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您的检索式：作者名="Shujin Deng"
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| 1 | Simulation on the dynamics of forest area changes in Northeast China显示文摘There is plenty of forests in Northeast China which contributes a lot to the conservation of water and land resources, produces timber products, and provides habitats for a huge number of wild animals and plants. With changes of socio-economic factors as well as the geophysical conditions, there are dramatic changes on the spatial patterns of forest area. In this sense, it is of great significance to shed light on the dynamics of forest area changes to find the underlining reasons for shaping the changing patterns of forest area in Northeast China. To explore the dynamics of forest area change in Northeast China, an econometric model is developed which is composed of three equations identifying forestry production, conversion from open forest to closed forest and conversion from other land uses to closed forest so as to explore the impacts on the forest area changes from demographic, social, economic, location and geophysical factors. On this basis, we employ the Dynamics of Land System (DLS) model to simulate land-use conversions between forest area and non-forest cover and the land-use conversions within the sub-classes of forest area for the period 2000–2020 under business as usual scenario, environmental protection scenario and economic growth scenario. The simulation results show that forest area will expand continuously and there exist various kinds of changing patterns for the sub-classes of forest area, for example, closed forest will expand continuously and open forest and shrub will decrease a little bit, while area of other forest will keep intact. The research results provide meaningful decision-making information for conserving and exploiting the forest resources and making out the planning for forestry production in the Northeast China region. | DENG Xiangzheng JIANG Qun'ou ZHAN Jinyan HE Shujin LIN Yingzhi | 2010 | Journal of Geographical Sciences2010，20，4： | 11 |
| 2 | Estimation of Land Production and Its Response to Cultivated Land Conversion in North China Plain显示文摘Food safety and its related influencing factors in China are the hot research topics currently,and cultivated land conversion is one of the significant factors influencing food safety in China.Taking the North China Plain as the study area,this paper examines the changes of cultivated land area using satellite images,estimates land productivity from 1985 to 2005 using the model of Estimation System for Land Productivity(ESLP),and analyzes the impact of cultivated land conversion on the land production.Compared with the grain yield data from statistical yearbooks,the results indicate that ESLP model is an effective tool for estimating land productivity.Land productivity in the North China Plain showed a slight decreasing trend from 1985 to 2005,spatially,increased from the north to the south gradu-ally,and the net changes varied in different areas.Cultivated land area recorded a marginal decrease of 8.0 × 105 ha,mainly converted to other land uses.Cultivated land conversion had more significant negative impacts on land produc-tion than land productivity did.Land production decreased by about 6.48 × 106 t caused by cultivated land conversion between 1985 and 2005,accounting for 91.9% of the total land production reduction.Although the land productivity increased in Anhui and Jiangsu provinces,it can not offset the overall adverse effects caused by cultivated land con-version.Therefore,there are significant meanings to control the cultivated land conversion and improve the land pro-ductivity for ensuring the land production in the North China Plain. | JIANG Qun'ou DENG Xiangzheng ZHAN Jinyan HE Shujin | 2011 | Chinese Geographical Science2011，21，6： | 6 |
| 3 | Light induced space-time patterns in a superfluid Fermi gas显示文摘Patterns resulted from modulation instability are ubiquitous and have been extensively studied in optics and Bose-Einstein condensates. However, these patterns have not been realized in ultracold Fermi gases, although there has been considerable theoretical interest in this field. Here we report an experimental observation of space-time patterns in a superfluid Fermi gas excited by red-detuned laser light. Longitudinal spatially fluctuated laser beams induce the spontaneous formation of two different kinds of patterns. For strongly interacting Fermi gas, the induced patterns accompanied by phonon excitations demonstrate a striking'X'-type dispersion relation between frequency and wavevector. Then, the propagation of such patterns in the Bose-Einstein condensate to Bardeen-Cooper-Schrieffer crossover is investigated, which is related to the speed of sound and agrees well with theoretical calculations. The observed patterns in noninteracting Fermi gases are stationary without phonon excitations and show a much longer lifetime. | Fang Li Shujin Deng Liang Zhang Jiahui Xia Licheng Yi Haibin Wu | 2021 | Science China(Physics,Mechanics & Astronomy)2021，64，9： | 0 |
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