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Developing land use scenario dynamics model by the integration of system dynamics model and cellular automata model

Science China Earth Sciences 2005年第11期48卷 1979-1989页

作者： HE Chunyang, SHI Peijun, CHEN Jin, Li Xiaobing, PAN Yaozhong, LI Jing, LI Yuechen & LI Jinggang Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education of China, Beijing Normal University College of Resources Science & Technology, Beijing Normal University, Beijing 100875, China Key Laboratory of Environmental Change and Natural Disaster Ministry of Education of China Beijing Normal University China College of Resources Science & Technology Beijing Normal University Beijing China

Modeling land use scenario changes and its potential impacts on the structure and function of the ecosystem in the typical regions are helpful to understanding the interactive mechanism between land use system and ecological system. A Land use Scenario Dynamics (LUSD) model by the integration of System Dynamics (SD) model and Cellular Automata (CA) model is developed with land use scenario changes in northern China in the next 20 years simulated in this paper. The basic idea of LUSD model is to simulate the land use scenario de-mands by using SD model at first, then allocate the land use scenario patterns at the local scale with the considerations of land use suitability, inheritance ability and neighborhood effect by using CA model to satisfy the balance between land use scenario demands and supply. The application of LUSD model in northern China suggests that the model has the ability to reflect the complex behavior of land use system at different scales to some extent and is a useful tool for assessing the potential impacts of land use system on ecological system. In addition, the simulated results also indicate that obvious land use changes will take place in the farming-pastoral zone of northern China in the next 20 years with cultivated land and urban land being the most active land use types.

关键词： system dynamics, cellular automata, scenario, land use, model

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The consequences of uncertainties in land use, climate and vegetation responses on the terrestrial carbon

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Science China(Life Sciences) 2002年第Z1期45卷 126-141页

作者： Rik Leemans Bas Eickhout Bart Strengers Lex Bouwman Michiel Schaeffer Institute of Public Health and the Environment P. O. Box 1 3720 BA Bilthoven The Netherlands

The IPCC SRES narratives were implemented in IMAGE 2.2 to evaluate thefuture condition of the climate system (including the biosphere). A series of scenario experiments was used to assess possible ranges in emissions and concentrations of greenhouse gases, climate change and impacts. These experiments focussed on the role of the terrestrial carbon cycle. The experiments show that the SRES narratives dominate human emissions and not natural processes. In contrary, atmospheric CO2 concentration strongly differs between the experiments. Atmospheric CO2 concentrations range for A1B from 714 to 1009 ppmv CO2 in 2100. The spread of this range is comparable with the full SRES range as implemented in IMAGE 2.2 (515-895 μmol/mol CO2). The most important negative and positive feedback processes in IMAGE 2.2 on the build-up of CO2 concentrations are CO2 fertilisation and soil respiration respectively. Indirect effects of these processes furtherchange land-use patterns, deforestation rates and alter the natural C fluxes. The cumulative effects of these changes have a pronounced influence on the final CO2 concentrations. Our scenario experiments highlight the importance of a proper parameterisation of feedback processes, C-cycle and land use in determining the future states of the climate system.

关键词： carbon cycle, feedback processes, integrated assessment modeling, land use, SRES scenarios.

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Land use effects on terrestrial carbon sources and sinks

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Science China(Life Sciences) 2002年第Z1期45卷 1-9页

作者： Josep G. Canadell Global Carbon Project GCTE CSIRO Land and Water PO Box 1666 Australia

Current and past land use practices are critical in determining the distribution and size of global terrestrial carbon (C) sources and sinks. Althoughfossil fuel emissions dominate the anthropogenic perturbation of the global C cycle, land use still drives the largest portion of anthropogenic emissions in a number of tropical regions of Asia. The size of the emission flux owing to land use change is still the biggest uncertainty in the global C budget. The Intergovernmental Panel on Climate Change (IPCC) reported a flux term of 1.7 PgC@a-1 for 1990-1995 but more recent estimates suggest the magnitude of this source may be only of 0.96 PgC@a-1 for the 1990s. In addition, current and past land use practices are now thought to contribute to a large degree to the northern hemisphere terrestrial sink, and are the dominant driver for some regional sinks. However, mechanisms other than land use change need to be invoked in order to explain the inferred C sink in the tropics. Potential candidates are the carbon dioxide (CO2) fertilization and climate change; fertilization due to nitrogen (N) deposition is believed to be small or nil. Although the potential for managing C sinks is limited, improved land use management and new land uses such as reforestation and biomass fuel cropping, can further enhance current terrestrial C sinks. Best management practices in agriculture alone could sequester 0.4-0.8 PgC per year in soils if implemented globally. New methodologies to ensure verification and permanency of C sequestration need to be developed.

关键词： land use, terrestrial carbon, carbon emissions, sink mechanisms.

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Spatial heterogeneity of DTPA-extractable zinc in cultivated soils induced by city pollution and land use

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Science China(Life Sciences) 2005年第Z1期48卷 82-91页

作者： JIANG Yong, LIANG Wenju, WEN Dazhong, ZHANG Yuge & CHEN Wenbo Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China Shenyang Experimental Station of Ecology, Chinese Academy of Sciences, Shenyang 110016, China College of Land and Environment, Shenyang Agricultural University, Shenyang 110161, China Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Shenyang Experimental Station of Ecology Chinese Academy of Sciences Shenyang 110016 China Shenyang Experimental Station of Ecology Chinese Academy of Sciences Shenyang 110016 China College of Land and Environment Shenyang Agricultural University Shenyang 110161 China

The spatial heterogeneity of DTPA-extractable zinc in the cultivated soils of Shenyang suburbs in Liaoning Province of China was investigated, and its map was drawn by the methods of geostatistics combined with geographic information system. The data of soil DTPA-extractable zinc fitted normal distribution after logarithm transformation, and its semivariogram fitted a spherical model. The semivariogram indicated that the spatial dependence of soil DTPA-extractable zinc content was moderate, with the spatial dependence range of 1.69 km and the fractal dimension of 1.96. Stochastic factors contributed to 49.9% of the spatial variability, while structural factors contributed to 50.1% of it. The spatial heterogeneity of soil DTPA-extractable zinc shown by a kriged interpolation map was deeply influenced by stochastic factors such as city pollution, land use pattern and crop distributions. For example, the average content of Zn in vegetable garden soils was 2.5-4 times as much as in their originated soils, and was lower in paddy soils than in their originated soils. The areas with a higher content of soil DTPA-extractable zinc appeared in the near suburbs and the riverside along Hunhe River and the wastewater drainage of Xihe River, and the extremely high values in the near suburb of the city's residential area were a striking feature, indicating the key role of city pollution in the spatial heterogeneity of soil DTPA-extractable zinc. When recorded in the form of a soil pollution map,the results of such a survey make it possible to identify the unusually polluted areas, and to provide more information for precise agriculture and environmental control.

关键词： soil zinc, spatial heterogeneity, city pollution, land use, geostatisics.

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Regional differences and determinants of built-up area expansion in China

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Science China Earth Sciences 2007年第12期50卷 1835-1843页

作者： HUANG JiKun1,2,ZHU LiFen3,1 & DENG XiangZheng1,2 1 Center for Chinese Agricultural Policy,Chinese Academy of Sciences,Beijing 100101,China 2 Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China 3 Research Center of the Economy of the Upper Reaches of the Yangtze River,Chongqing Technology and Business University,Chongqing 400067,China Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Research Center of the Economy of the Upper Reaches of the Yangtze River Chongqing Technology and Business University Chongqing China

Based on remote sensing data on land use provided by the Chinese Academy of Sciences and socio-economic data collected by the authors,this paper analyzes the trends and regional differences in built-up area(BUA) expansion in China from the late 1980s to 2000,and empirically estimates the major determinants of BUA expansion in different regions in 1996―*** 1989―2000,although China's overall BUA expansion accelerated,the trends differed significantly among *** expansion in the central and western regions accelerated significantly,but it slowed down considerably in the east-ern *** estimation results from our econometric analysis reveal that BUA expansion in the eastern region reached a period when economic growth had no further significant impact on per capita BUA,the land utilization in this region has become more intensive with further expansion of the *** the central and western regions,the BUA has expanded remarkably due to the relatively more flexible land development policies and the relatively cheap land ***,as the econ-omy continues to grow rapidly,policies relating to BUA expansion and cultivated land reductions may face more serious challenges in the central and western regions.

关键词： built-up area, land use, regional difference, determinants, China

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Anti-scourability of purple soil on hillslopes with different land uses

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Science China(Technological Sciences) 2003年第Z1期46卷 133-141页

作者： ZHANG Jianhui, LIU Gangcai, NI Shijun, ZHU Bo & GE Fanglong Institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Resources, Chengdu 610041, China Chengdu University of Technology, Chengdu 610059, China Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China Chengdu Univ Technol Chengdu 610059 Peoples R China

A large-scale flume (40 cm×10 cm×10 cm) was used to determine soil anti-scourability of 4 different land uses of purple soil in hilly areas of Sichuan, China under artificial removal of vegetation to examine the effects of land uses on sediment production by runoff. The results showed that soil anti-scourability declined with the increase of slope gradients in the form of power function, but there was a significant difference in the effects of slope gradients on anti-scourability between different land uses. The ratio of the mean values of soil anti-scourability was 1︰2.2︰2.5︰3.6 for forest land, new waste pasture, old waste pasture, crop land respectively, indicating that forest and grass use can significantly improve soil anti-scourability. Compared with the observations from the runoff plots located at the same sites in this region, an inconsistent result was found between anti-scourability and anti-erodibility in hilly areas of Sichuan. Essential causes of the differences in soil anti-scourability were further discussed based on analyzing the influence of inherent soil characteristics induced by different land uses on soil anti-scourability.

关键词： sediment yield, soil anti-scourability, land use, vegetation, purple soil.

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Changes in annual CO_2 fluxes estimated from inventory data in South Korea

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Science China(Life Sciences) 2002年第Z1期45卷 87-96页

作者： Lee Dowon Yook Keun Hyung Lee Dongseon Kang Sinkyu Kang Hojeong Lim Jong Hwan Lee Kyeong Hak Environmental Planning Institute Graduate School of Environmental Studies Seoul National University Seoul 151-742 Korea School of Forestry University of Montana Missoula MT 59812 USA Department of Environmental Science and Engineering Ewha Womans University Seoul 120-750 Korea Division of Forest Ecology Korea Forest Research Institute Seoul 130-712 Korea Division of Forest Resources Korea Forest Research Institute Seoul 130-712 Korea

Using a slightly modified IPCC method, we examined changes in annual fluxes of CO2 and contributions of energy consumption, limestone use, waste combustion, land-use change, and forest growth to the fluxes in South Korea from 1990to 1997. Our method required less data and resulted in a larger estimate of CO2released by industrial processes, comparing with the original IPCC guideline. However, net CO2 emission is not substantially different from the estimates of IPCC and modified methods. Net CO2 emission is intimately related to GDP as Koreaneconomy has heavily relied on energy consumption and industrial activities, which are major sources of CO2. Total efflux of CO2 was estimated to be 63.6 Tg C/ain 1990 and amounted to 112.9 Tg C/a in 1997. Land-use change contributed to annual budget of CO2 in a relatively small portion. Carbon dioxide was sequesteredby forest biomass at the rate of 6.5 Tg C/a in 1990 and 8.5 Tg C/a in 1997. Although CO2 storage in the forests increased, the sink effect was overwhelmed by extensive energy consumption, suggesting that energy-saving strategies will be more effective in reducing CO2 emission in Korea than any other practices. It is presumed that plant uptake of CO2 is underestimated as carbon contained in plant detritus and belowground living biomass were not fully considered. Furthermore, the soil organic carbon stored in forest decomposes in various ways in rugged mountains depending on their conditions, such as slope, aspect and elevation, which could have an effect on decomposition rate and carbon stores in soils. Thus, carbon sequestration of forests deserves further attention.

关键词： CO2 emission and removal, energy consumption, forest regrowth, land use, simplified IPCC method.

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