Advanced Materials Research Vols. 518-523

Abstract: In this paper, serial data of daily Normalized Difference Vegetation Index (NDVI) cloudless day from March to November 2011 in Chongqing was used, and Time-series NDVI such as a period of ten days’ (or monthly/yearly) maximum NDVI under cloudless day was obtained. The serial NDVI with different period of time were divided into 6 characteristic districts according to height. The results of the analysis showed as following: growth of vegetations had obvious seasonal variation that the number of NDVI was gradual increase during March to April, and was bigger during May to September, gradually decreased after October. From mid-August to mid-September, and the NDVI of the Middle and West of Chongqing was less than normal owing durative drought. The NDVI was increased with increasing of highness and NDVI increaseed rapidly below 1500m while increased slowly above 1500m that showed better was the ecological environment, higher was the altitude.

Abstract: Sichuan is one of the provinces in China with worst natural disasters, which with variety, wide range, and high frequency characteristics. In this paper against the basic geographic information system data and a variety of geographic applications, we design a provincial disaster relief and emergency command GIS platform, and build integration geographic information online service system based on multi-node. This design of GIS emergency command system achieved vertical and horizontal connectivity and effective integration of geographic information resources for city, provincial, and state. It with comprehensive service capabilities of geographic information service and multi-level interact. It also provides one-stop geographic information service. It offers online geographic information services for the government's macroeconomic policy, emergency management, and social welfare services, and enhances geographic information and public service capacity and level under conditions of informatization.

Abstract: Based on the fundamental meaning of Geographic Information System (GIS), the important features of GE Smallworld and the fundamental features of Forest Resources, we discuss the current application in forest resources information management, forest insect pest and disease control, the integration between GPS (global positioning system) and RS (remote sensing), resource management in nature reserve. At the same time the further development of GE Smallworld in forest resources management has been analyzed.

Abstract: Take Songzao mining area in Chongqing for example, the damage situation of coal mining subsidence land in mountainous area was studied, optimum evaluation indexes for damage situation of land was selected by discussing existing evaluation indexes, and the contestant standard formed by using Delphi method, and grade of damage situation of coal mining subsidence land was confirmed by overlying analytical method of GIS raster data. The results showed that the degree of land destruction most belong to slight and middle damage, the relatively serious damage forms were collapse pit and collapse crack, and the degree of land destruction tends to weaken gradually from mining center to edge. There was a positive correlation between the degree of land destruction and mining degree.

Abstract: The aim of this study is to assess the capability of estimating Leaf Area Index (LAI) from high spatial resolution multi-angular Vis-NIR remote sensing data of WiDAS (Wide-Angle Infrared Dual-mode Line/Area Array Scanner) imaging system by inverting the coupled radiative transfer models PROSPECT-SAILH. Based on simulations from SAILH canopy reflectance model and PROSPECT leaf optical properties model, a Look-up Table (LUT) which describes the relationship between multi-angular canopy reflectance and LAI has been produced. Then the LAI can be retrieved from LUT by directly matching canopy reflectance of six view directions and four spectral bands with LAI. The inversion results are validated by field data, and by comparing the retrieval results of single-angular remote sensing data with multi-angular remote sensing data, we can found that the view angle takes the obvious impact on the LAI retrieval of single-angular data and that high accurate LAI can be obtained from the high resolution multi-angular remote sensing technology.

Abstract: This paper illustrates almost twenty years (1986～2007) of Land use/land cover change (LULCC) in Qingpu-one district of Shanghai. Qingpu District is an area of Upper Huangpu Catchment for fresh water supply with considerable ecological value, but it is also experiencing urban sprawl from development. To reveal the trends underlie LULCC, we propose a novel procedure to quantify different land use/land covers and implement it in the case study. In this procedure, we first collect historical remote-sensing data and co-registered or corrected them to the same spatial resolution and radioactive level. Based upon preliminary interpretation or investigation, land use/land cover types in study area can be included in 5 categories, i.e. Water, Agricultural Land, Urban or Built-up Land, Forest Land, and Barren Land or others. Moreover, data is clipped via boundary of study area for reducing computation load, followed by FPCR-ISODATA classification to divide the data into k groups (k>the number of land types). After postprocessing, e.g., merge the same connoted subgroups and correct misclassified units accompany with validation and verification, the detailed land use/land cover results can be achieved accurately. The quantitative and regression analysis indicate that during the past twenty years the area of agricultural land of Qingpu decreased coupled with urban or built-up area increased linearly. The water area had the minimum change during the decades. Forests had the smallest average proportion (9.6%) of the total area. It occupied so small proportion of land that we can only find points of it in the maps. Barren land can be an indicator for monitoring uncompleted redevelopment or transition of land.

Abstract: Soil salinization is one of the most common land degradation progresses in Yellow River Delta (YRD) of China. Remote sensing is widely viewed as a time- and cost-efficient way for detection of soil salinity. In this study, we collected 55 soil samples and corresponding field spectra from the Yellow River Delta of China to investigate the level of soil salinity in relation to soil spectra. A partial least square regression (PLSR) model was created between field measured spectra (The spectra have been resampled to Advanced Land Imaging (ALI) spectral resolution) and soil salinity. Significant correlation was observed between predicted values and measured values with determination coefficient (R²) of 0.837. The PLSR mode was then applied to ALI reflectance image on a pixel-to-pixel basis. The result indicated that it is an efficient method that produces, fast, wide-coverage, and reliable distribution map of soil salinity using field-derived spectra and ALI multispectral imagery with PLSR method.

Abstract: This article takes typical Valley City in Northwest as the research object and takes Yanan as an example. Firstly, the urban space is analyzed and divided during the thinking of multi-scale science, and then the image of Yanan in 2011is interpreted and the internal space and external morphology can be quantitatively analyzed at multiple spatial scales using the method of GIS. The analysis shows that different feature of land use types in different scale space and terrain on different land use types distribution impact. The research findings are meaningful for the spatial expansion, update, spatial layout of the valley city in Northwest and contribute to the healthy development of the city in northwest area.

Abstract: For the characteristics of the marine environment data with multiple-formats, heterogeneous, multi-dimensional and dynamic in structure and time, this paper studies the three-dimensional visualization method of the NetCDF-based marine environment data. On the basis of comprehensive analysis the NetCDF data model in principle, data organization, scheduling methods and so on, the present study proposes NetCDF to store these data, and designs a 3D dynamic rendering model for typical marine environment data based on virtual earth, implements the dynamic representation and spatial-temporal analysis, which includes marine feature field visualization, the attributes information query and the process characteristics analysis. The practical application shows that the method of this paper can represent massive marine environment data efficiently and vividly, it provides a powerful visualization auxiliary tool for the representation of the complex ocean phenomena, spatial-temporal analysis and trend prediction.

Abstract: In order to make a quantitative analysis on the change of the ecological environment, special land cover classification was established to reveal the influence of human activities in ecological environment resource utilization in Three Gorges Reservoir Area and their evolution process. Land cover information were obtained from image interpretation and then made an analysis by using transition matrix. Finally, the main way and the rule of land cover changes in Hubei, Three Gorges Reservoir Area in 2003 and 2009 were found out.