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Spatial heterogeneity of the driving forces of cropland change in China

Science China Earth sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2, WANG Jinfeng1, LIU Mingliang4.1 & MENG Bin1,2,3 1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, China 2. Graduate School of the Chinese Academy of sciences, Beijing 100039, China 3. College of Arts and sciences of Beijing Union {4., Beijing 100083, China 4. School of forestry and wildlife sciences, auburn university, auburn, alabama, al36849,{12. 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the Chinese Academy of sciences 100039 Beijing China 3. School of forestry and wildlife sciences Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of Beijing Union university 100083 Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2000 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in China. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of China, natural condition changes and geographical background were the main constraints and drivers, while in Eastern China, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in China recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, China.

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Soil Inorganic Nitrogen and Microbial Biomass Carbon and Nitrogen Under Pine Plantations in Zhanggutai Sandy Soil

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Pedosphere 2008年第6期18卷 775-784页

作者： YU Zhan-Yuan CHEN Fu-Sheng ZENG De-Hui ZHAO Qiong CHEN Guang-Sheng Daqinggou Ecological Station Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China）. Life College Nanchang University Nanchang 330029 （China） Ecosystem sciences and Regional Analysis （ESRA） Lab. School of Forestry ＆Wildlife Science Auburn University Alabama 36849 （USA）

The dynamics of soil inorganic nitrogen （NH4.＋ -N and NO3^- -N） and microbial biomass carbon （Cmic） and nitrogen （Nmic） under 30-year-old fenced Pinus sylvestris L. var. mongolica Litvin （SF）, unfenced P. sylvestris L. var. mongolica Litvin （SUF）, and unfenced Pinus densiflora Siebold et Zucc. （DUF） plantations in the Zhanggutai sandy soil of China were studied during Apr. to Oct. 2004.by the in situ closed-top core incubation method. all mentioned C and N indices in each stand type fluctuated over time. The ranges of inorganic N, Cmic, and Nmic contents in the three stand types were 0.7-2.6, 4..0-12..9, and 5.4.15.2 μg g^-1, respectively. The average contents of soil NH4.＋ -N and Cmic under the three 30-year-old pine plantations were not different. However, soil NO3^ -N and total inorganic N contents decreased in the order of SUF ≥ SF ≥ DUF, the Nmic content was in the order of SF = SUF 〉 DUF, and the Cmic：Nmic ratio was in the order of SUF = DUF 〉 SF. Seasonal variations were observed in soil inorganic N, microbial biomass, and plant growth. These seasonal variations had certain correlations with microbe and plant N use in the soil, and their competition for NH4.＋ -N was mostly regulated by soil N availability. The influence of tree species on inorganic N and Nmic were mainly because of differences in litter quality. Lack of gazing decreased the Cmic：Nmic ratio owing to decreased carbon output and increased the ability of soil to supply N. The soil N supply under the P. sylvestris var. mongolica plantation was lower than under the P. densiflora plantation.

关键词： ecosystem management Horqin sandy land soil nitrogen availability Pinus densiflora Pinus sylvestris vat. mongoliea

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THE GROUND CENSUSES ON RED-CROWNED CRANE IN KHANKA LAKES DISTRICT OF CHINA

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Journal of Northeast forestry university 1991年第2期2卷 83-88页

作者： Piao RenzhuInstitute of wildlife of Heilongjiang Province Sun Sen An Dongdong Northeast forestry university 1. Institute of wildlife of Heilongjiang Province China 2. Northeast forestry university China

Coordination of the aerial servey, the author carried ground census on the population size of Red-crowned crane(Grus japonensis) in Khanka Lakes District from 1984.to 1986. According to the census in spring of 1984. the total number of Red-crowned crane is 72 individuals and 20 nests. So that this ground census has recorded 59 individuals more than the aerial survey of 13 individuals, and the percentage of nesting individuals in this flock is 55.6%, which is obviously higher than 36.9% of the average ratio in China. After this, in fall of 1984.and in spring of 1985 and 1986, we repeated the same censuses three times in the same districts, the results indicated that the flock of the crane in Khanka Lakes District is stable basically, but some individuals interchange with opposite flock of USSR because of gcgraphical ***, we believe this flock in China and that flock in USSR belong to the same population and suggest two countries should act in concert to studing on this population in future. Meanwhile, the aerial servey cooperate with ground census, it is the best way for reducing missing crane and achieving to high precision of census. From this, total number of Red-crowned crane in China is 54. individuals (4.3+59 ind ividuals).

关键词： Red-crowned crane Ground census Population size Khanka Lakes district

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Quantifying soil erosion with GIS-based RUSLE under different forest management options in Jianchang Forest Farm

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中国科学：技术科学英文版 2006年第z1期49卷 160-166页

作者： ZHANG Hengming, WANG Qingli, DAI Limin, Guofan Shao, TANG Una, WANG Shunzhong & GU Huiyan Institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110016, China Graduate university of Chinese Academy of sciences, Beijing 100101, China Department of forestry and Natural Resources, Purdue university, Lafayette IN4.901, usa Northeast forestry university, Harbin 15004., China Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate university of Chinese Academy of sciences Beijing 100101 China Department of forestry Natural Resources Purdue University Lafayette IN 47901 USA Northeast forestry university Harbin 150040 China

Quantitatively estimating soil erosion with an integration of geographic information system (GIS) and the revised universal soil loss equation (RUSLE) under four different exposed soil proportion scenarios caused by forest management practices was studied at Jianchang Forest Farm. The GIS provided means of input data generation required by RUSLE model and allowed a spatial assessment of the erosion hazard over the study area. Four exposed soil proportion scenarios of 5%, 10%, 20% and 30% were tested with the GIS-based RUSLE model to evaluate soil erosion hazard. The predicted soil erosion potentials were classified into five categories in order to provide valuable aids for management planning.

关键词： geographic information system, RUSLE, soil erosion, forest management.

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The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science China Earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4. LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic sciences and Natural Resources Re-search, Chinese Academy of sciences, Beijing 100101, China 2. Institute of forestry, Chinese Academy of forestry sciences, Beijing 100091, China 3. Department of Civil Engineering, university of Hong Kong, Hong Kong, China 4. Eco-environmental Research Center, Chinese Academy of sciences, Beijing 100085, China 5. College of Resources and Environment, Southwest Agricultural university, Chongqing 4.0716, China Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. Department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4. less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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Digital forestry research in China

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Science China(Technological sciences) 2006年第z1期49卷 1-8页

作者： TANG Shouzheng, TANG Una, Guofan Shao & DAI Limin Research Institute of Resource Information Techniques, Chinese Academy of forestry, Beijing 100091, China Institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110016, China Departmet of forestry and Natural Resources, Purdue university, West Lafayette, IN 4.907,{4. Graduate university, Chinese Academy of sciences, Beijing 100101, China Research Institute of Resource Information Techniques Chinese Academy of Forestry Beijing 100091 China Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Department of forestry Natural Resources Purdue University West Lafayette IN 47907 USA Graduate university Chinese Academy of Sciences Beijing 100101 China

Digital forestry as a concept was developed after the Digital Earth program. The Chinese scientists were not only among the pioneers who first proposed the concept of Digital forestry, but also contributed a lot to the development of Digital forestry. Digital forestry is a digital framework to maintain forest planting, management, using, and protect. The synergetic use of computationally-intensive quantitative methods together with information technologies is the most important foundation for the development of Digital forestry. Under this situation, the experience of Digital forestry development in China is relatively rich. A number of academicians, scholars, and professional administrators were involved in discussing the Digital forestry Construction Scheme. The Project of Digital forestry Practicability approved by the State forestry Administration is a major instance in developing Digital forestry standard and key techniques. By introducing a case study of Digital forestry, this paper reviews the concept of Digital forestry, the way turning traditional forestry into Digital forestry, and the future development of Digital forestry.

关键词： Digital Forest, Digital Earth, Digital forestry standard, Digital forestry techniques.

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The roles of a decision support system in applying forest ecosystem management in Northeast China

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Science China(Technological sciences) 2006年第z1期49卷 9-18页

作者： DAI Limin, ZHENG Bofu, Guofan Shao & ZHOU Li State Key Lab of Systems Ecology, Research Center for Eco-Environmental sciences, Chinese Academy of sciences, Beijing 100085, China Institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110016, China Department of forestry and Natural Resources, Purdue {4., West Lafayette, IN 4.907, usa Graduate {4. of Chinese Academy of sciences, Beijing 100101, China 1. State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China2. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China3. Department of Forestry and Natural Resources Purdue University West Lafayette IN 47907 USA4. Graduate University of Chinese Academy of Sciences Beijing 100101 China

Forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in China is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools available to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, FORESTAR, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of FORESTAR.

关键词： forest functions, forested landscapes, forest services, forest models, geographic information systems.

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Relation of Mineralizable N to Organic N Components in Dark Loessial Soils

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Pedosphere 2003年第3期13卷 279-288页

作者： LI JUMEI and LI SHENGXIUCollege of Natural Resources and Environmental sciences, Northwestern Science and Technology university of Agriculture and forestry, Yangling, Shaanxi 712.00 (China) College of Natural Resources and Environmental sciences Northwestern Science and Technology University of Agriculture and Forestry Yangling Shaanxi 712100 (China)

Mineralizable N and organic N components in different layers (0～15, 15～30,30～4., 4.～60, 60～80 and 80～100 cm) of six soils with different fertilities sampled from YongshouCounty, Shaanxi Province, China, were determined by the aerobic incubation method and the Bremnerprocedure, respectively. Correlation, multiple regression and path analyses were performed to studythe relation of mineralizable N to organic N components. Results of correlation and regressionanalyses showed that the amounts of the N mineralized were parallel to, and significantly correlatedwith, the total acid hydrolyzable N, but was not so with the acid-insoluble N. Of the hydrolyzableN, the amino acid N and the ammonia N had a highly consistent significant correlation with themineralized N, and their partial regression coefficients were significant in the regressionequations, showing their importance in contribution to the mineralizable N. The amino sugar N, onthe other hand, had a relatively high correlation with the mineralized N, but their partialregression coefficients were not significant in the regression equations. In contrast, thehydrolyzable unknown N had no such relations. Path analysis further indicated that the amino acid Nand ammonia N made great direct contributions to the mineralized N, but the contributions of theamino sugar N were very low. These strongly suggested that the mineralized N in the soils tested wasmainly from the hydrolyzable N, particularly the amino acid N and ammonia N which are the majorsources for its production.

关键词： acid-insoluble N hydrolyzable N mineralizable N organic N component

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Digitally determining forest inventory units with an ecological classification system

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Science China(Technological sciences) 2006年第z1期49卷 118-127页

作者： TANG Una, WANG Qingli, Guofan Shao, DAI Limin, WANG Shunzhong, LI Xiufen & XU Dong Institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110016, China Graduate university of Chinese Academy of sciences, Beijing 100101, China Department of forestry and Natural Resources, Purdue university, West Lafayette, IN 4.907, usa 1. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. Graduate university of Chinese Academy of sciences Beijing 100101 China 3. Department of forestry and Natural Resources Purdue University West Lafayette IN 47907 USA

Management-level forest resource data in China were obtained with a combination of two forest inventories. However, inconsistencies in the spatial attributes of forest data vary between the two inventory types and between two inventories of the same type. The inconsistencies make it inconvenient for long-term forest management planning with digital technologies. Ecological Land Types (ELTs) and Ecological Land Type Phases (ELTPs) have been mapped in selected forestry regions in northeast China, where important forest industries are located. The boundaries of ELTs are determined by geomorphic conditions, which are quantified by Digital Elevation Models (DEM); ELTPs are classified by overlaying ELTs with forest vegetation data layers that are obtained with both remotely sensed and ground data. The ELTPs represent the divisions of land in terms of both natural and human-induced forest conditions, and therefore they are reliable units for forest inventories and management. This paper introduces a case study for digitally determining forest inventory units in Benxi City, Liaoning Province, northeast China. The general objective of the study was to explain how a compatible forest inventory system should be designed and why the compatible forest inventory system was significant to digital forestry in China.

关键词： forest inventory, ecological classification, ELT mapping, ELTP mapping, geographic information systems, forest management.

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GIS-based analysis of forest degradations in Baihe forestry Bureau,northeast China

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Science China(Technological sciences) 2006年第z1期49卷 167-176页

作者： ZHOU Li, DAI Limin , Guofan Shao, XU Dong, WANG Hui & BAI Jianwei Institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110016, China Graduate university of Chinese Academy of sciences, Beijing 100101, China Department of forestry and Natural Resources, Purdue university, West Lafayette, IN 4.907, usa Department of City Development, Jinan university, Jinan 250002, China Academy of Forest Inventory and Planning, State forestry Administration, Beijing 100714. China 1. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. Graduate university of Chinese Academy of sciences Beijing 100101 China 3. Department of forestry and Natural Resources Purdue University West Lafayette IN 47907 USA 4. Department of City Development Jinan University Jinan 250002 China 5. Academy of Forest Inventory and Planning State Forestry Administration Beijing 100714 China

Forests in the Changbai Mountains are important timber sources for economic development of the society and provide ecological services in northeast China. In order to strengthen forest resource management, this paper analyzed management-induced changes in forest structure, tree species composition and forest landscape pattern from 1987 to 2000 for Baihe forestry Bureau in Jilin Province based on digitized forest parcel maps and forest survey data. The results suggested that the area of Mature, High-Stocking, and Close-Canopy Forests decreased by 31.4., 55.9% and 10.7% respectively; volume of Mixed Forest, the native forest vegetation type, decreased by 17.8%;the number of patches increased tremendously but the mean patch density decreased sharply for Mature, High-Stocking, Close-Canopy, and Mixed Forests. all the changes in forest structure, species composition, and landscape pattern indicated severe degradations going on with the forests in Baihe forestry Bureau. Because of the effect of degradation to forest services, restoring forest resources and protecting biodiversity has become urgently important. The strategies of sustainable forest management need to be worked out and implemented.

关键词： geographic information system, forest management, Changbai Mountains, forest change, forest decline.

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