Development of the models to estimate particulate matter from thermal infrared band of Landsat Enhanced Thematic Mapper

Particulate matter concentration and assessment of its movement pattern is crucial in air pollution studies. However, no study has been conducted to determine the PM₁₀ concentration using atmospheric correction of thermal band by temperature of nearest dark pixels group (TNDPG) of this band. For that purpose, 16 Landsat Enhanced Thematic Mapper plus ETM+ images for Sanandaj and Tehran in Iran were utilized to determine the amount of PM₁₀ concentration in the air. Thermal infrared (band 6) of all images was also used to determine the ground station temperature (GST b6) and temperature of nearest dark pixels group. Based on atmospheric correction of images using temperature retrieval from Landsat ETM+, three empirical models were established. Non-linear correlation coefficient with polynomial equation was used to analyze the correlations between particulate matter concentration and the ground station temperature for the three models. Similar analyses were also undertaken for three stations in Klang Valley, Malaysia, using 11 Landsat ETM+ images to show the effectiveness of the model in different region. The data analysis indicated a good correlation coefficient R = 0.89 and R = 0.91 between the trend of the result of temperature of nearest dark pixels group b6 ? (GST b6 ? GST) model and the trend of PM₁₀ concentration in Iran and Malaysia, respectively. This study reveals the applicability of the thermal band of Landsat TM and ETM+ to determine the PM₁₀ concentration over large areas.     

多源遥感数据在西准噶尔哈拉阿拉特山地区1:5万地质填图中的对比研究

以ETM、SPOT5和Quickbird为主要信息源,在哈拉阿拉特山地区开展1:5万区域地质填图,对该地区的地层单元、中—小规模地质体(如岩脉、小岩体和火山口)和地质构造特征进行了详细地遥感解译分析,并开展了大量的遥感野外地质调查验证.结果表明,采用彩色空间HSV变换融合法将SPOT5高精度遥感图像数据与ETM图像数据...     

Characterizing spatiotemporal dynamics of land cover with multi-temporal remotely sensed imagery in Beijing during 1978–2010

To facilitate urban planning and management in fast-growing metropolitan areas, it is highly necessary to detect the spatiotemporal changes of different land cover types. This study aimed at identifying Beijing’s land cover types and detecting the characteristics of their spatiotemporal changes using time series remote sensing and GIS techniques from 1978 to 2010. A total of 16 Landsat MSS/TM/ETM+ images were collected during the spring and late summer seasons. After preprocessing the dataset, artificial neural network was used to perform the land cover classification. Consequently, four maps were generated for 1978, 1992, 2000, and 2010, with six classes (agriculture, woodland, grassland, water, urban, and barren land) according to the level I classification scheme. Three transition matrices were constructed to represent all possible changes that occur in the landscape. The results showed that agriculture, barren land, and grassland had an increase in area, while urban, water, and woodland had a reduction within the study area. A total of 2,032.341 km² agriculture was reduced and 2,359.146 km² woodland was increased. In the three periods for 1978–1992, 1992–2000, 2000–2010, agriculture had the largest amount of transfer out primarily to urban class around central urban areas and woodland had the most transfer in mainly from barren land in mountainous areas. More importantly, the driving forces analysis including economic development, growth of population and construction areas, and institutional policies was conducted to find out the primary factors inducing the land cover change.     

1964-2010年青藏高原长江源各拉丹冬地区冰川变化及其不确定性分析

利用1964年美国CORONA间谍卫星影像和1976-2010年的Landsat MSS/TM/ETM+遥感影像, 对青藏高原长江源各拉丹冬地区的冰川进行监测, 获得每10 a间隔的冰川面积数据, 并对冰川制图中的不确定性进行了评估.由于冰川表面比较洁净, 认为该地区冰川变化的不确定性主要由分辨率(Landsat)和人为操作差异造成, 误差可达1%~2%.通过对比发现: 1964-2010年间, 各拉丹冬地区冰川面积总体上减少了45.75 km², 相对变化为6.80%, 冰川年平均变化速度约为0.99 km²·a^-1, 相对变化速度为0.15%·a^-1; 该地区冰川总体退缩较为缓慢, 但部分冰川变化显著, 在138条冰川中, 有14条大冰川存在较为明显的变化.在过去的近50 a中, 该地区的冰川并不是都呈退缩状态, 先后有9条冰川出现过前进的现象, 其中有1条冰川一直处于前进状态, 长江源头冰川(姜古迪如北支冰川)先后出现过两次前进, 分别发生在1964-1977年间和2000-2010年间.     

基于整数小波和非负有序独立成分分析的遥感影像融合

结合ICA算法可以去除高阶冗余信息和IWT具有多分辨率、运算速度快的特性,在非负性条件的约束下,提出一种基于整数小波变换和非负有序独立成分分析(IWT-ONICA)的遥感影像融合方法。将该方法用于全色影像和多光谱影像的融合,数理统计(峰值信噪比、扭曲度、熵等)和目视判读结果表明,该方法融合效果优于其他方法,融合结果更加清晰,可视性更好。     

基于遥感技术的近40a来敦德冰川变化和气候变化的关系研究

从1970、1990、2000年和2010年4个时段的MSS、TM、ETM影像中提取了敦德冰川的边界,并结合距敦德冰川较近的托勒、大柴旦和德令哈3个气象站点的1957-2010年年降水量数据、年平均气温和夏季平均气温(6-8月)数据进行分析,对近40a来敦德冰川变化和气候变化的关系进行了研究.结果表明:近40a来的敦德冰川处在持续退缩状态;最近几十年敦德冰川退缩有相对加速之势;冰川在退缩过程中不断分解,部分分解后的小面积冰川融化消失.近半个世纪以来该区的气候增温趋势较明显,降水虽有少量增加,但是趋势却不明显.冰川变化与气候变化的关系表现为温度的升高是敦德冰川退缩的主要原因.     

遥感方法研究珠江口近二十多年来土地覆盖的变化

土地覆盖变化是全球变化研究的重点之一，尤其是河口地区，对环境变迁十分敏感。对珠江口东部地区1979年的Landsat MMS、1990年Landsat TM和2000年Landsat ETM影像的土地覆盖分类，并进行对比研究表明，此间，总体水域面积和绿地（包括森林和耕地）面积减少，建筑区和裸露地面积增加。但不同区域土地覆盖类型变化有明显的区别，西部主要是由于沉积作用和围海造地，造成水域面积减少，且20世纪90年代围海造地速率比80年代要大得多。东部海域沉积作用不是主要因素，局部海岸可能还存在侵蚀作用。交椅湾区水域面积变化不大，岸线位置也基本稳定，而且80年代的水域面积有所增多，是由于陆地人工水塘增多的结果。蛇口区主要是由于港口码头等建设，导致水域面积减少，码头向海域延伸的结果，90年代明显加大了码头建设的规模和速度。     

Detection of soil salinity changes and mapping land cover types based upon remotely sensed data

Soil salinity is a major environmental hazard. The global extent of primary and secondary salt affected soils is about 955 and 77 M?ha, respectively. Soil salinity tends to increase in spite of considerable effort dedicated to land reclamation. This requires careful monitoring of the soil salinity status. The objectives of this study were: (a) to evaluate the capability of thematic mapper (TM) and multispectral scanner (MSS) imagery for mapping land cover types, (b) to analyse the spectral features of sail crusts relative to bare soil and gravely soil surface conditions, and (c) to detect the soil salinity changes during the period 1975–2004 in the Ardakan area located in the central Iranian Deserts. The Landsat MSS and TM on two different dates of September 14, 1975 and September 11, 2004, respectively, were used. Due to great confusion between some classes, the TM 6 was included in the band combination. The result of the image classification based on the combination of TM bands 3, 4, 5, and 6 showed of the classification results. For multi-temporal analysis, both TM and MSS images were classified with the same method but with a different number of training classes. The TM-classified image was regrouped to make it comparable with MSS regrouped classified image. The comparison between the classified images showed about 39% of the total area had changed in 29 years. The result of this study revealed the possibility of detecting important soil salinity changes by using Landsat satellite data     

基于小波变换的遥感数据融合与边缘检测

介绍了小波图像的分解和重构方法以及小波融合过程。采用Symlet小波变换融合方法对西安地区鲸鱼沟水库的TM4、TM5子图进行单尺度二维离散小波变换融合，并进行水库的边缘检测。对图像通过TM4分解的低频图与TM5分解的高频图像融合再与TM4影像原图比较，融合图像提取细节效果明显优于TM4原图像。     

通过遥感对矿产资源开采中环境影响的研究--以阜新煤矿和排山楼金矿为例

阜新地区地处华北地台,富含煤和金矿床.呈东西向分布的太古宙和元古宙变质地层在华力西期、印支期和燕山期的变形和岩浆活动中发生隆起.金矿赋存于隆起的前寒武纪变质岩石中.成煤期为晚石炭-早二叠纪、早中侏罗纪、晚侏罗-早白垩纪.阜新煤矿和排山楼金矿是辽宁省的主要煤、金产地.
由于开采物中的有用物质只占很小的比例,因此提取有用物质的方式不可避免地要破坏当地的环境.矿山开采的每一步骤都对环境产生着负面影响.应用遥感资料进行矿山管理,是采用基于地表物体光谱反射的可视近红外(VNIR)遥感和短波红外(SWIR)遥感,以及基于物体热发光的热红外(TIR)遥感,利用不同的地表光谱反射,将相似的物体区分、分类、填图,并进行土地资源分析.野外工作包括在阜新煤矿和排山楼金矿确定岩石蚀变类型,采集标本,构造测量,对矿山环境进行数码拍照.陆地卫星MSS、TM和ETM+数据是分析研究的基础.应用ERDAS IMAGING软件处理卫星数据.并用ERDAS MapSheets和ViewFinder软件划图.应用各种图像处理技术进行图像增强和物体分辨.从卫星图像上直接测量排山楼金矿和阜新煤矿露天采场的多边形周长和面积.从卫星图像上可以看出,阜新煤矿从1980年到2000年环境的恶化.矿山开采产生的废矿堆不仅对矿区造成破坏,由于它们邻近市区,也通过视觉污染和噪音污染构成了潜在的环境污染源.开采活动对环境影响的另一个方面就是地面下沉,这是由地下开采造成的.它对地表的影响是明显的.本研究的重点是煤矿开采造成的地面下沉.与金矿脉的开采不同,煤矿的开采要移去数米厚的整个煤层.其结果不可避免地导致上覆地层的垮塌.排山楼金矿和阜新煤矿的另一个环境污染源来自矿石的处理(提纯和浓缩).金矿和煤矿都采用重力分离和浮选的方法.排山楼金矿目前采用先进的氰化-碳吸附选矿方法.作为补救措施,现在对用于浮选的化学剂的选择不仅要考虑其效益,而且要将其对环境的损害降到最低.尾矿处理也是影响环境的一个重要问题.阜新煤矿和排山楼金矿通常将尾矿倾倒地附近的人工坑内.这些区域虽然不至于对景观造成严重破坏,但很难在其表面恢复植被.而且,从该区域排出的水含有强酸和有毒的金属离子,一旦流入自然水系,将给水生生物造成大面积损害.堆放尾矿的区域一旦干燥,将产生另一个环境问题——粉尘污染.基于这些发现,提出如下建议：
（ 1）采矿过程中环境不断恶化的事实说明,两个矿山在控制露天开采方面仍有不足.虽然移动矿体上覆岩石或盖层是矿山开采的必要前提,但矿产资源的采掘必须对自然的保护给予更多的重视.应更加注重盖层的回填,植被、湿地、沼泽的恢复,控制溢出物,合理利用废物.
（2）地方政府应参与地区内矿产资源开发项目的立项、审批工作.政府在法律框架内干预、控制矿山开采行为中的环境和土地利用问题.     

基于时间序列的地表温度反演:以松江河地区为例

为研究同一地区不同时相的地表温度受植被和地表状况等因素影响后,其温度变化程度的差异,以Landsat 5 TM和Landsat 7 ETM+热红外数据为数据源,采用辐射传输方程法分别反演了松江河地区12个不同月份的地表真实温度,并分析出现稳态温度异常地段的影响因素,计算12个月的温度反演结果的均值和方差。结果表明:1平均值图像中的温度异常区域与绝大部分时相图像的温度异常区域十分相似,图像西北区域和中心区域出现较多温度异常。2方差图像中原系列图像中高温异常的区域,其方差也较大,即时间序列上温度波动较大;原系列图像中植被覆盖度较高的区域,其方差较小,即时间序列上温度变化较为稳定。     

Impact area determination of pyroclastic deposits in Lascar volcano, eruptive process in the year 1993

By means of multi-temporal analysis of satellite images and statistical algorithms, the amount of pyroclastic material deposited on Lascar volcano walls after the gravitational collapse of the eruptive column caused by the eruption that occurred on April the 19th and the 20th in 1993 was determined and quantified. For this analysis, scenes corresponding to Landsat 4 TM in 1989 and Landsat 7 ETM+ in 2001 were used. By careful selection methods such as combination of bands, unsupervised classification, and the Karhunen–Loève transform, detailed analysis of zones of change that correspond to pyroclastic deposits were made. This analysis was complemented with in situ data in order to correct and calibrate the satellite images to identify zones of 1993s eruption pyroclastic deposits. Using Kittler’s and other thresholding algorithms, a search was performed for a proper threshold to binarize the images to determine the surface area covered by the eruptive process. Matlab™ software was used both for general programming and for digital image processing.     

Multi-temporal landsat images based on eco-environmental change analysis in and around Chah Nimeh reservoir,Balochestan (Iran)

Chah Nimeh reservoirs have served as a water storage facility, especially during droughts over the last three decades. It is also an important wintering site for migratory birds. In this study, thematic mapper time-series data were derived from Landsat images for prolonged droughts that occurred in two satellite images (2002 and 2011). The data derived from these images were used for the detection of changes in land cover and water storage in the reservoirs. First, a vegetation cover map was produced using soil-adjusted vegetation index and field sampling. Subsequently, land use/cover maps were generated using supervised and hybrid image classification method. Using the spatial change detector (SCD v1.0) software extension, the layers were combined and the change map was generated. The overall accuracy of the produced thematic images was assessed in regards to quantity and allocation disagreements. A total of five classes were defined in this investigation: deep water, shallow water, vegetation, salt land and bare land. The results showed that during the period of study, water volume reduced and vegetation cover increased, especially around the reservoirs that are important as shelter for wintering migratory birds. Comparison of land use/cover maps showed the increase in total available surface of shallow water, which indicated an increase in the habitats for surface feeding and diving birds.     

Linkage of urban expansion and land surface temperature using geospatial techniques for Jaipur City,India

The aim of this study is to understand the land use change and urban expansion of Jaipur City of Rajasthan (India). Landsat 5 TM and Landsat 8 OLI satellite data of 4 years, i.e., 1993, 2000, 2010, and 2015 are used for land use and land surface temperature (LST) analysis. ERDAS Imagine and ArcGIS software are used to conduct the analysis. Urban settlement increased from 13.5 to 57.3% in the study period. Open land is mainly changed to urban areas. Urban settlement is also expanded to peri-urban area of Jaipur City. Jaipur City expanded along three directions i.e., north, west, and south and less development is found in the east direction. Based on radial analysis, it is observed there is not much development within the periphery of 2 km (close to city center) but maximum growth is observed within the distance from 4 to 6 km radius of city center. Expansion intensity was observed highest in the period 2015–2010 from 6 km onwards and reached to a maximum value close to 17 km²/year. In LST analysis, there is less change in extreme temperature, but more areal increase in average temperature range (30–35 °C). Urbanization is the main driving process of land cover changes and consequently changes in LST.     

Utilizing image processing techniques in lithologic discrimination of Buwatah area, Western Arabian Shield

The main task of this article is the evaluation of the IHS color transformation fusion, color composite ratios, and principal component analysis techniques for lithologic discrimination of the basement rocks exposed at Buwatah area, Western Arabian Shield, Saudi Arabia. Landsat ETM+ images were prepared and used to perform this task using PCI Geomatica software. IHS fusion technique was conducted through four main processing steps: (1) registration of the multispectral image (7, 4, and 2 in RGB) to the panchromatic image and then resample it to the same spatial resolution as that of the panchromatic image; (2) transformation of the three multispectral bands from RGB to IHS space; (3) substitution of the intensity value from the high spatial resolution panchromatic band; and finally (4) back transformation to RGB. The band ratios 5/7, 3/1, and 4/3 displayed in RGB, respectively, were used to produce the color composite ratio image. The first principal component (PC1), the second principal component (PC2), and the third principal component (PC3), displayed in RGB, respectively, were used to construct the color composite principal component image. The resultant images successfully discriminated the exposed rock units in the study area and a lithologic map has been constructed that is subjected to precise field verification. The stratigraphy of the area under consideration starts with metavolcanics and associated volcaniclastics as an oldest rock unit, followed by granodiorite–diorite, pink granite, biotite granite, acidic and basic dykes, and Cenozoic volcanics. A new rock unit (biotite granite) has been introduced that was not represented in previous mapping of the considered sector. The biotite granite is verified by field and petrographical studies.     

近30年来西藏那曲湿地变化及驱动力探讨

以RS/GIS为主要手段, 以基于60年代末航片绘制的那曲县1: 10万地形图、1990年TM遥感数据、2000年ETM遥感数据和1∶25万DEM数据为主要数据源, 结合那曲县温度、降水等资料, 对那曲县湿地分布、面积变迁和驱动力进行分析, 结果表明: 那曲县湿地变迁总体趋势自20世纪70年代以来呈萎缩趋势。空间差异表现为: 那曲县西部小型断陷湖盆谷地区域的湿地面积自70年代以来一直呈现萎缩趋势, 东部、南部高山宽谷地区、河源区湿地自经历70～90年代扩张后, 在90年代面积转为萎缩。气候波动和频繁的人类活动是湿地变迁的驱动力, 湿地的地质、水文等背景因素的不同可能是变迁差异的重要原因。     

CPF变化对Landsat TM/ETM+辐射校正结果的影响

随着时间的推移,卫星传感器的老化会使得原有的辐射定标参数文件(CPF)失效。最典型的当属Landsat-5卫星,该卫星自1984年发射以来,已经进行了多次CPF修正;而Landsat-7卫星的CPF也经过了数次修改,以保证辐射校正结果的准确性。以Landsat TM/ETM+遥感影像为例,分别以2003、2009年的CPF对它们进行辐射校正,并对结果进行对比。结果表明,除ETM+的绿光波段外,TM、ETM+影像基于2009年CPF计算的各波段均值都要小于2003年。而这一变化也使得由此计算的指数产生差异：归一化植被指数(NDVI)间的差异可达0.48%,建筑用地指数(IBI)间的差异可达5.94%。     

Assessment of the mutual impact between climate and vegetation cover using NOAA-AVHRR and Landsat data in Egypt

The objective of the current study is to use satellite data to assess the mutual influence between vegetation and climate. The Ismailia Governorate was selected as a case study to investigate the impact of vegetation cover expansion on both land surface and air temperature from 1983 to 2010 and vice versa. This observation site was carefully selected as a clear example of the high rate of the reclamation and vegetation expansion process in Egypt. Land surface temperature (LST) was estimated through the Advanced Very High Resolution Radiometer (a space-borne sensor embarked on the National Oceanic and Atmospheric Administration) data while air temperature (T _air) was collected from ground meteorological stations in the study area. Irrigated agriculture is the largest consumer of freshwater resources. However, consistent information on irrigation water use is still lacking. Relative humidity, wind speed, solar radiation, and T _air data were inserted in the Penman–Monteith equation to calculate potential evapotranspiration (ET_o), while both LST and T _air were used to observe the relative water status of the study area as a result of the water deficit index (WDI). Then, both WDI and ET_o were used to calculate actual evepotranspiration (ET_C.). The results showed that LST decreased by about 2.3 °C while T _air decreased by about 1.6 °C during the study period. The results showed also that the vegetation cover expanded from 25,529.85 ha in 1985 to 63,140.49 ha in 2009 with about 147 % increase. This decrease in LST and air temperature was according to the expansion of the cultivated land that was proved through the processing of three Landsat TM and Landsat ETM+ imageries acquired in June 19, 1985, June 7, 1998, and June 29, 2009. The vegetation water consumption was affected by the decreasing surface and air temperature. The results showed that the water deficit index decreased by about 0.35, and actual evapotranspiration increased by about 2.5 mm during the study period.     

Landslide susceptibility assessment using object mapping units,decision tree,and support vector machine models in the Three Gorges of China

Due to the particular geographical location and complex geological conditions, the Three Gorges of China suffer from many landslide hazards that often result in tragic loss of life and economic devastation. To reduce the casualty and damages, an effective and accurate method of assessing landslide susceptibility is necessary. Object-based data mining methods were applied to a case study of landslide susceptibility assessment on the Guojiaba Town of the Three Gorges. The study area was partitioned into object mapping units derived from 30 m resolution Landsat TM images using multi-resolution segmentation algorithm based on the landslide factors of engineering rock group, homogeneity, and reservoir water level. Landslide locations were determined by interpretation of Landsat TM images and extensive field surveys. Eleven primary landslide-related factors were extracted from the topographic and geologic maps, and satellite images. Those factors were selected as independent variables using significance testing and correlation coefficient analysis, including slope, profile curvature, engineering rock group, slope structure, distance from faults, land cover, tasseled cap transformation wetness index, reservoir water level, homogeneity, and first and second principal components of the images. Decision tree and support vector machine (SVM) models with the optimal parameters were trained and then used to map landslide susceptibility, respectively. The analytical results were validated by comparing them with known landslides using the success rate and prediction rate curves and classification accuracy. The object-based SVM model has the highest correct rate of 89.36 % and a kappa coefficient of 0.8286 and outperforms the pixel-based SVM, object-based C5.0, and pixel-based SVM models.     

Research on the Application of the Light-Energy Spectrum Fusion Technique to Land and Resources Survey

This paper introduces how to use remote sensing images including Landsat (MSS and TM) andairborne radioactivity images to identify the type of rocks in the areas covered by vegetation. The relationship between light spectrum (Landsat MSS and TM) and energy spectrum (U, Th and K) is discussed on the basis of correlation analysis, and it is proven that there are correlations between the Landsat MSS or TM data and the U, Th and K. data. By using the fusion technique, new images were generated, which contain both the light spectrum and the energy spectrum information.Taking the Lucong basin as the study area, the present paper demonstrates the successful identification of various types of rocks using the fusion technique. Different types of rocks are represented by different colours on the new light-energy spectrum images, so that volcanic rocks of the Jurassic and Cretaceous periods can be discriminated. Another example, in the Lingquan basin in Northeast China, not only the different types of rocks are su