【作者】 卢善龙；

【导师】 陈汉林； 沈晓华； 邹乐君；

【作者基本信息】 浙江大学 ， 地质学， 2008， 博士

【摘要】 地球表层环境是在基础地质格架上演化形成的,地球深部构造格局、表层岩石类型、土壤类型等地质要素制约和影响着表层环境的发展和演化。以往研究中,除部分全球性环境变化问题外,一般的区域性环境问题研究,极少考虑基础地质要素对环境的影响,难以全面的描述和分析环境变化的成因和发展趋势。本文以金衢盆地为试验研究区,围绕区域内土地利用/土地覆被计算机自动分类、基础地质要素与环境相关性分析、综合环境评价指标建立、基础地质要素与其他环境影响要素对环境变化的影响对比分析、环境变化分析数值模型建立等专题,以Landsat TM/ETM+影像、基础地质、地形地貌、气候和社会经济等数据为基础,建立了用于综合环境分析的数值模型。首先,根据TM/ETM+影像上各多光谱波段对地物光谱的吸收和反射特性,提取了植被指数、水体指数、城镇指数和缨帽变换湿度指数等专题数据;引入定量遥感方法,从TM/ETM+热红外波段上,提取了地表温度数据;利用自行设计的影像综合分类方法,获得了研究区土地利用/土地覆被数据。其次,分析了断裂构造与地表温度、植被覆盖度和土壤湿度三个环境特征要素之间的相关性,总结了断裂、岩性和土壤等地质要素对环境变化的影响机理。第三,采用因子分析方法,获得了用于评价综合环境状况的评价指标,并对研究区1988年、2000年两个时期的环境状况作了定量评价。第四,对研究时段内基础地质、地形地貌、气候和社会经济等环境影响要素作了定量分析,对比了各要素对环境变化的影响驱动力大小。最后,建立了环境影响要素与综合环境评价指标之间的数值模型,分析了研究区未来环境的可能变化趋势。主要取得了以下5个方面的进展和结论:1)根据研究区地形地貌和地物分布特征,提出了一种基于决策树法、最大似然法、地形坡度、水体指数、植被指数和城镇指数的Landsat TM/ETM+遥感影像综合分类方法。方法以决策树为基础,利用地形坡度数据,消除了由于地形坡度引起的林地和耕地之间的同谱异物现象;使用水体指数、植被指数和城镇指数,提取了水体、耕地、山区裸露地;采用最大似然法,区分了城镇用地和盆地区裸露地。2)针对研究区断裂系统地表温度场分析,提出了基于均值统计运算的分段均值法。方法根据距离断裂带的远近,将断裂带两侧一定区域作等间距划分,通过统计不同等分带平均地表温度的变化,获得地表温度场的分布特征和各断裂带对地表温度场的大致影响宽度。研究认为,在特定范围内,距离研究区各断裂带越近,地表温度越高;研究区江山-绍兴断裂带、球川-萧山断裂带、常山-漓渚断裂带、淳安-温州断裂带、松阳-平阳断裂带和衢州-天台断裂带对地表温度场的大致影响宽度分别为16km、3km、5km、11km、4km和13km。3)依据热红外遥感影像上热异常具有特征几何尺寸的特点,提出了基于尺度分析的热红外遥感热异常信息增强方法。研究中,方法有效地降低了背景干扰信号,突出了来自地下的热异常信息,获得了研究区热异常平面分布形态和特征:地表热异常沿断裂带分布较为突出,呈线性特征,主要沿北东走向的江山-绍兴断裂带和常山-漓渚断裂带两侧分布;在淳安-温州断裂带与衢州-天台断裂带交叉位置,热异常特征明显。4)分析总结了断裂、岩性和土壤对环境的影响机理。研究区各深、大断裂带周围,岩石破碎程度高,沿着断裂破碎带向上传导的地下热流,在地表形成热异常区域,影响地表热环境。不同岩石类型的风化方式和成土特性,影响土壤类型和特点、地表生境的复杂及困难程度、水文特性等,在地质基础方面对环境产生巨大影响。土壤因母岩的结构和成分的差异,具有不同的孔隙度、厚度和侵蚀特性,形成不同的湿热环境,影响地表植被生长。5)利用因子分析方法,分析了反映自然生态环境、地表热环境和农业环境的植被指数、地表温度和土壤湿度三个环境特征要素,获得了用于评价综合环境状况的评价指标。并用该指标定量评价了研究区1988年至2000年这13年中环境的变化状况:研究区环境发生了较大的变化。整体而言,环境逐渐好转。但环境相对较差的区域,由丘陵山地区域向盆地区域转移。6)对比分析了基础地质、地形地貌、气候和社会经济要素对研究区环境变化的影响驱动力大小,建立了环境影响要素与综合环境评价指标之间的数值关系模型。分析结果表明,研究时段内,引起研究区环境变化的主要原因是区域气候的变化,其次是基础地质和地形地貌因素的影响,再其次是社会经济的发展变化。在一个较短的时间内,基础地质和地理环境相对稳定,环境易受土壤侵蚀、蒸发量、降水量、气温、年末总人口和国内生产总值等要素的影响。更多还原

【Abstract】 The formation and the evolution of the earth’s surface environment are based on the basic geological structural pattern.The geological structures in the deep earth,lithology of the land surface,and the soil types will restrict and influence the development of the environment. However,for the global or regional environment problems,few studies considered the influence of the geological factors.In this paper,focused on the topics of land use/cover image classification,relation analysis between the basic geological factors and the environment, integrated environment evaluation index(IEEI) creation,environment change driving force comparison among different influencing factors,numerical environment modeling,and so on, taken Jinqu basin,located in Zhejiang Province of China,as the case study area,and used Landsat TM/ETM+ images,basic geological data(fault,lithology,and soil),topographical data (DEM and slope),meteorological data(rainfall,evaporation and temperature),and social-economical data(population and GDP),a numerical model for integrated environment analysis was introduced.At first,the NDVI(Normalized Difference Vegetation Index),NDWI (Normalized Difference Water Index),NDBI(Normalized Difference Build-up Index) and tasseled cap transformation wetness was extracted,according to the spectral characteristics of each multi-spectral band of the TM/ETM+ images;the land surface temperature(LST) was calculated from the thermal infrared band of the TM/ETM+ images;and the land use/cover types was classified by using the integrated classifier that designed by the author.Secondly,the relation between the faults and the environment indicating factors(NDVI,LST,and soil moisture) was analyzed,and the influencing mechanism of the geological factors to the environment change was summarized.Thirdly,an integrated environment evaluation index (IEEI) that can be used to evaluate the conditions of the environment was obtained,by using the factor analysis;the environment conditions of the study area on 1988 and 2000 were quantitatively evaluated.Fourthly,the change of the environment influencing factors,including basic geological factors,topographical factors,meteorological factors,and social-economical factors were quantitatively analyzed,and their driving force to the environment change was compared.Finally,a numerical model between the environment influencing factors and the IEEI was created,and the trend of the environment change in the near future was analyzed.The main evolves and results are like follows:1) An integrated classification method for Landsat TM/ETM+ images that combined decision tree with maximum likelihood classifier,slope,NDWI,NDVI and NDBI was introduced,according to the distribution characteristics of the topography,geomorphology and land surface objects.In the study,the integrated classifier taken the decision tree as basic classification algorithm,reduced the phenomena of objects with similar spectrum between the vegetations of living on forest and agricultural land,by using the slope data;extracted the water,agricultural land,and mountainous bare land,with the ancillary data of NDVI,NDWI and NDBI;and distinguished urban and bare land on plain,by using the maximum likelihood classifier.2) The Subsection Mean Method(SMM) based on the mean statistic algorithm was introduced,in allusion to the land surface temperature field analysis of the fault system.It chooses a given area on both sides of the fault as the analysis area,partitions the area into numbers of parts according as the distance to the fault,calculates the mean land surface temperature(LST) and the mean distance of each subsection,and plots the correlation curve of the mean LST and the mean distance.Then obtain the rough influencing width of the fault to the land surface thermal field on the correlation curve.The results indicated that,the nearer to the faults of the study area,the higher is the LST.And the rough influencing width of Jianshan-Shaoxing fault,Qiuchan-Xiaoshan fault,Changshan-Lizhu fault,Chun’an-Wenzhou fault,Songyang-Pingyang fault,and Quzhou-Tiantai fault is 16,3,5,11,4,and 13 kilometers, respectively.3) A thermal infrared anomaly characterization method based on scale analysis was introduced,according to the characteristics of the object,including thermal anomaly represented by pixel or pixel congregations on the thermal infrared remote sensing image,that it has special geometric scale.It effectively reduced the background interference information, enlarged the thermal anomalies from the subsurface,and objectively characterized the planar distribution shapes and characteristics of the thermal anomalies around the faults of the study area:The anomalies were linearly distributing along both sides of Jiangshan-Shaoxing fault and Changshan-Lizhu fault,and were concentrating upon the intersectional area of Chun’an-Wenzhou fault with Changshan-Lizhu fault and Quzhou-Tiantai fault.4) The influencing mechanism of the geological factors to the environment was analyzed and summarized.In the study area,the thermal flow transmitting from the subsurface,along the faults,result in land surface thermal anomaly,and influence the land surface thermal environment.The weathering pattern of the lithology influences soil types and their features, complexity and difficulty of the land surface ecological environment,and hydrological features. So the lithology greatly influences the environment on the basic geological conditions. Moreover,due to the structures and components of the mother rocks,the soils with different cavity,thickness,and weather feature result in different moisture and temperature conditions for vegetation living.5) Three thematic data of NDVI,LST and soil moisture that can reflect the natural ecological environment,land surface thermal environment,and agricultural environment was analyzed,and the IEEI that can be used to evaluate the integrated environment was obtained, by using the factor analysis.The comparison result,between the two indices of 1988 and 2000, indicated that the environment of the study area suffered great change.Holistically speaking, the integrated environment was getting better.But,the relatively worse area was transferring from the mountainous area to the plain.6) The driving force of the basic geological factors,topographical factors,meteorological factors,and social-economical factors to the environment was compared,and a numerical relation model between the environment influencing factors and the IEEI was created.The results indicated that,during the study period,the primary reason of influencing the environment is the climate change.The second reason is the geological and topographical evolution.And the third reason is the social-economical development.In a short time period, the basic geological and geographical environment is relatively stable,so the environment will be easily influenced by the factors of soil erosion,evaporation,rainfall,temperature, population and GDP.更多还原