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The paper introduces the application of hydraulic model in environmental problems, discusses several examples using hydraulic model in environmental problems and several important factors in the process of the use of hydraulic model to study the water environment pollution simulation, which involves abnormal model, the transverse diffusion coefficient, pollutant simulation and so on. The applicable conditions, constraints and their possible solutions of this technology are also discussed.

This paper is to propose a method of ecological carbon sink regionalization in the view of GHG (greenhouse gas) emission reduction, which could provide scientific theory basis for development and utilization of urban land resources, ecological environment construction, biodiversity conservation, the industry layout and formulation of the regional sustainable development strategy. Based on the existing researches foundation, this study takes Shenzhen as a typical case to put forward a method for carbon sink regionalization of urban land use with further quantitative evaluation of ecosystem carbon storage (density), carbon sources/sinks function and carbon sink potential of Shenzhen city. The results show that: Shenzhen ecological carbon sink is regionalized into six categories 55 regions, including 15 intensive carbon sink regions, 17 medium carbon sink regions, 10 weak carbon sink regions, 4 carbon neutral regions, 5 medium carbon source regions and 4 intensive carbon source regions.

The carbon emission caused by land use change is a human carbon source only second to fossil fuel combustion, the urbanization process in China is extremely intensified, which carbon emissions effect caused by land use change becomes a key factor to influence China's target of carbon emission reduction. Taken Shenzhen city as a typical case, this study utilizes unit root and co-integration test method to research existence of carbon emissions EKC (Environmental Kuznets Curve) in Shenzhen on the basis of the carbon emissions EKC theory and land-use carbon emissions data of 1979-2010 years, in combination with the existing research foundation. The result proves that, the carbon emission EKC per capita exists in Shenzhen, and the inflection point time of carbon emissions per capita is also calculated for Shenzhen city, which provides new research ideas and scientific guidance for urban carbon emission reduction in China.

IBIS (Integrated Biosphere Simulator) model is an ecosystem process model, which represents the research direction of a global carbon cycle simulation. Based on the existing research achievements, the regional ecological carbon sink potential is simulated from point to surface with a long time serie of meteorological data (1954-2010), data on different ecosystem vegetation types, soil texture data, terrain data and remote sensing data. The results are listed as follows: there is no significant variation of potential carbon sink of Shenzhen vegetation over the past 30 years, carbon sequestration caapcity ranges within 43.52-55.82×104Mg C/a, and the potential carbon sink intensity value within 0-624 C/m2/a. Precipitation is a main factor which influnces the ecosystem carbon sink intensity in Shenzhen City. The carbon sink intensity of ecosystem is increased with more annual precipitation.

This study combines the sampling technique, geographic information system and remote sensing technique to conduct a sampling survey on forest cover area of Jinggangshan National Nature Reserve in China on the basis of TM remote sensing image. The spatial simple random sampling, spatial stratified sampling and sandwich sampling model are respectively utilized to establish the sampling design. For the spatial simple random sampling model, the spatial autocorrelation analysis method is adopted to determine the spatial autocorrelation coefficient through calculating Moran's I index, while in the spatial stratified sampling and sandwich sampling model, the yearly maximum NDVI (Normalized Difference Vegetation Index) is utilized to conduct the spatial stratification. Through comparison of the sampling accuracy of three sampling models, a higher precision and more reasonable sampling method and sampling model is provided for remote sensing monitoring of forest cover area. The study results show that: sandwich sampling model is featured as the highest sampling accuracy, followed by the spatial stratified sampling and simple random sampling. Under the requirement of same precision, sandwich spatial sampling model can reduce quantity of the sampling points, and create all kinds of report units according to demands of different spatial area, so it is featured as the better suitability.

The effects of terrestrial carbon cycle caused by Land use change on are obvious. Urbanization is an important reason of land use change. Based on the soil and plant data that field sampled, five remote sensing data of 1979, 1989, 1995, 2000 and 2003, the effects on ecosystem organic carbon pool from1979 to 2003 caused by land use change in Shenzhen city are analyzed. The land use changes are mainly occurred between the following 8 land types, farmland, wood land, grass land and construction land. The results show that form 1979 to 2003 carbon emissions caused by land use change in Shenzhen City totally reduced by 337.24 × 104Mg C (1Mg C = 1 × 106g C). The average annual carbon emissions arrive up to 24.09 × 104Mg C. Among them, the emissions caused by the reductions of farmland and forest area are respectively 252.26 × 104Mg C and 111.73 × 104Mg C. The organic carbon increment caused by garden land increase is 47.37 × 104Mg C. The results show that Urbanization process totally is a carbon sink process. The study is valuable for assessing the relations between carbon effects and land development and ecological restoration planning in the process of rapid urbanization.

Land-use and land-cover change (LUCC) is an important factor of global change. In this study, the LUCC of Liaoning Coastal Economic Zone, the typical area of urbanization in China, was simulated by applying CLUE-S model under the historical trend scenario and policy scenario two scenarios. Transfer matrix and landscape index were also applied to analyze the change of landscape pattern. The results show that, from 1988 to 2007, the area of construction land was considerably increased. However, the area of forest, water and farmland were greatly decreased. The results were mainly caused by the rapid growth of economic, population and accelerated urbanization. These changes have caused landscape fragmentation in this study area. In general, the trends of landscape changes under two scenarios were unsustainable in this area.