【作者】 谢霞；

【作者基本信息】 新疆大学 ， 生态学， 2010， 博士

【摘要】 目前,可持续发展已逐渐成为人类实现社会、经济、资源与环境发展的最高目标,然而人口的急剧增加以及对资源的不合理利用,使得生态系统自身的协调能力不断下降,人类生存的环境也呈现出越来越脆弱的趋势,严重阻碍着可持续发展的进程。生态脆弱性研究通过对区域生态环境的现状及其在外部环境变化的胁迫下可能发生的变化趋势进行分析,可基本掌握脆弱生态环境区域的形成与演化机理。艾比湖区域生态系统严重退化、生态环境十分脆弱,正确认识和评价其生态环境脆弱性本质,监测生态环境演变的规律并加以恢复和重建,在西部大开发的前题下,对实现艾比湖区域环境和经济的可持续发展具有重大现实意义。本文选取艾比湖区域为典型研究区,以现代生态学、地理学、土壤侵蚀原理、土地资源学的理论和方法为指导,运用空间信息技术,以1990、2001和2007年3期Landsat TM/ETM+遥感影像为基本数据源,分析该区域的景观格局并获取景观指数,提取研究区土壤侵蚀、土壤盐渍化信息,同时建立土壤侵蚀和土壤盐渍化敏感性指数模型,以此为基础建立艾比湖区域综合生态环境脆弱度评价模型,并获得全区生态环境综合脆弱度分布图,研究艾比湖区域生态脆弱性及其动态变化过程。最后,对研究区的生态脆弱性提出分区恢复与保护的对策。研究取得了以下主要结论：利用SVM分类法,将研究区划分为耕地、林地、草地、水域、城乡建设用地和未利用地6种景观类型。通过动态度模型、景观转移矩阵、重心模型以及景观指数对研究区景观格局进行分析。研究表明,艾比湖区域景观格局发生了较大的变化。从整个研究时段来看,在耕地、城乡建设用地面积急剧增加以及林地面积小幅度增加的同时,草地、水域等景观类型均都有不同程度的减少,而土地沙漠化、土壤盐渍化的问题也依然不容忽视。耕地、林地、未利用地与草地之间的转化比较明显,水域和未利用地之间的转化较为显著。景观的重心有整体向东迁移的趋势,这和人工绿洲扩大是密切相关的,同时指征绿洲重心的迁移方向。在转入贡献率中最占优势的是耕地,转出贡献率最占优势的是未利用地,进一步说明随着当地经济近十几年的快速发展,人们不断调整农业经济结构,开垦了大量的荒地。城乡建设用地的分离度最大,说明该种景观类型分布较为复杂,其破碎化程度也较高。根据PPU指数对景观破碎度进行分析可以发现,研究区近20年总的变化趋势是景观的破碎化程度在降低,聚集度在逐渐增强,景观内优势斑块的连接性也在增强。城乡建设用地的SqP指数值增加的同时其余景观类型的SqP指数值均减少,说明绿洲主体部分的斑块复杂度在降低。选取分离度指数、PPU指数和SqP指数共3个景观格局指数,同时选用了土壤侵蚀敏感性指数和土壤盐渍化敏感性指数来完善研究区生态环境脆弱性的景观生态学评价。以建立的景观类型生态脆弱度指数模型为基础,利用景观类型脆弱度指数与各景观类型面积的比重构建了区域综合生态脆弱度模型XEVI,能够从空间上反映整个区域的生态环境脆弱性特征。评价结果表明,研究区以一般脆弱区为主,主要分布在艾比湖西侧的博乐市、达勒特镇、贝林哈日莫墩乡、精河县等组成的绿洲内部。无脆弱区和轻微脆弱区主要分布于艾比湖湖区、整个研究区的外围以及绿洲内部的部分区域。中等脆弱区主要位于绿洲内部的未利用地和艾比湖湖区周围。严重脆弱区对整个研究区生态环境变化的影响最大,主要分布于艾比湖湿地自然保护区部分区域、木特塔尔沙漠以及艾比湖湖区与阿拉山口之间的区域。总的来说,1990-2007年间,整个研究区的生态环境具有较强的脆弱性,其生态退化已接近或已超过现有社会经济和技术水平下能长期维持目前人类利用资源和社会发展的水平,而且局部区域的脆弱程度在不断加强。此外,生态脆弱度类型之间的转化比较频繁,不够稳定,近年向一般脆弱和严重脆弱等级转化的比重较大,说明研究区的生态环境总体上随时间的推移由低脆弱度向高脆弱度演进,生态环境处在不断恶化的过程中。针对艾比湖区域生态环境脆弱性现状,提出了研究区生态脆弱性分区恢复与保护的对策。对于无脆弱区,要加强艾比湖湖区和高山冰雪区的环境保护,合理利用水资源,稳定湖水面积,严禁滥挖乱采高山植物。对于轻微脆弱区,要加强艾比湖湖区周围盐渍化的防治,在干涸湖滨人工飞播盐生植物草籽,同时也可减轻大风对湖底的吹蚀作用。对于一般脆弱区,要加强水土资源的合理开发、利用与管理,土地利用要通过“以水定地”,实行“退耕还林还草”,畜牧业生产应实行“以草定畜”。对于中等脆弱区,要对流域内遭受破坏的自然植被进行恢复,在恢复的同时加强保护,防止滥砍乱伐、随意开垦和过度放牧,营造防风林。对于严重脆弱区,要依法保护好艾比湖流域的现有荒漠植被,对已遭破坏的植被进行及时有效的恢复或重建。严格控制载畜量,确保以梭梭为主的天然荒漠植被正常生长和天然更新,防止沙漠进程的加快。更多还原

【Abstract】 Presently, sustainable development is the highest aim of human beings, but population, resource and environment problems have become severe problems that human beings have faced. Rapid increasing of population and irrational using of resources has caused continuously decreasing in coordination ability of ecological system and weakening of human living condition. Through studying on ecological environment vulnerability, one of ecology’s research contents, which would play crucial role in sustainable development of ecological environment vulnerable region. The ecosystem of Ebinur Lake region has been degraded, and its ecological environment is vulnerable. During western development period, realizing and assessing essence of Ebinur Lake region’s ecological vulnerability, monitoring evolution of ecological environment and further restoration, this has great significance for sustainable development of Ebinur Lake region’s environment and economy.This paper selected Ebinur Lake region as a typical research region, used modern ecology, geography, soil erosion theory and land resources sciences& methods as a direction, exerted spatial information technology, and chose multi-temporal (1990,2001 and 2007) Landsat TM/ETM+ remote sensing images have been chosen as a basic data source. We analyzed this region’s landscape patterns and obtained landscape index, extracted research area’s soil erosion and soil salinization information, at the same time built soil erosion and soil salinization sensitivity index model. Then we built Ebinur Lake region’s comprehensive ecological vulnerability assessing model based on landscape index, soil erosion and soil salinization sensitivity index model, attained entire region’s ecological environment vulnerability distribution map, and studied Ebinur Lake region’s ecological vulnerability and its dynamic changing process. At last, we put forward the subarea restoration and protective countermeasure.Major conclusions: The research area was divided into 6 landscape patterns such as farmland, forest, grassland, water area, urban and rural construction land and unused land. Using dynamic degree model, landscape transition matrix, gravity center model and landscape index to analyze the landscape patterns of research area. The results showed that landscape patterns changed comparably in Ebinur Lake region. From the whole research period, following the rapid increasing of farmlands, urban and rural construction land, forests have increased at small scale, grasslands and water area decreased at different size. Moreover, soil desertification and soil salinization still should not be neglected. Transformation between the farmland, forest, unused land and grassland was relatively obvious, transformation between water area and unused land was more obvious. Entire moving trend of Landscape’s gravity center was towards east. This was closely related to the expanding of artificial oasis and indicated moving direction of oasis gravity center. Most dominant contribution rate of changing-in was farm land and most dominant contribution rate of changing-out was unused land. It referred that with rapid development of economy; people modulated agricultural economy structure and reclaimed a mass of abandoned land. Separated degree of urban and rural construction land was very high, which indicated that its distribution was complex and its fragmentation was high. According to the PPU index, we found that in recent 20 years, the fragmentation degree decreased, contagion degree increased gradually and connectivity of dominant patch in landscape increased too. The SqP index value of urban and rural construction land increased, and the others decreased. This indicated that the complexity of patch in main oasis body decreased.We chose three landscape pattern indexes:Landscape Isolation Index, PPU index and SqP index, at the same time we used soil erosion sensitivity index and soil solinization sensitivity index to perfect the landscape ecology assessing of research area’s ecological environment vulnerability. We built regional comprehensive ecological vulnerability model XEVI which based on ecological vulnerability index model of landscape type. It can reflect entire region’s ecological environment vulnerability from spatial aspect. Assessment result showed that the gently vulnerable area spread far and wide, and it distributed in the inner oasis which consists of Botala city, Dlite town, Belinhamudun village, Jinghe County in the west of Ebinur Lake. Non-vulnerable and light vulnerable area mainly distributed around the Ebinur Lake, periphery of the research area and partly inside the oasis. Moderate vulnerable area mainly distributed in the unused land of inner oasis and periphery of the Ebinur Lake area. Serious vulnerable area has substantial effect to ecological environment changing of entire research area, distributed in the Nature Protection Area of Ebinur Lake, Mutar desert, between Ebinur Lake and Alashankou. In conclusion, from 1990 to 2007, the ecological environment of research area was relatively strong vulnerability, and its ecological degradation has already reached or exceeded the recent level of human beings’ usage of resource and development of society, and some parts of research area’s vulnerability degree were continuously intensifying. Besides, transformation between the ecological vulnerability was relatively frequent, not enough steady. In recent years, the transformation proportion of the moderate and serious vulnerability level was relatively big. This indicated that the ecological environment of research area developed from low vulnerability to high vulnerability and ecological environment was in the situation of continuously degrading.We put forward the restoration and protection countermeasure of research area ecological vulnerability for aiming at the current status of Ebinur Lake ecological vulnerability. To non-vulnerable area, we should intensify protection of Ebinur Lake area and alpine snow-ice covered areas, rationally use water resource, stabilize the lake area and forbid destroy alpine vegetation. To light vulnerable area, we must intensify the preventing the salinization of periphery of the Ebinur Lake area, spread Halophytes’ seeds with man power to the dry lake shores, and it can alleviate gale’s erosion of lake bottom. To general vulnerable area, we have to intensify rational using and management of water resource, land use should implement "water settling land" and "Conversion of cropland to forest and grassland", and stockbreeding also should implement "grass settling livestock". To moderate vulnerable area, together with restoration of destroyed vegetation in catchment’s protection was intensified, cutting trees at random, reclamation, over-grazing should be forbidden, windbreak forests should be built. To serious vulnerable area, we should protect the present desert vegetation of Ebinur Lake catchment, forbid cutting trees and rebuild the destroyed vegetation. We should strictly control the carrying capacity, insure the normal growing and renewal natural desert vegetation which mostly contains haloxylon arnmodendron, and prevent the speed of desertification.更多还原