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Science China Earth sciences 2004年第8期47卷 749-759页

作者： zhang Shuqing1, zhang Junyan1,2 & zhang bai1 northeast institute of geography and Agricultural Ecology, chinese academy of sciences, changchun 130012, China northeast Design institute of China City Planning and Engineering, changchun 130012, China 1. northeast institute of geography and Agricultural Ecology Chinese Academy of Sciences 130012 Changchun China 2. northeast Design institute of China City Planning and Engineering 130012 Changchun China

By combining geographic information system (GIS), a new conception of “group” in which covers the complex connected region is introduced in the paper. Based on the conception of group, a generalized Euler formula and its properties are deduced and proved. The paper also describes the mathematical principles of generating topological information of polygon in GIS maps and the methods for checking up the veracity of topological relations of the map with Euler formula and general Euler formula. We have also obtained the quantitative relations among real nodes, chains, islands and groups with the formulas. At the same time, the paper introduces Whole Sphere Stereographic (WSS) projection into the GIS, and defines a new conception of “sea”. The deduction of general Euler formula and the introduction of WSS projection to GIS have developed new ways of delineating GIS topological models from plane to sphere and even constructing three dimensional (3-D) topological models.

关键词： Euler formula,general Euler formula,geographic information system,topological relation.

Spatial Variability of Soil Organic Carbon Under Maize Monoculture in the Song-Nen Plain, northeast China

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Pedosphere 2010年第1期20卷 80-89页

作者： WANG Zong-Ming , zhang bai, SONG Kai-Shan, LIU Dian-Wei and REN Chun-Ying northeast institute of geography and Agricultural Ecology, chinese academy of sciences, changchun 130012 (China) [a] northeast institute of geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 (China)

Soil organic carbon (SOC) and its relationship with landscape attributes are important for evaluating current regional, continental, and global carbon stores. Data of SOC in surface soils (0–20 cm) of four main soils, Cambisol, Arenosol, Phaeozem, and Chernozem, were collected at 451 locations in Nongan County under maize monoculture in the Song-Nen Plain, northeast China. The spatial characteristics of soil organic carbon were studied, using geographic information systems (GIS) and geostatistics. Effects of other soil physical and chemical properties, elevation, slope, and soil type on SOC were explored. SOC concentrations followed a normal distribution, with an arithmetic mean of 14.91 g kg-1 . The experimental variogram of SOC was fitted with a spherical model. There were significant correlations between soil organic carbon and bulk density (r =-0.374**), pH (r = 0.549**), total nitrogen (r = 0.781**), extractable phosphorus (r =-0.109*), exchangeable potassium (r = 0.565**), and cation exchange capacity (r = 0.313**). Generally, lower SOC concentrations were significantly associated with high elevation (r =-0.429**). Soil organic carbon was significantly negatively correlated with slope gradient (r =-0.195**). Samples of the Cambisol statistically had the highest SOC concentrations, and samples of the Arenosol had the lowest SOC value.

关键词： geostatistics slope soil bulk density spatial distribution

LAND RECLAMATION PROCESS IN northeast CHINA SINCE 1900

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chinese Geographical Science 2003年第2期13卷 119-123页

作者： zhang bai, CUI Hai-shan, YU Lei, HE Yan-fen (northeast institute of geography and Agricultural Ecology, chinese academy of sciences, changchun 130012,P.R.China) northeast institute of geography and Agricultural Ecology Chinese Academy of Sciences Changchun P. R. China

northeast China is an important agricultural region in China. The northeastPlain is the largest plain in the country and one of the three famous black soil zones in the *** of fertility of the soil, however, large-scale agricultural development mainly took placesince 1900. The land exploitation and utilization has been fast and intensive in this region sincethen and change in the land-cover process has been remarkable. Both national and internationalresearchers on land use and land cover are paying more attention to these processes in this regionand their implication for local ecological environment. This article discusses the land reclamationprocesses and their main driving forces in northeast China since 1900. According to the research,the 20th century was the most important period for land reclamation in northeast China. In theseyears the rate, intensity and quantity of land reclamation have been staggering, and more than 100000km^2 of land was converted into farmland. This magnitude of land reclamation inland is unique inthe world. Research on the land reclamation of northeast China can provide some data on the effectof human activity on environment. As in many other places in the world, the primary driving force ofreclamation in northeast China was the increasing pressure of population. In the 20th century thepopulation increased from 10 x 10~6 to 110 x 10~6 in northeast China and from 400 x 10~6 to 1. 3 x10^9 in China. Population pressure is thus the most important driving force for land reclamation.

关键词： land reclamation process northeast china 20th century

RS-and-GIS-Supported Forecast of Grassland Degradation in Southwest Songnen Plain by Markov Model

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Geo-Spatial Information Science 2005年第2期8卷 104-109页

作者： LI Jianping zhang bai GAO FengLI Jianping,Ph.D candidate, northeast institute of geography and Agriculture Ecology,CAS,changchun 130012 Postgraduate School of the chinese academy of sciences,Beijing 100039,China. northeast institute of geography and Agriculture Ecology CAS Postgraduate School of the chinese academy of sciences

By taking Daan city in Jilin Province as a research object and by using TM image in 1989 and ETM + image in 2001 from American LANDSAT satellite,all kinds of maps and documentation,information of grassland,saline-alkalized land,cropland,water area and forestland is extracted by man-computer interactive interpretation method with ArcView and ArcInfo GIS software, and statistics data is acquired. On the basis of this the changing trend of land use types in the next ten years is forecasted and analyzed with Markov model. The results indicate that the problem of grassland degradation in the study area is quite serious.

关键词： remote sensing geographic information system grassland degradation imageinterpretation markov model

DYNAMIC CHANGES OF THE WETLAND AND ITS DRIVING FORCES IN FUJIN REGION IN SANJIANG PLAIN,CHINA

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湿地科学 2005年第3期3卷 176-182页

作者： WANG Zhi-Qiang~1,2, CHEN Ming~1,2,WANG Dan-Dan~1,2 , zhang bai~1,zhang Shu-Qing~1(1. northeast institute of geography and Agricultural Ecology, the chinese academy of sciences,changchun Jilin 130012, China 2. Graduate School of chinese academy of sciences, Beijing 100039, China ) northeast institute of geography and Agricultural Ecology the Chinese Academy of SciencesChangchun Jilin 130012China Graduate School of chinese academy of sciences Beijing 100039China northeast institute of geography and Agricultural Ecology the Chinese Academy of SciencesChangchun Jilin 130012China

Wetland is a kind of key natural resources. However, the wetlands have been shrinking rapidly in Sangjiang Plain and its functions have been degrading. These all hold back the sustainable development of human communities, and lead to great change in the land use /cover (LUCC), consequently caused global changes in climate, water cycling, etc.. Taken Fujin region as a case study, spatial and temporal dynamic processes of wetland and its driving forces were analyzed from 1954 to 2000 in this paper. It showed that the wetlands had been reduced from 52×104 ha to 11×104 ha in areas during the nearly 50 years . The percentage of wetland areas reduced from 61.27% to 12.39%. On the other hand, cultivated land increased from 22×104 ha to 60×104 ha in areas. The percentage of the areas increased from 25.31% to 70.45%. Further quantitative analysis of the wetland landscape conversion characteristics and the correlation analysis between the change of wetland areas and population increase were made. The results showed that 40×104 ha wetlands had been converted to cultivated land within half of a century; the correlation between the rate of wetland loss and that of population increased is nearly -0.922. So it was concluded that the main driving force of wetland shrinkage in Fujin region was the colonization of human being.

关键词：湿地动态变化三江平原生态系统生态环境

Estimating Soil Erosion in northeast China Using ^(137)Cs and ^(210)Pbex

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Pedosphere 2011年第6期21卷 706-711页

作者： YANG Yu-Hong YAN bai-Xing ZHU Hui Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 （China） College of Water Resources North China University of Water Resources and Electric Power Zhengzhou 450011 （China）

Evaluation of soil erosion in agricultural fields is valuable to develop conservation practices for reducing agricultural nonpoint source pollution. Soil erosion rates were quantified using the fallout radionuclide tracer technique in Mojiagou Basin located on the outskirts of changchun in northeast China. The calculated soft erosion rates in the study area were 1.99 and 1.85 mm year-1 using 137Cs and excess 210pb （210Pbex） measurements, respectively. Both fallout radionuclides showed a similar tendency at downslope sites. All measured sites have experienced net erosion during the past 50 to 100 years. 137Cs and 210Pbex measurements were useful to quantify soil erosion rates on field and small basin scales. At this rate of erosion, the current fertile topsoil layer would be entirely removed within 70 years.

关键词： black soil fallout radionuclide tracer technique rainfall erosivity reference inventory soil loss

Conceptualizing and Measuring Economic Resilience of Resource-based Cities： Case Study of northeast China

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chinese Geographical Science 2017年第3期27卷 471-481页

作者： TAN Juntao zhang Pingyu LO Kevin LI Jing LIU Shiwei northeast institute of geography and agroecology Chinese Academy of Sciences Jilin Changchun 130102 China University ofchinese academy of sciences Beijing 100049 China Department of geography Hong Kong Baptist University Hong Kong China

This paper develops a conceptual model and an indicator system for measuring economic resilience of resource-based cities based on the theory of evolutionary resilience and the related concepts of persistence, adaptation, and transformation. Nineteen resource-based cities in northeast China were analyzed using the indicator system. The results showed that Liaoning and Jilin provinces had higher economic resilience than Heilongjiang Province. Panjin, Benxi, and Anshan in Liaoning Province were the top three cities, while Shuangyashan and other coal-based cities in Heilongjiang Province ranked last. Metals-and petroleum-based cities had significantly higher resilience than coal-based cities. The differences in persistence, adaptability, transformation, and resilience among resource-based cities decreased since the introduction of the northeast Revitalization Strategy in 2003. Forestry-based cities improved the most in terms of resilience, followed by metals-based and multiple-resource cities; however, resilience dropped for coal-based cities, and petroleum-based cities falling the most. The findings illustrate the importance and the way to develop a differentiated approach to improve resilience among resource-based cities.

关键词： resource-based cities economic resilience northeast China

Adsorption and Desorption of Ammonium in Wetland Soils Subject to Freeze-Thaw Cycles

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Pedosphere 2011年第2期21卷 251-258页

作者： YU Xiao-Fei zhang Yu-Xia ZOU Yuan-Chun ZHAO Hong-Mei LU Xian-Guo WANG Guo-Ping northeast institute of geography and agroecology Chinese Academy of Sciences Changehun 130012 (China) Graduate University of chinese academy of sciences Beijing 100049 (China)

Nitrogen （N） cycling in boreal peatland ecosystems may be influenced in important ways by freeze-thaw cycles （FTCs）. Adsorption and desorption of ammonium ions （NH4＋） were examined in a controlled laboratory experiment for soils sampled from palustrine wetland, riverine wetland, and farmland reclaimed from natural wetland in response to the number of FTCs. The results indicate that freeze-thaw significantly increased the adsorption capacity of NH： and reduced the desorption potential of NH4＋ in the wetland soils. There were significant differences in the NH4＋ adsorption amount between the soils with and without freeze-thaw treatment. The adsorption amount of NH4＋ increased with increasing FTCs. The palustrine wetland soil had a greater adsorption capacity and a weaker desorption potential of NH4＋ than the riverine wetland soil because of the significantly higher clay content and cation exchange capacity （CEC） of the riverine wetland soil. Because of the altered soil physical and chemical properties and hydroperiods, the adsorption capacity of NH4＋ was smaller in the farmland soil than in the wetland soils, while the desorption potential of the farmland soil was higher than that of the wetland soils. Thus, wetland reclamation would decrease adsorption capacity and increase desorption potential of NH4＋, which could result in N loss from the farmland soil. FTCs might mitigate N loss from soils and reduce the risk of water pollution in downstream ecosystems.

关键词： cation exchange capacity clay content farmland hydroperiod N loss

Using remote sensing to research Beijing wetlands dynamics

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Science China(Technological sciences) 2006年第z2期49卷 97-107页

作者： ZHAO Wenji, GONG Zhaoning, GONG Huili, LI Xiaojuan, zhang Songmei & LI Jing Key Lab of Resource Environment and GIS of Beijing, Capital Normal University, Beijing 100037, China northeast institute of geography and agroecology, chinese academy of sciences, changchun 130012, China College of Resources Science and Technology, Beijing Normal University, Beijing 100875, China Capital Normal Univ Key Lab Resource Environm Beijing 100037 Peoples R China Capital Normal Univ GIS Beijing Beijing 100037 Peoples R China chinese Acad Sci NE Inst Geog & Agroecol Changchun 130012 Peoples R China Beijing Normal Univ Coll Resources Sci & Technol Beijing 100875 Peoples R China

In Beijing, where wetlands are important to municipal freshwater conservation and biodiversity retention, three different types of wetlands were identified: riverside wetlands, wetlands surrounding lakes and reservoirs, and wetlands in municipal *** sensing technology was applied in combination with field investigations to monitor and analyze the changes in these wetlands, and a combination of fusion technologies,Landsat TM/ETM+ and IKONOS imaging, was used to investigate and map them. This study indicates that not only have wetland areas been reduced by half, but also their ecological environments have been degraded because of rapid economic development and population increase. Suggestions based on this research are made to reconstruct the ecological environment of the wetlands and return them to their previous state.

关键词： Beijing, wetland resource, remote sensing technology, ecological environment, dynamics.