-bare soil index (BI) and tasselled cap greenness (TCG)-tasselled cap brightness (TCB). The combination NDVI-albedo proved to be the best in assessing the desertification risk, with an overall accuracy of 87.67%, identifying a desertification risk on 25.16% of the studied period. The classification of the maps was performed for the following classes: desertification risk, re-growing and persistence. Four degrees of desertification risk and re-growing were used: low, medium, high and extreme. Using the combination NDVI-albedo, 0.53% of the analysed surface was assessed as having an extreme degree of desertification risk, 3.93% a high degree, 8.72% a medium degree and 11.98% a low degree. The driving forces behind the risk of desertification are both anthropogenic and climatic causes. The anthropogenic causes include the destruction of the irrigation system, deforestation, the destruction of the forest shelterbelts, the fragmentation of agricultural land and its inefficient management. Climatic causes refer to increase of temperatures, frequent and prolonged droughts and decline of the amount of precipitation.  相似文献   

17.
The improvement of land management practices on lands susceptible to desertification requires information on the status and condition of the existing resources as well as any change occurring in the resource condition over time. The Environmental Monitoring and Assessment Program (EMAP) of the U.S. Environmental Protection Agency has developed a statistical survey design for monitoring the condition of ecological resources on large spatial scales. EMAP-Rangelands used a uniformity sampling study in 1993 to evaluate response plot designs for three categories of indicators (soils, vegetation, and spectral reflectance) to be used for monitoring ecological condition of a site. The response plot design study was developed to integrate on-site measurements for the three indicator categories. The study was conducted on the Colorado Plateau in southern Utah in three rangeland resource classes (grassland, desertscrub, and conifer woodland) of differing productivity levels in an attempt to develop a common plot design for all three resource classes. Basic measurement units were developed to facilitate integration of data collection. Preliminary spatial analysis of the sampling study found considerable differences in variation patterns among the study sites and measurement categories for the indicator classes used by EMAP-Rangelands. Evidence of substantial trends in the indicator measurements on monitoring sites relative to regional trends leads to the conclusion that nonstationary spatial models for biological processes on a monitoring site may be needed to fulfill the requirements for developing plot designs and indicator criteria.The U.S. Environmental Protection Agency, through the Office of Research and Development, funded the research described here. This paper has been subjected to the Agency's peer and administrative review and has been approved as an EPA publication. The U.S. Government has the right to retain a nonexclusive, royalty-free license in and to any copyright covering this article.  相似文献   

18.
Monitoring of impacts of floods in river valleys of dryland regions has become important with the onset and threats of desertification and is likely to become even more vital with predictions of increased effects of climate and land use change. It is also needed in order to conform to requirements of the EU Water Framework Directive. Monitoring in such regions sets particular challenges. This paper explains a system of low-cost monitoring of changes in morphology, vegetation and sediment cover in channels and valley floors of ephemerally flowing streams. It has been applied in SE Spain for 10 years and has proved very effective. In particular, the use of simple crest-stage recorders for measuring flow height and the use of real-time differential GPS for rapid and accurate survey and for relocating points have proved very valuable. Part of the monitoring is focused on the interaction of plants and channel processes. Small changes in and around vegetation associated with flow events have been detected by a combination of quadrat surveys and cross-profiling of the channel. A range of flow events has been measured over the period of monitoring, demonstrating their differing effects and the varying sensitivity and responsiveness of different sites. The sporadic occurrence of flood events in such an environment means that a strategy of monitoring several sites and of continuation over many years has great benefits.  相似文献   

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