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合成孔径雷达干涉测量技术（InSAR）及其对城市遥感的意义 总被引：2，自引：0，他引：2
该文详细论述与分析了合成孔径雷达干涉测量（InSAR)的干涉几何特征及InSAR影像之间的相关性特征，着重阐述并分析了影响其地学监测方面的数据质量等相干技术问题，就InSAR开展上海城市地面沉降研究提出了基本思路，对InSAR城市遥感应用的潜在意义进行了分析和讨论。 相似文献
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吉林省西部地表蒸散与土地利用/覆盖变化关系 总被引：2，自引：0，他引：2
地表蒸散作为地表水分平衡和能量平衡的重要组成部分,是土地利用/覆盖变化的一个关键驱动因素。地表蒸散量的大小影响土地利用变化过程;反过来,土地覆盖类型又控制地表蒸散量的大小。为了弄清它们之间的相互作用关系,揭示地表蒸散在生态环境变迁中的作用,基于地表能量平衡理论,计算了研究区1986、1996和2000年的蒸散量,并与对应年份的不同土地类型数据进行了叠加分析。结果表明,从1986年到2000年,研究区草地、沙地和盐碱地的蒸散量都在变大,其中以沙地蒸散量增长最快,草地次之,盐碱地增长最小,为土地类型向盐碱地和沙地转化提供了有利条件,在一定程度上说明了地表蒸散加剧了研究区生态环境恶化。 相似文献
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为了实现对呼和浩特市城区形变监测,采用永久散射体合成孔径雷达干涉测量（PS-InSAR）技术,对2017年3月—2021年4月期间25景呼和浩特市城区Sentinel-1A数据进行时序干涉处理,提取了城区地表沉降信息,并分析了主要沉降中心沉降原因。结果表明：呼和浩特市城区地表存在5个明显的沉降中心,整体地表平均年沉降速率3.65 mm/a,平均累计沉降量为15.50 mm,其沉降主要原因是由于地下水过度开采。Sentinel-1A数据具有时间基线短、影像数量足、数据免费等优点,利于InSAR时序分析,可满足同类城区地表形变监测工作,服务城市安全。 相似文献
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D-InSAR技术在地面沉降监测中的应用 总被引：2，自引：0，他引：2
重复轨道差分干涉测量(D-InSAR)技术在监测地表形变方面得到了深入的研究和广泛的应用。本研究将时间序列分析方法引入到差分干涉测量技术中,并和永久散射体技术相结合,提出一种基于PS点的差分干涉时间序列分析方法。该方法以干涉图上两个较近PS点的相位差为研究对象,能够消除大气相位延迟对差分干涉处理的影响。并将该方法应用在天津地面沉降监测实验中,获得了天津地区地面沉降数据和沉降分布图,取得了比较满意的结果。 相似文献
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合成孔径雷达干涉测量(InSAR)技术是传统的合成孔径雷达技术和射电天文学中的干涉测量技术相结合而发展起来的一项新的遥感技术,这一新技术以其在大范围地表高程测量和地表变形测量方面所具有的独特优势和巨大潜力,而成为对地测量和地学科学研究的一个重要的工具。同星载InSAR相比,机载InSAR在高分辨率区域测图方面具有较大的优势,而且数据采集的时间安排及飞行方位选取方面相对较灵活。而且SAR是一种主动微波遥感技术,具有全天时全天候的工作特征,这一技术也正在成为中国西部困难地区测图的一个非常有效的工具。在详细分析应用机载InSAR数据测量地表高程的基本原理的基础上,提出了机载InSAR自动生成DEM的技术流程,并以内蒙古丰镇地区的机载InSAR数据为基础进行了试验研究,取得了较好的效果,为这一新技术的进一步实际应用奠定了基础。 相似文献
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马博朱杰勇刘帅杨得虎 《地质灾害与环境保护》2023,(3):8-14
目前合成孔径雷达干涉(interfermoetic SAR,InSAR)理论与技术一直处于快速发展态势,在地质灾害隐患识别方面已有阶段性的进展,但是为了提高识别的效率与准确度还需进一步的研究。因此提出一种联合时序InSAR(Interfermoetic SAR)技术和滑坡灾害易发性的方法对云阳县进行滑坡灾害早期识别。该方法通过小基线集干涉测量(Small Baseline Subset InSAR, SBAS-InSAR)技术获得该地区地表形变信息,再结合通过信息量模型以地貌类型、土地利用类型、断层距离、高程、工程地质岩组、坡度、坡向、曲率与河流距离9个评价因子作为信息量值获得的滑坡灾害易发性区划与谷歌影像分层次进行潜在滑坡灾害的识别。然后对识别结果进行验证,研究表明了该种方法在此地区应用的可行性,且研究成果为地质灾害进一步的调查提供了参考与技术支持。 相似文献
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探地雷达技术对表层岩溶带典型剖面组构刻画与界面识别 总被引：1，自引：0，他引：1
表层岩溶带是岩溶研究的重要对象,以往研究以剖面调查半定量为主,文章利用探地雷达属性技术对其发育情况进行定量研究。选取3个表层岩溶带的典型剖面（浅裂隙土、深裂隙土、厚土层覆盖）,并采集探地雷达数据,通过提取相干体属性和均方根振幅属性来挖掘雷达数据中的潜在信息,用于区分介质组构和识别发育深度界面。结果表明,均方根振幅属性较好地区分出了浅裂隙土型和深裂隙土型的岩土介质,厚土层覆盖型的犁耕层与非犁耕层土壤介质;相干体属性能较好地识别出表层岩溶带和下部完整基岩,定量化其发育厚度。 相似文献
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黑河流域中游张掖绿洲景观格局研究 总被引：35，自引：2，他引：33
在解译的张掖绿洲土地利用/土地覆盖图的基础上, 进行相关的景观类型综合处理, 计算了绿洲景观格局的多个指数. 结果表明, 绿洲景观的组成以戈壁、沙地、耕地和草地为主, 体现了荒漠基质受人工影响而形成的典型农业型绿洲的特点. 绿洲内居民点众多, 仅与少数类型邻接并且比较分散, 戈壁、平原旱地和沙地分布则比较集中. 盐碱地和裸岩石砾地的形状最复杂, 戈壁的形状则最简单; 同时, 平原旱地、戈壁和裸岩石砾地的连接性均较好, 在景观中占有较大比重, 类型间的物质和能量迁移比较通畅. 相似文献
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青木关岩溶槽谷流域不同土地利用类型土壤可蚀性分析 总被引：2，自引：0，他引：2
基于土壤实地采样和理化性质测试分析,采用EPIC模型K值计算方法,分析青木关岩溶槽谷流域的土壤理化性质、土壤可蚀性及其影响因子。结果发现:（1）青木关岩溶槽谷流域表层土壤（0~10 cm）可蚀性K值介于0.037 1~0.060 5之间,均值为0.048 5,中值为0.047 5,变异系数为10.71%,偏度和峰度值小于1;（2）表土机械组成中以粉粒含量为主,土壤质地属于粉壤土;有机质含量在13.98~52.24 g.kg-1之间,均值为29.20 g.kg-1;表土可蚀性K值与砂粒含量、有机碳含量呈极显著负相关,与粉粒含量呈极显著正相关,与黏粒含量呈负相关;（3）不同土地利用类型下的表土可蚀性K值以裸土地最大,为0.058 3,耕地次之,为0.053 4,其次为园地、荒草地和竹林,分别为0.048 3、0.047 8和0.046 9,针阔叶混交林最小,为0.0427,分别存在显著差异（P＜0.05）,变异系数介于2.7%～6.1%之间;受人类活动影响强烈的裸土地和耕地是本地区主要的泥沙策源地,恢复植被能有效提高土壤抗蚀能力;（4）不同土地利用类型土壤剖面K值均值为耕地（0.056 3）显著大于荒草地（0.051 6）与林地（0.048 1）（P＜0.05）,荒草地与林地K值间差异性不显著;K值剖面分布一致表现为0~35 cm相对较小且变化较大,土下35~60 cm随着深度的增加而增大。 相似文献
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云南小江流域不同土地利用类型土壤微量元素的对比分析 总被引：1，自引：0，他引：1
文章对云南小江流域不同土地利用类型（耕地、林地、园地、建设用地、裸地）土壤的微量元素进行空间插值、方差分析和相关性研究,旨在探讨云南小江流域不同土地利用类型微量元素的分布和迁移规律。结果表明:除Mo的含量较低外,小江流域土壤中Cu、Mn、Ni和Zn的含量普遍较高。各微量元素含量在不同土地利用类型中具有明显的差异性,园地土壤微量元素含量最高。微量元素的变异程度均属于中等变异。Cu、Mn、Mo、Ni、Zn的空间分布具有一定的相似性,高值区主要集中在海拔较低的岩溶河谷区右侧和盆底沉积平坝区,主要土壤类型为碳酸盐岩红壤;低值区集中在海拔较高的河谷区左侧和中山区,主要土壤类型为碎屑岩。地貌、土壤母岩和人为活动是影响微量元素分布和迁移的重要因素。 相似文献
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基于遥感影像的决策树分类,结合土地利用图,将北京市农业地表覆盖划分为春玉米、冬小麦、果园、林木苗圃、牧草地、设施农业和畜禽饲养地。考虑海拔、坡度和土壤质地三个因子将北京市分成10个景观区,在景观分区和不同农业用地基础上划分出39类农业景观单元。利用基于遥感影像计算的归一化差异植被指数,结合实地调查验证,分类出北京市冬春季裸露农田。结合景观分类,分析了不同景观单元冬春季地表裸露情况。结果表明：2007—2008年冬春季裸露农田共8.05×104 hm2,主要分布在延庆盆地、密云水库北岸和城区边缘的近郊农业区;海拔和土地利用方式对裸露情况影响较大,其中山区春玉米和平原果园裸露情况绝对面积较大,分别占到总裸露农田面积的40%和17%,牧草地、林木苗圃与设施农业地裸露程度较高。基于不同景观单元裸露程度,结合绿肥种植、保护性耕作、生草覆盖等裸露农田治理方法,探讨了北京市农业产业和景观一体化建设策略。 相似文献
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The relations between land use and karst rocky desertification in a typical karst area,China 总被引：13，自引：0，他引：13
Karst rocky desertification (KRD) is one major type of desertification which is under irrational human impact on the vulnerable
eco-geo-environment. In this study, Zhudong fengcong rocky desertification landscape was selected to investigate the land
use types distribution law in different rock types and the KRD land in different land use types. KRD data was determined by
user–computer interactive interpreting method from Aster images in 2004, according to the exposed ratio of rock, the coverage
of vegetation and soil in 0.2 km2 unit, integrating with land utilizing present situation map, hydrogeology map, relief map, vegetation map, soil distribution
map, as well as the practical investigation and the population census datum in 2002. Results showed that the occurrence ratio
of KRD land is different in land use types and rocky assemblages obviously; land cover has a strong impact upon KRD. The sloping
cropland distributed in homogenous limestone has a higher occurrence ratio of light KRD, secondly, is in the limestone interbedded
with clastic rock. Light KRD land was dominated by shrubland, and sloping cropland accounts for 11.67% of it, moderate KRD
land was dominated by moderate coverage grass slopes, strong and extremely strong KRD was dominated by rocky dry land which
is difficult to use. 相似文献
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青藏高原多年冻土区活动层土壤入渗特征及机理分析 总被引：1，自引：0，他引：1
青藏高原多年冻土区活动层土壤的入渗规律研究是高寒区土壤水循环过程研究的主要内容。以青藏高原多年冻土区高寒沼泽草甸、高寒草甸和高寒草原的活动层土壤为研究对象,裸地为参照对象,分析了不同植被类型土壤的入渗规律及其主要影响因子。结果表明：不同植被类型土壤的入渗能力排序为高寒草原>裸地>高寒草甸>高寒沼泽草甸。高寒草甸土壤中致密的根系对土壤水分的运移具有强烈的阻滞作用,降低了土壤的入渗性能,而高寒草原土壤层根系较为稀疏,对土壤入渗的阻滞作用较弱,土壤水分向深层的渗漏速率较大。通过对比4种土壤入渗模型的模拟结果,发现Horton模型更适用于描述高寒草地土壤水分的入渗过程。另外,不同入渗模型对裸地入渗过程的模拟均优于其他植被类型草地,说明植被类型及植物的生长状况影响土壤入渗过程的模拟效果。全球变暖条件下,多年冻土区土壤入渗研究将为青藏高原多年冻土区陆地水文过程模型提供参数支持,为未来水资源变化研究提供基础数据。 相似文献
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The impact of land use and land cover changes on soil moisture and hydraulic conductivity along the karst hillslopes of southwest China 总被引：4，自引：1，他引：3
The understanding of the temporal and spatial dynamics of soil moisture and hydraulic property is crucial to the study of
several hydrological and ecological processes. Karst environments are extremely fragile because of thin soil and small soil
water holding capacity. A marked intensification of agricultural land use and deforestation due to increase of population
and thus expansion of agricultural areas has made the karst environment even more delicate. In this study, the soil moisture
contents (SMC) and hydraulic conductivities (K) along four karst hillslopes were measured in situ by time domain reflectometry and the Guelph Permeameter, respectively,
at test plots, each of which has a different vegetative cover, landform, land surface slope, soil property and content of
rock fragment. The statistical results from the measurements show that land cover changes strongly affect the distribution
of soil moisture and hydraulic properties. Compared with SMC in the bare soil areas, SMC values are 30.5, 20.1 and 10.2% greater
in the forest, shrub and grass areas, respectively. Vegetation roots significantly increase permeability of low-layer silt
soils. Measured K values were 0.8, 0.6 and 0.01 cm/min for the forest, agriculture and bare soil areas, respectively. When the forest was destroyed
by fire or cut to become an agricultural area or bare soils, SMC would be reduced by 13.1 and 32.1%, respectively. If deforestation
leads to strong rock desertification, SMC was reduced by 70%. Bedrock fractures significantly reduce the SMC in the overlying
layer, but increase K values. SMC values of 30–45% would be reduced to 17–30% for the soil layer embedding rocks with and without fractures, respectively.
K values could be increased from 1.0 to 8.5 cm/min. SMC are sensitive to terrain. A slope angle increase of 1° would reduce
SMC about 0.82%. These changes resulting from land cover and land use alterations offer useful information to further investigate
the response of ecosystem evolution to hydrodynamic processes. 相似文献
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Spatio-temporal evolution of rocky desertification and its driving forces in karst areas of Northwestern Guangxi, China 总被引：6，自引：1，他引：5
Qing-qing Yang Ke-lin Wang Chunhua Zhang Yue-min Yue Ri-chang Tian Fei-de Fan 《Environmental Earth Sciences》2011,64(2):383-393
Rocky desertification (RD) is a process of land degradation that often results in extensive soil erosion, bedrock exposure and considerable decrease of land productivity. The spatio-temporal evolution of RD not only reflects regional ecological environmental changes but also directly impacts regional economic and social development. The study area, Hechi, is a typical karst peak cluster depression area in southwest China. Remote sensing, geographic information systems (GIS) and statistical techniques were employed to examine the evolution, including the identification of driving forces, of karst RD in the Northwestern Guangxi. The results indicate that RD became most apparent between 1990 and 2005 when areas of various types of RD increased. Within the karst RD landscape, slight RD was identified as the matrix of the landscape while potential RD had the largest patch sizes. Extremely strong RD, with the simplest shape, was the most influenced by human activities. Overall the landscape evolved from fragmented to agglomerate within the 15-year timeframe. Land condition changes were categorized as five types; desertified, recovered, unchanged, worsened, and alleviated land. The largest turnover within the RD landscape was between slight and moderate RD. With regards to the driving forces all RD had been increasingly influenced by human activities (i.e., the stronger the RD, the stronger the intensity of human disturbances). Dominant impact factors of the RD landscape had shifted from town influence and bare rock land in 1990 to bare rock and grassland in 2005. Moreover, the impacts of stony soil, mountainous proportion and river density on RD increased over time, while that of others decreased. The significant factors included human activities, land use, soil types, environmental geology, and topography. However, only anthropogenic factors (human activities and land use) were reported as leading factors whereas the others acted simply as constraining factors. 相似文献
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Gobi is one of the most important landscapes in northwest China, and it is also one of the dust sources in north China and even in central Asia. Based on the different land surface characteristics on the gobi surface, sand and dust emission process and mechanism are obviously different with other landscapes, such as sandy desert. Dust emission process and mechanism on the gobi surface were analyzed in this paper. Wind power system, geomorphology pattern and underlying characteristics were considered for their effect on the sand and dust emission process. Then, the mechanism of land surface characteristics on threshold wind velocity was analyzed. Finally, based on the previous studies on dust emission and mechanism, and in combination with the regional and global requirement, we suggested that the land surface characteristics parameterization, identification of the dust sources and sediment emission mechanism should be the main issues in the future gobi sand and dust research. 相似文献