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The present study attempted to evaluate the influence of human activity on major elements (Na2O, MgO, Al2O3, SiO2, K2O, CaO, Fe2O3), and to find a method to explore correlations between major elements and human disturbances, according to geospatial theories and methods. The study results indicate that landscapes influence major elements in diverse ways: Al2O3 is closely related to road and mine landscapes; strong relationships exist between MgO, Fe2O3, CaO, and SiO2 and roads; Na2O, SiO2, and Fe2O3 are unrelated to city landscapes; and Na2O is unrelated to road and mine landscapes.

Soil chemical elements are important parameters for soil origin diagnosis, and are sensitive indicators of human disturbance process. The present study attempts to evaluate the influence from human activities on halogen elements (fluoride and iodine). This study also attempts to seek a route to explore the spatial relationships between human disturbances and halogen elements according to geospatial theories and methods. Moreover, the spatial correlations between element anomalies and human disturbed landscapes are calculated to explore the influence from human activities on halogen elements, thereby determining the specific response mechanism. The study results indicate that landscapes influence halogen elements in diverse ways and that element iodine is closely related with road and mine landscapes. Furthermore, strong relationships exist between fluoride and road landscapes, which suggest that this element is affected by road landscapes significantly. Fluoride and iodine are unrelated with city landscapes, and fluoride is unrelated with mine landscapes. These provide a reference for the research on the interaction mechanism between halogen and environment. Therefore, it can be concluded that a response mechanism exploration of soil element aggregation and human disturbance is practicable according to geospatial theories and methods, which provides a new idea for studying the soil element migration.

A river watershed is a complicated ecosystem, and its spatial structure and temporal dynamics are driven by various natural factors such as soil properties and topographic features, human activities, and their interactions. Thus, characterizing the river watershed ecosystem and monitoring its dynamics is very challenging. In this study, we explored the characteristics of the ecosystem and environment of Yalong River watershed in Ganzi Tibetan Autonomous Prefecture, Sichuan Province of China by analyzing and modeling the relationships among economic indices, heavy metal elements and landscape metrics. Landsat 8 data were used to generate a land cover classification map and to derive landscape pattern indices. Governmental finance statistics yearbook data were referred to provide economic indices. Moreover, a total of 9 water samples were collected from the upstream to the downstream to obtain the values of heavy metal concentrations in the water body. Then, both correlation and regression analyses were applied to analyze and model the relationships among these indices. The results of this study showed that 1) The ecological status and process of this river watershed could be explained by analyzing the relationships among the economic indices, heavy metal elements and landscape pattern indices selected based on correlation analysis; 2) Compared with the economic indices, the accumulated economic indices were more significantly correlated with most of the heavy metal elements and should be applied for the integrated assessment of the watershed ecological environment; 3) Landscape pattern indices SHDI and IJI had strong correlations with the important economic indices Population and Population Density and could be used for the integrated assessment of the watershed characteristics; 4) Compared with land cover area, land cover area ratios were more sensitive to the variation of the economic indices. The dominated land cover types Forest and Grassland had strong relationships with the economic indices; and 5) Cu and Zn had significant correlations with the landscape pattern indices. This study implied that analyzing and modeling the relationships among the economic indices, heavy metal elements and landscape pattern indices can provide a powerful tool for characterizing the ecosystem of the river watershed and useful guidelines for the watershed management and sustainable development.

In order to solve the problem of high cost and low efficiency by using the traditional soil geochemical survey methods, this paper studied the simple detection method of soil heavy metal content with visible and near-infrared reflectance spectroscopy. The study collected visible and near-infrared reflectance spectroscopy of soil samples in Xifanping mining area; then treated the reflectance spectroscopy with six mathematic changes such as differentials and continuum removal in advance; the next step was to select characteristic wavelengths that were sensitive to soil copper content by using stepwise regression method and Pearson correlation coefficient as set of comprehensive characteristic variables; finally, utilized different methods and parameters of characteristic variable selection to build the soil total copper content models and tested them. Results showed that: to extract the information of copper content in soil, the performance of different spectral transform methods varied, and each spectrum transform method corresponded to its certain sensitive spectral ranges; the inversion models based on the integrated spectrum transform information were better than that based on only one kind of spectrum transform information; as for establishing the prediction model of soil copper content by using the integrated spectrum transform information, backward elimination was better than forward selection and stepwise selection, and when the Removal is 0.20, the optimum model was obtained, its coefficients of determination(R(2))and determination coefficients of prediction(R(2)(pre))reached 0.851 and 0.830, root mean square error of calibration(RMSEC)and root mean square error of prediction(RMSEP)were 0.349 and 0.468 mg·kg(-1). The model has a good precision, and it provides a train of thought for the detection of other soil heavy metal elements with visible and near-infrared reflectance spectroscopy.

The development and formation of chemical elements in soil are affected not only by parent material, climate, biology and topology factors, but also by human activities. The pollution sources of heavy metals in the environment are mainly derived from anthropogenic sources, and heavy metal elements in soil have been considered to be powerful tracers for monitoring the impacts of human activities. The present study attempts to analyze whether and how a connection can be made between macroscopical control and microcosmic analysis, to estimate the impacts of human activities on heavy metals in soil, and to determine a way to describe the spatial relationship between heavy metals in soil and human activities, by means of landscape geochemical theories and methods. In addition, the disturbances of human activities on Zn, Cr, Cu, Pb, Hg, Cd, Ni and Ag are explored through the analysis of the spatial relationship between human disturbed landscapes and element anomalies, thereby determining the diversified rules of the effects. The study results show that the rules of different landscapes influencing heavy metal elements are diversified, and that the Zn, Ni, Pb, Hg and Ag elements are closely related with city landscapes, but Cu and Cd are not significantly affected by city landscapes; furthermore, the elements Ni, Pb, Hg, Ag and Cd are shown to be closely related with river landscapes, while evidently Zn is not affected by river landscapes; the relationships between mine landscapes and the elements Cr, Cu, Pb, Ni and Hg are apparent, among which Zn is not included; the relationships between the elements Zn, Cr, Cu, Pb, Hg, Cd, Ni and Ag and road landscapes are quite close, which shows that road landscapes have significant effects on these elements. Therefore, the conclusion is drawn that the response mechanism analysis of-human disturbance and soil chemical element aggregation is feasible, based on the landscape geochemical theories and methods. The results of the study provide the possibility for applying spatial information techniques, such as remote sensing and geographic information systems, to study chemical elements in soil, thereby realizing the effective combination of macroscopic spatial information and microscopic mechanism of soil element migration research. (C) 2014 Elsevier B.V. All rights reserved.

Most of Tianshan highway is located in Xinjiang where is the high and cold mountain area. Drifting snow and other disaster continue to occur, seriously affecting road traffic. Conventional monitoring is difficult to meet the emergency needs due to the influence of climate, topography, etc. The article selected MODIS data to inverse snow depth and temporal-spatial distribution in Dushanzi-Kuqa region of Tianshan Highway in recent years. Analysis revealed that the snowfall mainly was concentrated from the end of October to the beginning of April in the next year. The snow area is the least in summer of July, but the largest in winter, accounting for about 35.7% of the entire study area, the snow depth in most areas at 12 to 15 cm, the maximum snow cover depth is about 23 cm in the Dushanzi region of Wusu County. The results of study has a very important theoretical and practical significance to monitoring and control of diseases.

Land surface temperature (LST) of the Nanchong City in China was retrieved using Landsat TM/ETM+ images, which obtained on September 15, 1988, July 22, 2000, and September 20, 2007 respectively, and then be classified by Mean-standard Deviation method. The spatio-temporal evolution of UHI was analyzed including UHI distribution variation and transformation. Research result are the following: (1) The UHI area in the Nanchong city was continually increasing from 1988 to 2007, and the rate in the later period (from 2000 to 2007) was 1.8 times that in the previous period (from 1988 to 2000). The UHI expansion was synchronous with built-up area, and the expansion form was extending along and outwards the Jialing River. (2) The UHI-in area was far greater than the UHI-out area from 1988 to 2007. In the previous period, the UHI-into rate was 4.0 times that of UHI-out, and in the later period, the UHI-into rate was 2.2 times the UHI-out rate. Comparison of the previous and later period, the UHI-into rate or UHI-out rate was increasing, but the increased scope of UHI-into rate was more 22.42 hm2/a than UHI-out rate. In short, the UHI in the Nanchong City was continuously strengthening from 1988 to 2007, and the rate in the latter period was higher than that in the previous period.

Derong County is located in Ganzi Tibetan Autonomous Prefecture in southern part of Sichuan Province, in the upper of the Jinsha River, where there is a subtropical plateau monsoon climate, abundant sunshine, and large amount of evaporation, so it is a typical dry-hot valleys region. Derong County is the area of more ups and downs in the terrain, deep valleys, steep mountains, complex geological conditions, intense tectonic activity, various climate types, and has obvious vertical zone effect by temperature, serious physical weathering of rock, and landslide, debris flow, collapse and other geohazards are easily induced under the influence of rainfall and human engineering activities. These geohazards have brought serious harm to the people's lives and property, and have a great impact on the socio-economic development. Through the analysis of geohazards in the study area to investigate its distribution and development trends, this paper provide a basis for geohazard prevention and economic development.

In this paper, taking the underground cavities of Nuozadu Hydro-electrical Power Station located in Lancang River as an example, three-dimensional finite element numerical modeling technique is used to analyze systematically the distribution features secondary stress field, displacement field and failure zone in the surrounding rock mass of the underground cavities after the excavation when the surrounding rock mass quality rank change fromⅡ to IV. The influences of rock quality on excavation effects are discussed in detail.

On account of the special landform, geology and rainfall condition, Tianshan Mountain influences the traffic normally. It often comes under bedload, coast, dilapidation at one time. This threatens the stability of the road and the security of denizen along the line. It is especially importment of the Geological disaster decision-making sustain Geography Information System in Tianshan Mountain bring to bear the advanced technology, which sustains in the build and manage of Tianshan Mountain. After analyzing the on the theory of geological hazard about Tianshan road in detail, collected the datum of basic geography and geology along the lines of road in the past, and also contrasted the locale results and remote sensing images, building and consummating both the Geography database and the geological hazard database based the platform of ArcGIS after according synthesizing, coordinating, choosing, concluding and changing by the rules of database. Asked on the ArcEngine platform, developing a set of collections foundations data gathering, the memory, the management, the retrieval, the graphic editor, the space model analysis, the line region stability assessment, the highway alignment route selection as well as the three dimensional route flight achievement graph production and the output is a body “The Tianshan highway geohazard stability appraisal and the route selection optimization analysis system”.

Lakes are very important in freshwater supply. At present, most of the lakes in the world are suffering from eutrophication with industrialization, economic growth, and human activities. Frequent monitoring and integrated management are necessary for lakes. Chlorophyll-a (chl-a) is the important indicator of phytoplankton and water quality. However, conventional methods for monitoring chl-a in lakes will waste more manpower and material resources and can't provide water quality information of the whole lake. Remote sensing technique is suitable to obtain spatial and temporal information quickly and frequently, and it will be widely applied in water quality monitoring for lakes in future because of its advantage of efficiency and long-term dynamic monitoring. The images covering the Tai Lake for the study are TM of 1991-07-23 and ETM+ of 2001-07-26.The chlorophyll-a concentration has been extracted from the two-period images of the Tai Lake based on a statistical model and the spatial distribution maps with three levels based on chlorophyll-a concentration have been made to display the distribution regularity of concentration.

Base on synthetically analysis of Mountains terrain characteristics, this paper uses analytic hierarchy process (AHP) to study classification of Mountains terrain characteristics of the Sichuan Mountains which lies in China's Sichuan Province, according to applying characteristics of AHP. This paper builds the recursion stage structure model using to the mode of highestlevel, middle-level and lowest-level. In the light of the five extracted classification factor and combining the assessed index of Mountains terrain characteristics, an index system should divide into A which notes target-layer and B which notes index-layer (factor-layer). According to the index system, the weights of five extracted classification factors are calculated by using established judgment matrixes. Sichuan Mountains terrain Layer can be extracted in ArcGIS and the result of characteristic is analyzed. Finally, The result of seven characteristics of classification is obtained, which supplies the new classification evaluate means for mountainous region synthesized research and application.

Spatial heterogeneity of the vegetative will appear new change and new feature when we observe it with different scale. In order to understand the vegetative pattern and dynamic state well and profoundly, we must take into account the characteristics which vary with the different scales. Fractal geometry is a feasible tool to solve the problem. The spatial distribution of the vegetation is a typical fractal object and show details in different scales. The fractal dimension always embodies self-similar characteristics which mean they don't change with the scales. Consequently, comparing the spatial pattern and the fractal dimension between different scales will make us understand the spatial pattern roundly. Based on regionalized variable theories, geo-statistics is one kind of spatial statistical theory used to explore the correlativity and dependence between spatial variables. The first character of this method is its emphasis on the importance of spatial dependence of variables. In practical research, semi-variance values of ecological factors or other indices can be calculated from the semi-variance formulate according to the theory, and then, semi-variogram can be drawn, distribution character of the vegetation (such as clumped or uniform pattern) can be found from the graph. Mathematical models simulation should be used in quantification of this character. In this paper, we take the vegetation of XINJIANG province for example. The fractal dimension was calculated by the double-logarithm semi-variogram. The lower the value of the fractal dimension is, the higher heterogeneity the distribution of vegetation has.

Analyzing the on the theory of geological disease about Tianshan road in detail, collected the datum of basic geography and geology along the lines of road in the past, and also combined the technology of database and remote sensing images manipulation, according synthesizing, coordinating, choosing, concluding and changing by the rules of database. It offered the favorable resolving for region stability assessment, the highway alignment route selection and 3D Visualization analysis, integrating GIS spatial analyzing technology to the Tianshan highway geo-disease appraisal and decision-making. The system developed a set of GIS manipulation flat of collecting foundations data gathering, the memory, the management, the searches, the graphic editor, the space model analysis and so on. Adopting integration exploiting technology of ArcEngine and Visual C#. Building multiformity information database the Geography database and the geological hazard database based the platform of ArcGIS. Managing space data and attribute data subsequently using ArcSDE. It is reliable scheme to engineering geo-disease appraisal and decision-making.