陇中黄土丘陵沟壑区生态系统健康评价

【作者】 张岑；

【导师】 任志远；

【作者基本信息】 陕西师范大学 ， 自然地理学， 2008， 硕士

【摘要】 随着现代科学技术高速发展和全球经济的高速增长,人类正以前所未有的规模和强度影响环境,破坏和改变自然生态系统,致使生态系统的健康受到越来越大的损害,并由此危及到人类自身,引起了人类的普遍关注,生态健康和生态安全成为学者研究的热点问题。陇中黄土丘陵沟壑区在历史上曾经森林繁茂、山清水秀,但随着人类的过度开垦,植被破坏和水土流失的局面与日俱增,使该区已成为世界上水土流失最严重的地区,也是我国生态环境最脆弱的地区之一。因此,从陇中黄土丘陵沟壑区巨系统出发,综合研究把握该区域生态系统健康状态,探索与实践生态健康的研究理论与方法,不仅有重要的的科学意义,对政府部门把握黄土高原丘陵沟壑区生态系统健康的变化并及时做出控制和治理措施也具有十分重要的应用价值。本研究以榆中县为例,以生态系统健康理论为基础,将研究区生态系统的结构和功能结合起来,基于遥感影像、DEM和调查数据,在野外实地调查验证的基础上,采用“3S”技术,生成各参评因子的专题栅格图层。运用层次分析法,从影响生态系统健康的自然和人文因子的角度出发,选择活力、组织结构、负荷能力、恢复力、生态系统功能维持、外部输入及人群健康状况作为研究区生态系统健康评价的7个要素,构建了生态系统健康评价指标体系,评价该地区生态系统健康状况并探讨该地区生态系统健康的时空差异。通过深入科学、综合研究得出以下重要成果和结论:(1)主要生态系统健康评价因子的变化特征:①土地利用变化研究区土地总体利用状况主要以耕地居多,其次是草地,然后是林地。最少的土地利用类型,1991年为园地,2002年和2006年为水域。榆中县1991年到2006年土地利用的变化情况是:耕地、水域和未利用地面积持续减少;林地、园地和交通建设用地面积不断增加;草地先减少后增加。②生态系统有机质生产变化生态系统有机质生产物质总量1991年为1659476.45吨,2002年1479552.75吨,2006年1497894.53吨。③自然生态服务功能生态系统植被土壤保持量1991年为2112431.82吨,2002年2014629.39吨,2006年2081419.39吨。植被涵养水源量1991年为6990337.007吨,2002年为7334867.2吨,2006年7344755.83吨。生态系统固碳量1991年为2704946.6吨,2002年为2411671吨,2006年2441568.1吨。植被释放氧气量1991年为1991371.74吨,2002年1775463.3吨,2006年1797437.4吨。(2)生态系统健康状况1991年生态系统健康平均指数为0.4725,区域生态健康最低指数为0.2912,最大指数为0.7119;2002年生态健康平均指数为0.44304,区域最低指数为0.2655,最大为0.7115;2006年平均为0.443889,区域最低指数0.2733,最高为0.7116。1991-2006,榆中县生态健康状况基本处于中度健康状态,2002年生态系统健康状况比1991年有所下降,从2002年到2006年又略显上升。本研究在以下方面有一定的进展和创新:(1)根据黄土丘陵沟壑区客观状况,考虑到人类胁迫对生态系统健康影响,从自然和人文因子角度出发,在遵循评价指标选择原则的基础上,构建了黄土丘陵沟壑区生态系统健康评价指标体系。(2)利用3S技术,提取了陇中黄土丘陵沟壑区生态系统健康评价各指标因子,较为科学准确地反映研究区生态健康状况。(3)评价方法上,在汲取前人研究成果的基础上,对生态系统健康评价模型进行了客观修正,并对评价指标因子进行反复提炼,运用多种生态服务功能反映生态系统健康评价中的服务功能,克服了用单一因子评价服务功能的局限性。(4)运用各参评因子的专题栅格图层,在GIS和RS强大的图层叠加和模型运算功能支持下,完成生态系统健康评价的结果。更多还原

【Abstract】 With the development of the modern science technology and the global economic growth, the human being are influenceing the environment, changeing and destroying the natural ecosystem at an unprecedented scale and intensity. As a result, the ecosystem health is dameged more and more, the humankind is also endangered and now it is putting a common attention to the environment. The ecological health and the ecological security become the hot topics of the scholars studies. In the history , the Longzhong loess hill gully area was covered with luxuriant forest and had a beautiful scenery . However ,with the humanitys excessive reclamation and extensive cultivation ,the vegetation was destroyed and aggrevated, So that the area has become the world’s most serious soil erosion areas.And it is also one of the frailest ecological areas in our country . So in this article ,it did a synthetic research on the condition of the ecosystem health from the great system of the Longzhong loess hill gully area and then explorated and practiceed the research theory and method about the ecology health. This has not only the vital scientific significance, but also the very important applied value by which the government could grasp the changes of the ecosystem health about the Loess Highlands hill gully area and take measures on time according to it.In this article ,it taked the research of Yuzhong area for example , combined the ecosystem’s structure and function together on the basis of ecosystem health and formated the topic raster layers of each evaluation factors based on the remote sensing images, the DEM , the field survey datas and the 3S techonology . In the view of the natural and human elements that effected the ecosystem health,used the AHP ,and choosed six evalution factors of the ecosystem health—vigor , organizational structure , capacity , resilience, the ecosystems maintenance functions ,and the external input and human health as evaluation based on the principles in choosing evaluation factors . The article constructed the ecosyetem health status system , evaluated the condition of ecosyetem health and explored the region’s ecosystem health differences in time and space.This article drawed the following conclusions and important results through in in-depth scientific and comprehensive study.1) the changeable characteristics of the principal ecosystem health evaluation①Land-use changeCultivated land was a major general in YuZhong,that was followed by the grass land,the least type of land : garden plot in 1991, water land in 2002 and in 2006 .②The organic production of ecosystem . The total of the organic production of ecosystem was 1659476.45 tons in 1991, 1479552.75tons in 2002, tons 1497894.53 in 2006.③Natural ecosystem servicesSoil conservation of vegetation ecosystem was 2112431.82 tons in 1991, 2014629.39 tons in 2002, 2081419.39 tons in 2006. Vegetation conserving water was 6990337.007 tons in 1991, 7334867.2 tons in 2002,7344755.83 tons in 2006. Absorption of carbon dioxide of ecosyetem was is 2704946.6 tons in 1991, 2411671 tons in 2002, 2441568 tons in 2006. Releasing oxygen of ecosyetem was 1991371.74 tons in 1991,1775463.3 tons in 2002, 1797437.4 tons in 2006. 2) Ecosystem healthThe average index of ecosystem health is 0.4725,the lowest index of region ecosystem health is 0.2912,the highest index is 0.7119 in 1991 .The average index of ecosystem health is 0.44304, the lowest index of region ecosystem health is 0.2655, the highest index is 0.7115 in 2002. The average index of ecosystem health is 0.443889, the lowest index of region ecosystem health is 0.2733, the highest index is 0.7116. From 1991 to 2006 ,the situation of ecosystem health in Yuzhong was in the moderate health level. There is an significantly decling ecosystem health in 2002 than in 1991, an significantly increase in 2006 than in 2002.The regional of ecosystem which are over health standards (>0.6) distributed in Xinglong mountain and Maxian mountain. The regional of ecosystem which are moderately health(0.4-0.6) are the most extensive,there were Yinshan ,Shangzhuang, north of Mapo and the most area of Xinying,jinya,Laizibao,Xiaguanying of Central ward region ,lujiagou,Yuanzicha,Qincheng of the northern mountains region. Ecosystem health for the general disease (0.2-0.4) of the region mainly distributed in Gaoya,Sanjiaocheng,Qingshui,Gancaodian of Central Ward region,Shanghuacha,Gong -jing,Kaiping of the northern mountains region. Most of the regional ecosystem health condition has declined, the rural ecological health of individual performance increased slightly, from the whole entire study area, the ecosystem health showed declining trend, from 1991 to 2006, in Yuzhong.There are some progression and innovation in the article as follows:1) The article builds the ecosystem health assessment index system about the loess hill gully area, according to the Loess Plateau area of objective conditions and taking into account the human stress on the ecosystem health effects from natural and human factors point of view.2) The article extracts the evaluation of ecosystem health indicators factor in the Loess Plateau District by 3S ,which could reflect ecological health more accurately.3)In the evaluation methods aspect,it ameliorats the evaluation model of the ecosystem health objecti -vely, learning from the predecessors in the research results. It also overcoms a single factor evaluati -on services limitations by using the value of the ecosystem service function to reflect the service function of ecosystem health evaluation.4) Using the topical raster layers of evaluation factors, the article accomplishs the evalution of ecosystem health on the support of the GIS and RS which have powerful functions in layer staking and mode arithmetic.更多还原