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Chinese Geographical Science 2007年第4期17卷 349-356页

作者： WAN Rongrong yang guishan Nanjing Institute of Geography ＆ Limnology Chinese Academy of Sciences Nanjing 210008 China

Land use/cover change (LUCC) is one of the main boundary conditions which influence many hydrologic processes. In view of the importance of Taihu Lake Watershed in China and the urgency of discovering the impacts of LUCC on storm runoff, two flood events under five land cover scenarios in the Xitiaoxi River Basin of the upstream of Taihu Lake watershed were simulated by distributed hydrologic modeling system HEC-HMS. The influences of each land cover on storm runoff were discussed. It was concluded that under the same rainstorm the ascending order of runoff coefficient and peak flow produced by the 5 different land covers were woodland, shrub, grassland, arable land, and built-up land; the descending order of swelling time were woodland, shrub, grassland, arable land, and built-up land. Scenario of built-up land was the first to reach peak flow, then arable land, grassland, shrub, and woodland. There were close relationships between the runoff coefficients produced by the 5 different land covers. The degrees of impacts on runoff coefficient of land cover change modes were sorted by descending: woodland to built-up land, shrub to built-up land, grassland to built-up land, arable land to built-up land, woodland to arable land, shrub to arable land, arable land to grassland, shrub to grassland, grassland to arable land, and woodland to shrub. Urbanization will contribute to flood disaster, while forestation will mitigate flood disaster.

关键词：暴风雨径流洪水土壤流失

Non-stationary water-level fluctuation in China＇s Poyang Lake and its interactions with yangtze River

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Journal of Geographical Sciences 2015年第3期25卷 274-288页

作者： DAI Xue WAN Rongrong yang guishan Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and Limnology CAS Nanjing 210008 China University of Chinese Academy of Sciences Beijing 100049 China

Seasonal water-level fluctuations （WLF） play a dominate role in lacustrine ecosys- tems. River-lake interaction is a direct factor in changes of seasonal lake WLF, especially for those lakes naturally connected to upstream and downstream rivers. During the past decade, the modification of WLF in the Poyang Lake （the largest freshwater lake in China） has caused intensified flood and irrigation crises, reduced water availability, compromised water quality and extensive degradation of the lake ecosystem. There has been a conjecture as to whether the modification was caused by its interactions with yangtze River. In this study, we investi- gated the variations of seasonal WLF in China＇s Poyang Lake by comparing the water levels during the four distinct seasons （the dry season, the rising season, the flood season, and the retreating season） before and after 2003 when the Three Gorge Dam operated. The Water Surface Slope （WSS） was used as a representative parameter to measure the changes in river-lake interaction and its impacts on seasonal WLF. The results showed that the magni- tude of seasonal WLF has changed considerably since 2003; the seasonal WLF of the Poy- ang Lake have been significantly altered by the fact that the water levels both rise and retreat earlier in the season and lowered water levels in general. The fluctuations of river-lake in- teractions, in particular the changes during the retreating season, are mainly responsible for these variations in magnitude of seasonal WLF. This study demonstrates that WSS is a rep- resentative parameter to denote river-lake interactions, and the results indicate that more emphasis should be placed on the decrease of the Poyang Lake caused by the lowered water levels of the yangtze River, especially in the retreating season.

关键词： seasonal water-level fluctuations in lakes slope of water surface river-lake interactions Poyang Lake

Scale-free Structure of Town Road Network in Southern Jiangsu Province of China

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Chinese Geographical Science 2007年第4期17卷 311-316页

作者： SU Weizhong yang guishan YAO Shimou yang Yingbao Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Department of Material Science and Engineering of Hohai University Nanjing 210098 China

From the viewpoint of Graph Theory this paper builds a town road network graph of regional scale, and proposes numerical vertex degree (Di), rank vertex degree (Dr) and population size vertex degree (Dp) on the base of vertex degree (D). Then the indicators of Di, Dr, Dp and mathematical statistics methods are applied to investigating scale-free structure of town road networks in the southern Jiangsu Province. The results show that the distribution of Di does not exhibit scale-free properties, but Dr and Dp do. Additionally the correlation coefficient between Dp and Di is only 0.569, but the spatial correlation between Dp and Dr is very evident on the base of correlation analysis and spatial analysis of GIS. The mutual mechanism between Dp and Dr spatially represents a "Core-Belt" model of town development of regional scale. The town development model is open and clustered, and beneficial to both economic development and ecological protection. And then we suggest that Suzhou City, Wuxi City, Changzhou City and Wujin City control towns' high-density pattern by conducting centralization and consolidation policies, and properly controlling and planning higher rank roads; whereas Nanjing City, Zhenjiang City, Jintan City and Liyang City must strengthen the development of towns along higher rank roads.

关键词：江苏乡镇道路点指数道路建设

IMPACTS OF FUTURE SEA LEVEL RISE ON SALT WATER INTRUSION IN THE CHANGJIANG RIVER ESTUARY

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Chinese Geographical Science 1992年第1期2卷 31-42页

作者： yang guishan Nanjing Institute of Geography and Limnology Chinese Academy of Sciences:Nanjing 210008PRC

Sea level rise could increase the salinity of an estuary by altering the balance between fresh water and salt *** implications of sea level rise for increasing salinity have been examined in the Changjiang(yangtze)River *** correlative analysis of chlorinity,discharge and tidal level and calculation of two-dimensional chlorinity,distribution of the Changjiang River estuary,the changes of the intensity and lasting hours of salt water intrusion at Wusong Station and the changes of chlorinity distribution in the South Branch of the Changjiang River estuary have been estimated when future sea level rises 50-100 *** intensity of salt water intrusion in the future will be far more serious than current trend.

关键词： sea level rise salt water intrusion chlonnity the Changjiang River estuary

Analyzing and quantitatively evaluating the organic matter source at different ecologic zones of tidal salt marsh, North Jiangsu Province, China

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Frontiers of Environmental Science & Engineering 2008年第1期2卷 81-88页

作者： Jianhua GAO guishan yang Weixin OU Ministry of Education Key Laboratory of Coastal and Island Development Nanjing UniversityNanjing 210093China Nanjing Institute of Geography and Limnology Chinese Academic of SciencesNanjing 210008China College of Land Administration Nanjing Agricultural UniversityNanjing 210095China

In order to explore the effect of different eco-logical zones and their above plants in the organic matter cycling of the whole tidal salt marsh,indicators such as total organic carbon(TOC),total nitrogen(TN),C/N ratio,δ13C and d15N of surface,core sediments,and plants of tidal salt marshes in North Jiangsu Province are ***-quently,distribution regularities of these measurement indi-cators are discussed,and the biogeochemistry processes between sediments and plants are also ***,the organic matter sources of different ecologic zones in tidal salt marsh are evaluated,and the organic matter accumu-lations in different ecologic zones induced by their plants are also *** results indicate that TOC,TN,C/N ratio and δ13C showed obvious zonal *** organic matter sources are dominated by marine input in the silt flat,artemisia schrenkiana flat,and the transition zone between silt and spartina alterniflora flat,and are controlled by terrigenous input in spartina alterniflora *** alterniflora plays an important role in the accumulation of organic matter in the whole tidal salt marshes *** the study area,the annually increased TOC,organic matter and TN in the spartina alterniflora,artemisia schrenkiana and reed flats reach 6,451,12,043 and 536 t,*** amount of TOC,organic matter and TN accumulated in the spartina alterniflora flat is more than that in other ecological zones,which shows that the spartina alterniflora flat exert a non-replaceable effect on the material cycle and exchange in the whole tidal salt marshes ecosystem.

关键词： organic matter stable carbon and nitrogen iso-topes differentiating and analyzing North Jiangsu Province of China

Soil Moisture Response to Rainfall in Forestland and Vegetable Plot in Taihu Lake Basin,China

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Chinese Geographical Science 2015年第4期25卷 426-437页

作者： LI Qian ZHU Qing ZHENG Jinsen LIAO Kaihua yang guishan Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and Limnology Chinese Academy of Sciences University of Chinese Academy of Sciences

Soil moisture and its spatial pattern are important for understanding various hydrological,pedological,ecological and agricultural *** this study,data of rainfall and soil moisture contents at different depths(10 cm,20 cm,40 cm and 60 cm) in forestland and vegetable plot in the Taihu Lake Basin,China were monitored and analyzed for characteristics of soil moisture variation and its response to several typical rainfall *** following results were ***,great temporal variation of soil moisture was observed in the surface layer than in deeper layer in vegetable *** contrast,in forestland,soil moisture had similar variation pattern at different ***,initial soil moisture was an important factor influencing the vertical movement of soil water during rainfall *** vegetable plot,simultaneous response of soil moisture to rainfall was observed at 10-and 20-cm depths due to fast infiltration when initial soil was relatively ***,traditional downward response order occurred when initial soil was relatively ***,critical soil horizon interface was an active zone of soil water accumulation and lateral movement.A less permeable W-B soil horizon interface(40-cm depth) in vegetable plot can create perched water table above it and elevate the soil water content at the corresponding ***,the land cover was an effective control factor of soil moisture during small and moderate rainfall *** the forestland,moderate and small rainfall events had tiny influences on soil moisture due to canopy and surface O horizon ***,preferential flow and lateral subsurface interflow were important paths of soil water *** large and long duration rainfall events,lateral subsurface flow and preferential flow through surface crack or soil pipe occurred,which recharged the deep ***,in more concentrated large storm,surface crack or soil pipe connected by soil macropores was the main contributor to the occ

关键词：土壤水分含量太湖流域降雨菜地林地中国水分变化规律可持续利用规划

Water Security-based Hydrological Regime Assessment Method for Lakes with Extreme Seasonal Water Level Fluctuations：A Case Study of Poyang Lake,China

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Chinese Geographical Science 2018年第3期28卷 456-469页

作者： WAN Rongrong yang guishan DAI Xue ZHANG Yanhui LI Bing Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and Limnology Chinese Academy of SciencesNanjing 210008 China University of Chinese Academy of Sciences Beijing 100049 China Nanjing Xiaozhuang University Nanjing 211171 China

Extreme seasonal water level fluctuations characterize natural floodplain lakes in monsoon regions, which are crucial for ensuring lake water security, including flood prevention water supply and health of aquatic ecosystem. In order to achieve this goal, we established a hydrological regime assessment method based on a set of hydrological indicators for lakes with heavy seasonal water level fluctuations. The results suggest that time-sensitive hydrological indicators and specific time scales for various water security aspects must be considered. We discovered that it is more practical and meaningful to combine the water level classification derived from statistical analyses with characteristic hydrological values linked to water security. The case study of Poyang Lake results show that there are no discernable trends of Poyang Lake water regime status over the last 35 years, and the two periods of poor status are in accordance with climate variation in the lake basin area. Scholars and policy makers should focus on both floods and droughts, which are the main water security problems for Poyang Lake. It is hoped that this multi-scale and multi-element hydrological regime assessment method will provide new guidelines and methods for other international scholars of river and lake water assessment.

关键词：评价方法水平变化水文学水安全季节案例中国洪水预防

Using Fuzzy Theory and Variable Weights for Water Quality Evaluation in Poyang Lake, China

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Chinese Geographical Science 2017年第1期27卷 39-51页

作者： LI Bing yang guishan WAN Rongrong ZHANG Lu ZHANG Yanhui DAI Xue Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China University of Chinese Academy of Sciences Beijing 100049 China

Achieving water purity in Poyang Lake has become a major concern in recent years, thus appropriate evaluation of spatial and temporal water quality variations has become essential. Variations in 11 water quality parameters from 15 sampling sites in Poyang Lake were investigated from 2009 to 2012. An integrative fuzzy variable evaluation(IFVE) model based on fuzzy theory and variable weights was developed to measure variations in water quality. Results showed that: 1) only chlorophyll-a concentration and Secchi depth differed significantly among the 15 sampling sites(P yang Lake. Meanwhile, hydrological status and sewage discharged into the lake might be responsible for seasonal water quality variations.

关键词：水质评价模糊理论鄱阳湖变权中国叶绿素a浓度水质变化水质参数

Impact of seasonal water-level fluctuations on autumn vegetation in Poyang Lake wetland,China

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Frontiers of Earth Science 2019年第2期13卷 398-409页

作者： Xue DAI Rongrong WAN guishan yang Xiaolong WANG Ligang XU Yanyan LI Bing LI Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 21000& China University of Chinese Academy of Sciences Beijing 100049China Jiangsu Second Normal University Nanjing 210013China

Water level fluctuations (WLF) are natural patterns that are necessary for the survival of various plants,and WLF guarantee both the productivity and the biodiversity of ***,the underlying mechanisms of how changes in vegetation are linked to seasonal WLF remain *** vegetation and hydrological data from 1989 to 2009,we identified the key seasonal fluctuations and their impacts on vegetation in the Poyang Lake wetland by utilizing a tree-based hierarchical *** to our results: 1) WLF in summer had significant impacts on both sedges and *** severe summer floods promoted the expansion of sedges,while they inhibited the expansion of reeds;2) WLF in autumn also greatly impacted sedges,while reeds were severely affected in ***,we found that low water levels in autumn led to the expansion of sedges,and low water levels in spring led to the expansion of *** results were well corroborated through comparisons of the vegetation distribution patterns over the last two decades (i.e.,the 1990s and 2000s),which may shed light on corresponding water resource and wetland management.

关键词： wetland reeds sedges seasonal water-level fluctuations classification and regression tree model

IMPACTS OF SEA LEVEL RISE ON MAJOR PROJECTS AND URBANDEVELOPMENT IN CHINA'S COASTAL PLAINS

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Journal of Geographical Sciences 1996年第4期6卷 66-74页

作者： yang guishan Shi Yafeng(Naning Ihstitute of Goography and Lirnnology, CAS, Naning 210008 People’s Republic of China)

Due to the dual dris oftural and man-made factors, relative sea leverise in China's coastal plains can be 2 to 3 times over the global mean dunng thefirst half of the 21st Century, it will strongly whuence the vanous coastal projectsand installations and the development of coastal dhes and towns. Research resultsshow that a 50-cm-nse in relative sea leve will cause maed decline in the functionof coastal defense and drainage projects and seriously endangur the functionalworking of the vast majority of coastal harbors. Meanwhile, it will also whuence thedevelopment of coastal dhes and towns throwi deterioratin water quality of thesource of urban water supply, increasing urban fiood risk and damagin seasidetounst resources etc.. Tianin, Shanghai and Guangzhou, the three most importancoastal dhes of China, will be Strongly affeded.

关键词： China's coastal plains relative sea level rise projects and installations,urban development