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陕北风沙过渡区土地利用变化及其生态效应分析

Analysis the Effect of Land Use/Cover Change on Agro-Pasture Zigzag Zone

【作者】 王晓峰

【导师】 任志远;

【作者基本信息】 陕西师范大学 , 自然地理学, 2004, 硕士

【摘要】 区域生态安全是国家安全和社会经济安全的基础。从根本上讲,区域生态安全是国家和区域可持续发展的基础,没有良好的生态环境就没有区域乃至国家的可持续发展。 土地利用/覆盖变化不仅客观地记录了地球表面的空间格局,而且还再现了地球表面景观的时空动态变化过程。土地利用变化可引起许多自然现象和生态过程的变化,如土壤养分和水分的变化,地表径流与侵蚀,生物多样性的分布和生物地球化学循环等,这说明土地利用/覆盖变化与生态环境安全密切相关。所以从土地利用变化入手,研究其对生态环境的影响,是一个有效地方法,对于了解和调控区域生态环境乃至全球环境变化都具有重要的意义。 通过对土地生态系统服务的定量研究,可以为土地生态资源的合理定价与生态经济管理和有效补偿提供科学依据。同时,可以明确体现区域各生态系统的重要性,确定优先保护的生态系统和保护地区。在此基础上,才能科学的进行生态区划和生态规划,在时间尺度和空间尺度上实现资源的合理利用,保证了区域内与区域间、当代人以及代际间资源利用的公平性,最终实现区域可持续发展。 本论文选择了我国生态状况堪忧的陕北长城沿线风沙过渡区。它不仅是国家煤炭开发重点能源化工基地,又是国家防治土地沙化和治理水土流失的重点区域,即本区存在着能源开发(这不可避免的会带来一系列环境问题)和进行生态建设这样一对矛盾,对区域生态安全有着十分重要的意义。 本论文分析了土地利用变化的研究进展,论述了研究区生态环境背景及其特征,分析了其历史时期土地利用特点、土地利用现状,重点分析了土地利用的动态变化特征,以及土地利用所引起的生态环境响应,确定土地生态系统的服务功能,建立了陕北长城沿线风沙过渡区生态系统服务功能单位价值测评体系,计算了其生态系统服务价值;建立了土地利用变化驱动力模型,在定量的基础上,从政策、人口、经济和自然等因素分析了土地利用变化的驱动力。研究结果表明: 1.本区在近10年中,耕地、水域和未利用土地面积在持续减少;而其它各类土地面积都成不同程度的增加,其中园地面积的变化幅度最大,居民工矿地和交通用地一直呈增长趋势。 2.陕北风沙过渡区近年来土地利用变化强烈,年平均变化率为0.4%;在县域空间分布上,土地利用变化速率差异明显。各土地利用类型的相对变化程度不等,变化最大的是园地、交通用地等;变化最小的有牧草地和水域。 3.通过土地利用转化矩阵表的分析,在农业用地内部,各类土地的转化比较剧烈,主要是耕地转为圆地、林地和牧草地,同时,林地和牧草地也有一部分被开垦为耕地。农业用地和建设用地之间的转换也比较明显,总体是大量的耕地被建设占用。未利用土地转向农业用地、建设用地的趋势明显。但不容忽视的是,沙漠化的现象仍然存在,并且在区部地区还有恶化的趋势。 4.由于本区是我国水土流失最为严重的区域,也是沙漠化潜在的区域,属于我国水土保持和沙漠化防治的重点地区,所以本区生态系统服务功能主要为防治土地沙化、水土流失和土地退化,即保岸固沙、固岸拦泥和固土护坡等功能。 通过计算得出生态系统服务价值表,2002年本区生态系统服务价值为152.56Xl了元,比1988年增长6.22X10s元,可见近年来生态生产力在逐渐上升,生态系统服务功能在优化。但耕地、水域和未利用土地的生态价值呈减少趋势,其中耕地服务价值减少最多;其它土地类型的服务价值都呈不同程度的增加,林地和园地的服务价值增长最大。从各服务功能的价值量看2002年废物处理的价值量最大,77.09 X10,元,占总价值的46.39%,其次是水分供应和食物生产,其价值量分别是31 Xl护元和n.99X10,元。价值量最小的是水分控制和基因资源,它们分别仅有0.12 X 10a元和0.13 x 105元。 5.土地利用变化是在受到各种因素的综合作用下发生。在近年主要为政策因素、人口因素、经济因素和自然因素。政策因素主要是:西部大开发背景下的退耕还林还草,封山育林以及我国小城镇发展方针的影响;人口因素中,非农人口的增加对耕地的影响显著;经济因素中主要是农业比较利益的低下;在自然因素中,风,水和气温对土地利用变化的影响明显。 本论文的独特之处是选择研究陕北长城沿线风沙过渡区(它不仅是国家煤炭开发为重点的能源化工基地,又是国家防治土地沙化和治理水土流失的重点区域,也是农牧交错带这样一个多重过渡区),这种多重过渡区是土地利用变化研究的热点地区,因而论题本身就具有较强的现实意义。此外,本文在调查考察资料的基础上,大量应用遥感数据进行土地利用现状分析。同时本文的另一个特点是应用地理信息系统软件arcview, arcinfo的强大空间分析功能,进行土地利用变化的空间分析,并建立了土地利用变化数据库。最后在表达方式上,充分应用Gls的自动制图功能,以直观的形式,直观的表现土地里用变化的空间差异。本文对土地利用研究的基础上,探讨了土地生态系统服务功能,定量的计算了风沙过渡区生态系统服务价值,为生态效应的动态变化定量分析提供了方法和依据。

【Abstract】 The regionally ecological security, the foundation of the national and social economic security, fundamentally, is the basis of the national and local sustainable development. No good ecological environment, no sustainable development of the region and even the country.LUCC not merely records objectively the space pattern of the earth surface changed by humans, but represents the varied course of dynamic space-time of the landscape of the earth surface. LUCC can result in a lot of natural phenomena and the transform of ecological course, for instance, the change of soil nutrient and moisture, rainwash and corroding, distribution of bio-diversity and living beings’ geo-chemical circulation, etc, which proves that LUCC is closely related to the ecological environment security. As a result, through researching the influence LUCC made on the ecological environment, we are able to understand and adjust the change of the regionally ecological environment and even the global environment.The quantitative research to the land’s eco-systematical service can offer the scientific basis for the reasonable pricing of the land’s ecological resource and the management and effective compensation of the ecological economy, which can also embody the importance of the diverse ecological system in the region, which can help humans determine the ecological system and area that should be protected priorly, only on this basis, we can design and plan the ecology scientifically, utilize the resource reasonably both in time and space, ensure the fairness of the using resource in the region and between regions for the contemporary generation and next generations, and finally realize the regionally sustainable development.The thesis chooses the transitional region of the wind and sand along the Great Wall in the northern Shaanxi Province, the ecological condition of which is severe. Theplace is the base of chemical energy--the country’s important coal site, as well thekey area where the sand of the land and the soil erosion are being prevented and converted. In a word, there is a contradiction between energy development andecological construction and it is very vital how to solve the contradiction.The thesis illustrates the research development of LUCC, describes the background of the ecological environment and its characteristic in the region, analyses the features and present situation of LUCC, mainly its dynamic features and the response to the ecological environment caused by LUCC, ascertains the serving function of the land’s ecological system, calculates the value of service of ecological system in the region, sets up the driving model of LUCC, on the basis of ration, analyses qualitatively the driving of LUCC in the aspect of policy, population, economy, nature and so on. The results show that:1.In the past decade, plantation, water area and unutilized area are decreasing, whereas other kinds of area are increasing in some different degree.2.The land use/cover changed greatly in the region along the Great Wall in northern Shaanxi province during 1988-2002.The cultivated land ,unused land and water region are all shrinked ,but the unused land changed most greatly ;the others all increased ,especially the orchard increased greatly.3. According the matrix of land use change, cropland land change was the most imported type ,which was mainly transformed to orchard .forest .grassland ,dwelling land and others ,among which forest ,grassland and dwelling land have more proportion ;unused land mainly transformed to forest ,grassland ,trafficked land etc.4.LUCC is a complex system , which is affected by many comprehensive factors ,including both socio-economic and natural and environment .In Shenmu county ,the policy was the fundamental driving force of LUCC ;in addition ,human activity is a directly factor that drove the LUCC ;Besides the economical factor also affect LUCC in some extent.

  • 【分类号】F301.2
  • 【被引频次】2
  • 【下载频次】589
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