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1.
区域土地资源优化配置及其可持续利用   总被引:30,自引:0,他引:30  
从土地利用优化配置入手,介绍了其基本内涵和研究进展,阐述了土地资源可持续利用的途径与目标以及评价方法,建立了区域土地利用持续评价模式。  相似文献   

2.
广西都安瑶族自治县农业可持续发展的生态安全评价   总被引:19,自引:0,他引:19  
以广西都安瑶族自治县为例,建立都安农业可持续发展生态安全评价指标体系,对都安农业可持续发展进行生态安全评价,进而作出生态安全区划,并提出了不同生态安全区的土地利用与生态安全建设对策。  相似文献   

3.
农业土地利用变化及原因、效应分析   总被引:3,自引:0,他引:3  
利用航空遥感影像结合野外调查方法,获取了研究区域1979年和1999年土地利用类型图,并分析了该时段土地利用变化情况。通过农户调查,探讨了土地利用变化的原因。分析表明,技术水平提高和投入增加是耕地产量提高的重要因素,提高土地经济收益是旱地土地利用结构变化的直接动力。  相似文献   

4.
通过对农业土地利用系统的过程和输入-输出特征解析,构建了农业土地利用系统概念模型,从系统输入、土地利用过程和输出3个方面分析了农业土地利用过程中的环境风险源,探讨了针对农业土地利用系统的环境风险识别与评价方法。在此基础上,以乡镇为评价单元,逐一识别相应的环境风险因子,评价各类环境风险水平,并依据每个评价单元需要关注的风险种数评价其综合风险水平。以湖南省桃江县为例,对该县农业土地利用系统中的污水灌溉、肥源投入、农药投入、地膜施用和秸秆焚烧等人为因素带来的环境风险进行评价,结果表明,由于该县南部地区的工厂和采矿活动密集以及土地利用集约度高,农业土地利用系统的综合环境风险程度呈南高北低的趋势。  相似文献   

5.
以广西都安瑶族自治县为例 ,建立都安农业可持续发展生态安全评价指标体系 ,对都安农业可持续发展进行生态安全评价 ,进而作出生态安全区划 ,并提出了不同生态安全区的土地利用与生态安全建设对策。  相似文献   

6.
以北方农牧交错带典型生态示范村尧勒甸子村为例,应用参与式农村评估法(PRA)并结合GPS与野外测量,恢复了该村1949年后50a来的土地利用历史过程与格局,利用GIS分析其1950-1999年的土地利用变化特点。运用因子分析和逐步回归分析方法揭示了人类活动因素对土地利用变化的作用。结果发现:1985年以前耕地面积扩大,草地面积减小,沙地面积迅猛持续增加;1985年以后土地利用变化向相反的方向发展,土地利用结构趋向合理。  相似文献   

7.
广西土地利用变化及对粮食生产的影响   总被引:4,自引:0,他引:4  
在统计软件SPSS支持下,深入分析了广西土地利用现状及1996—2001年土地利用结构变化的原因,在此基础上探讨了土地利用变化对粮食生产的影响,并提出了一些保障粮食安全的对策及建议。  相似文献   

8.
土地利用/覆被变化在全球变化中占有重要地位,对于综合模拟和评价环境问题非常重要。区域案例研究方法是土地利用/土地覆被的研究核心,以中尺度的三江平原北部作为研究区域,重建并分析了自1954年以来该地区4个时段的土地利用/土地覆被格局及其时空演化过程,在此基础上重点分析了20世纪50年代以来耕地的开发过程。结果表明1954年到2000年期间,以湿地、草地和林地转换成耕地为该区域土地利用/土地覆被变化的主要形式,耕地面积由占总面积的5.29%上升到51.81%,同时湿地占总面积的52.49%下降到15.71%,并指出人类的农垦活动是湿地减少和生态环境恶化的根本原因。  相似文献   

9.
南京市土壤重金属污染调查评价   总被引:28,自引:0,他引:28  
在南京地区总共采集土样36个,以《土壤环境质量标准》GB15168-1995二级标准为评价标准,对南京市土壤重金属Pb、Zn、Cr、HB、Cu的污染状况作了初步评价。研究发现南京近郊重金属污染以汞和锌为主,江宁县附近为污染重区。污染原因有:工矿企业废物的排放;各类肥料和农药的施用;生活垃圾的农用。在评价的3种主要土地利用类型中污染比较严重的是受人为影响比较大的菜地和水田,说明人为影响是土壤重金属污染的主要原因。  相似文献   

10.
根据现状基础数据,以及城市发展对土地利用的需要,对建三江城区绿地和土地利用状进行了分析与评价。通过对现有林地、水系生态要素的有机组织和改造,确定了建三江城区绿地生态系统用地规划目标和绿地生态系统布局,"一廊、两环、三楔、多点、网络",为北方寒地城市建三江城区的生态宜居城市建设提出了建议。  相似文献   

11.
SUMMARY

Over-population in relation to poor land productivity and cultivation in less fertile lands is resulting in land degradation and deforestation in UP hills. Growing demand of more food production and increasing need for more cash in hand have forced the hill people to cultivate all kinds of land, resulting in the denudation of land resources and soil erosion. These changes resulted in out migration of the area's human resource. A new management system for the revival of natural resources and the sustainable utilization of the area's human population and livestock has been proposed, involving active local participation in order to change the existing land-use to a system based on the soil fertility scale.  相似文献   

12.
The North China Plain is one of the most important production areas for wheat and maize in China, and also has the densest agricultural population in China. How to use and develop the limited land resources reasonably, and improve and protect them, have become issues of major concern. This paper is based on sustainability theory, reviewing the fundamental principles of sustainability, and developing an index system with which to evaluate the sustainability status of land use. We also use this method to evaluate the land-use status of the North China Plain and to analyze current factors affecting sustainable land use in this area. In addition, we propose a specific method for evaluating sustainable land use.  相似文献   

13.
SUMMARY

The Lesser Himalaya, as the most densely populated part of the tectonically active and ecologically sensitive Himalayan mountain ranges, deserves specific attention to the conservation of the environment and the sustainable development of natural resources. Rapid growth of the human population during recent years, and the absence of any viable means of livelihood other than uneconomic crop farming have led to the uncontrolled exploitation of land areas and the consequent degradation and depletion of critical biophysical resources in the region. The need for sustainable development in Himalaya, therefore, makes it imperative to adopt a comprehensive land-use policy based on land capacity analysis that is scientific and practical. The main objective of this paper is to evolve an optimal land-use framework for the Gomti Watershed, situated in Kumaon, Lesser Himalaya. A detailed study of the traditional land use, regional agricultural system and the areas prone to environmental hazards was made throughout the watershed, through the preparation of large scale topographical forest and land record maps, field surveys and mapping. The average slope was considered as the principal parameter of land capacity, the potential for landslides and the intensity of erosion. Recognising the drastic changes that have taken place in the traditional land use, the watershed area has been proposed to be defined as protected forests (33.41%), community forests (32.86%), cultivation (23.33%) and horticulture (8.30%).  相似文献   

14.
人为作用对土壤环境质量的影响及对策   总被引:2,自引:0,他引:2  
人为作用引起的土壤环境变化是衡量和反映土壤资源与环境质量的标志,它与当前世界关注的全球变化和可持续发展密切相关。本文着重讨论近百年来土壤环境的变化以及未来土壤环境变化的新趋势。通过大量的数据,阐述由于人为作用,上地退化和水土污染问题日益严重。文章还进一步从气候变化、人口压力和大型工程建设等几方面对未来土壤环境的影响进行了预测。最后提出了防治土地退化、水土污染及提高土壤环境质量的对策。  相似文献   

15.
土地资源是人类赖以生存的最基本的自然资源,土地资源的永续利用是实现社会、经济和生态全面可持续发展的基础。本文在分析土地资源利用特点,土地资源永续利用的内涵、原则与指南的基础上,提出了实现土地资源永续利用的一系列生态经济对策。  相似文献   

16.
SUMMARY

The notion of sustainable development in the context of water resources is discussed. Facing the increasing pressures — population growth with consequences for settlements and production of food and fibre, and human aspirations to better living standards — the business-as-usual approach to water development and management cannot he globally sustainable. The need for curbing water demands and for ‘doing more with less’ are gaining growing recognition in our increasingly thirsty planet. An integrated approach to freshwater resources is needed, based on the perception of water as a natural resource, part of the ecosystem, and an economic and social good. It is discussed how hydrological extremes jeopardize sustainable development. Sustainability-related properties of drought and flood preparedness and mitigation measures are reviewed. Even if the term ‘sustainable development’ has been typically used in a qualitative sense, in order to compare how different options (e.g. flood protection alternatives) fare with regard to sustainable development, one needs at least rough quantitative measures. A sample of relevant indices is reviewed. It is advocated that hydrological observations should be recognized as an essential component of sustainable development and management of water resources.  相似文献   

17.
甘肃省耕地资源转变为建设用地的价值损失评估   总被引:6,自引:0,他引:6  
依据耕地资源具有的社会保障功能、生态系统服务功能和经济产出功能,初步建立耕地资源的价值评估体系,综合运用市场价值法、替代法、机会成本法和影子价格法等评价方法,估算了甘肃省12个市(州)2007年耕地转变为建设用地所导致的正面效应价值损失。结果表明,由于建设用地占用耕地造成的价值损失相当巨大,2007年全省建设所占用耕地的总面积为1 564.66 hm2,造成的价值损失多达95 904.09万元,各市(州)1 hm2土地的损失都超过了45万元。从价值损失的构成来看,损失的直接使用价值为45 712.77万元,间接使用价值达50 191.32万元。可以看出,耕地资源除为社会提供直接产品价值外,还有巨大的间接使用价值,而且这种价值对人类的贡献比农产品的产出价值更为显著。  相似文献   

18.
随着全球人口不断增加和经济持续增长,自然环境和资源受到的压力将越来越大.人们面临很多挑战.而这些挑战又与资源、环境、人口、贫困、体制等问题密切相关,它们是涉及当前可持续发展的一系列重大问题.因此,我们必须以这些问题为切入点探讨实现可持续发展的对策.分析济南市生态环境现状和资源利用现状,并找出存在的问题.在此基础上提出济南市生态环境和资源可持续利用的对策措施,对城市的发展提供依据.图2,参7.  相似文献   

19.
The EU vision of sustainable agriculture, land use, forestry and management of natural resources contributes to the balanced exploitation of the environment, taking into account rural development strategy. Whilst the EU directs activities through legislative tools, national systems of public administration are responsible for the implementation of the respective laws. Despite there not being acquis communautaire in public administration, non-formal cooperation has nevertheless emerged and systems of national public administration have to meet EU criteria and ensure the effective implementation of legislation. The paper presents an analysis of how Slovak state administration has converged with EU requirements in the field of sustainable agriculture, land use, forestry and natural resources. Administrative convergence is considered through the internal convergence represented by capacities without legal subjectivity, and through external convergence represented by legal and administrative subjectivity. Both approaches are observed at the central level within specialized public authorities. Local state administration is characterized by the creation of internal administrative capacities with the challenging delimitation of which competences are affected by the process of administrative convergence.  相似文献   

20.
In recent years, China's cultivated land has been shrinking, a change which has become one of the potential challenges to national sustainable development and global food security. In our research, we have predicted China's cultivated land resources for the next 50 years, based on scrutiny of systematic data and analyses of the loss of cultivated land. We have also designed an indicator of cultivated land equivalent per capita (CLEPC) to assess the capacity of cultivated land to support our population. The results show that China's cultivated land will decline to a minimum of 113.31 million ha between 2001–2010, while cultivated land per capita will decline from 0.101 ha to 0.083 ha. After 2010, the area of cultivated land will begin to increase slowly to 118.98 million ha in 2050. However, cultivated land per capita will still decline to 0.079 ha between 2010–2030; after 2030, it will start to increase and reach 0.085 ha in 2050. In contrast to the total area and per capita area of cultivated land, the CLEPC will remain at 0.101 ha between 2001–2010, and then increase to 0.156 ha in 2050. Overall, there will be increasing stress on China's cultivated land during the next two or three decades. Although the supporting capacity of cultivated land may not decline obviously with improvement in agricultural technology and infrastructure, China has to make great efforts to reduce the loss of cultivated land and to improve its productivity to ensure food security in the near future.  相似文献   

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