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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 university, Beijing 100083, China 4. school of forestry and wildlife sciences, auburn university, auburn, alabama, al3684., usa 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..0-128.9, 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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Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

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Science China(Technological sciences) 2006年第z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui Institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110016, China school of forestry, Northeast forestry {4., Harbin 15004., China State Key Lab of Systems Ecology, Research Center for Eco-Environmental sciences, Chinese Academy of sciences, Beijing 100085, China Graduate {4. of Chinese Academy of sciences, Beijing 100039, China 1. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. school of forestry Northeast Forestry University Harbin 150040 China 3. State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 4. Graduate university of Chinese Academy of sciences Beijing 100039 China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of China (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was4..2%, much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

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Comparative study on using carbon or nitrogen limited medium to culture white rot fungi for reactive brilliant red dye K-2BP decolotization under non-sterile conditions

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Science China Chemistry 2007年第5期50卷 718-724页

作者： GAO DaWen1,2, WEN XiangHua1 & QIAN Yi1 1 State Key Joint Laboratory of Environmental Simulation and Pollution Control, Department of Environment Science and Engi- neering, Tsinghua university, Beijing 100084. China 2 school of forestry, Northeast forestry university, Harbin 15004., China State Key Joint Laboratory of Environmental Simulation and PollutionControl Department of Environment Science and EngineeringTsinghua UniversityBeijing100084China school of forestry Northeast Forestry UniversityHarbin 150040China

In order to explore ways for the application of white rot fungus in dye effluent treatment under non-sterile conditions, experiment on decolorization of reactive brilliant red was carried out, employing nitrogen-limited and carbon-limited medium with C/N ratio of 56/2.2 and 28/4. (in mmol/L), respectively. The results showed that the decolorization rate reached 92% while culturing white rot fungus with ni- trogen-limited medium; however, the decolorization process ended in carbon-limited medium (n(C)/n(N) = 28/4.) because of bacterial contamination. In addition, pH rose up to 9.31 after 4.d of decolorization, which was caused by bacterial contamination in the carbon-limited system. Therefore, it is concluded that nitrogen-limited medium can inhibit bacterial growth to some extent while carbon-limited medium is more easily contaminated by bacteria. Nitrogen-limited medium is more suitable in culture of white rot fungus for decolorization of reactive dye. Medium with the ability of inhibiting yeast growth should be developed by adjusting other components of nitrogen-limited medium.

关键词： white rot fungus, Phanerochaete chrysosporium, non-sterile, decolorization, dye

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Characteristics of N Mineralization in Urban Soils of Hefei,East China

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Pedosphere 2010年第2期20卷 236-244页

作者： ZHANG Kai,XU Xiao-Niu and WANG Qin school of forestry and Landscape Architecture,Anhui Agricultural university,Hefei 230036 (China) [a] school of forestry and Landscape Architecture Anhui Agricultural University Hefei 230036 (China)

Nitrogen cycling has been poorly characterized in urban *** in-situ buried bag incubation technique was used to quantify net rates of N mineralization and nitrification in soils of two urban sites,a street greening belt and a university campus,and a suburban site,a forest park,in Hefei,East *** average concentration of extractable NO 3 in the surface soil (0-10 cm) was significantly higher at the urban sites than the suburban park site,whereas extractable NH + 4.concentration was significantly higher at the suburban park site than the urban *** forest park soil had greater potential N mineralization (14..1 μg N cm 3) than the soils from the campus (138.3 μg N cm 3) and street (99.8 μg N cm 3).The net mineralization rates varied between 1.63 and 2.69 μg N cm 3 d 1 and net nitrification rates between 0.82 and 1.02 μg N cm 3 d 1 at the suburban forest park site,but the rates varied from 1.27 to 2.4. μg N cm 3 d 1 and from 1.07 to 1.4. μg N cm 3 d 1,respectively,at the urban campus *** net mineralization and nitrification rates were lower during dry *** from regression analysis indicated that net N mineralization was significantly and positively correlated with soil moisture and soil C/N ratio,and was negatively correlated with soil *** nitrification was,however,significantly and negatively correlated with soil moisture and soil C/N ratio,and was positively correlated with soil *** relative nitrification was 0.763,indicating the dominance of nitrate cycling relative to ammonium cycling at the urban *** urban soils had the great potential for N losses compared to the suburban soils.

关键词： nitrification nitrogen cycling soil properties

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REGULATION OF PHYTOHORMONS ON THE REGENERATION OF SHOOT-TIPS OF ANTIRRHINUM MAJUS INTO PLANTLET IN VITRO

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Journal of Northeast forestry university 1992年第1期3卷 16-22页

作者： Zhang XiaofangNortheast forestry universityXin YafenJilin forestry schoolLiu HongweiNortheast forestry university 1. Northeast forestry university China 2. Jilin forestry school China

Tissue culture of Antirrhium majus was experimented by using the tip of shoots as the explants, and comparing the effects of NAA, IAA and 2, 4.D on the formation of adventitious buds. The results indicated that the effect of NAA was the best for the formation of adventitious buds, 5.0, 7.0, 9.0, 11.0, 13.0 mg/L BA combinatcd with 0.1, 0.5, 1.0, 1.5, 2.0 mg/L NAA respectively. The results show that combinations of the concentrations of BA 7.0-9.0 mg/L and NAA 0.1-0.5 mg/L were advantageous to the regeneration of buds and NAA was very important for callus growth.

关键词： Antirrhinum majus Phytohormons Regeneration of plantlet Adventitious bud

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Analysis of forest backscattering characteristics based on polarization coherence tomography

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Science China(Technological sciences) 2010年第S1期53卷 166-175页

作者： LUO HuanMin 1,LI XiaoWen 1,2,CHEN ErXue 3,CHENG Jian 4.& CAO ChunXiang 21 Institute of Geo-Spatial Information Science and Technology,university of Electronic Science and Technology of China,Chengdu 610054.China 2 State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of sciences and Beijing Normal university,Beijing 100101,China 3Institute of Forest Resources Information Technique of Chinese Academy of forestry,Beijing 100091,China 4.{4. of Electronic Engineering,university of Electronic Science and Technology of China,Chengdu 610054.China State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Beijing Normal Univ Beijing 100101 Peoples R China Univ Elect Sci & Technol China Inst Geospatial Informat Sci & Technol Chengdu 610054 Peoples R China Chinese Acad forestry Inst Forest Resources Informat Tech Beijing 100091 Peoples R China Univ Elect Sci & Technol China Sch Elect Engn Chengdu 610054 Peoples R China

It is difficult to make an inventory of vertical profiles of forest structure parameters in field ***,analysis and understanding of forest backscattering characteristics contribute to estimation and detection of forest vertical structure because of the close relationships between backscattering characteristics and structure *** vertical structure function in the complex interferometric coherence definition,which represents the vertical variation of microwave scattering with the penetration depth at a point in the 2-D radar image and can be used to analyze the forest backscattering characteristics,can be reconstructed from polarization coherence tomography(PCT).Based on PCT,the paper analyzes the forest backscattering characteristics and explores the inherent relationship between the result of PCT and the forest structure parameters from numerical simulation of Random Volume over Ground model(RVoG),Polarimetric SAR interferometry(PolInSAR)simulation of forest scene and PolInSAR data at L-band of the test site ***,the effects of the extinction coefficient and surface-to-volume scattering ratio in RVoG model on vertical backscattering characteristics are analyzed by means of numerical ***,by applying PCT to L-band POLInSAR simulations of forest scene,different variations of vertical backscattering due to different extinction coefficients and the ratios of surface-to-volume scattering resulting from different polarizations,forest types and densities are displayed and *** a concept of relative average backscattering intensity is presented,and the factors which affect its vertical distribution are also *** results show that there is high sensitivity of the vertical distribution of forest relative average backscattering intensity to the polarization,forest type and ***,based on repeat pass DLR E-SAR L-band airborne POLInSAR data,the capability of PCT technology for detection

关键词： backscattering characteristic POLInSAR PCT vertical structure function

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Characterization of a novel developmentally retarded mutant (drm1) associated with the autonomous flowering pathway in Arabidopsis

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Cell Research 2005年第2期15卷 133-140页

作者： Yong ZHU1,2,*, Hui Fang ZHAO1,3,*, Guo Dong REN1, Xiao Fei YU1, Shu Qing CAO1, Ben Ke KUAI1,4.**1Department of Biochemistry, Ministry of Education Key laboratory for Biodiversity Science and Ecological Engineering, school of Life sciences, Fudan university, 220 Handan Road, Shanghai 2004.3, China 2school of Horticulture and Gardening, Southwest {4. College, Kun Ming 650224. China 3Department of biology, school of Life and Environment Science, Shanghai Normal university, Shanghai 200234. China4.udan Centre for Genetic Diversity and designed Agriculture, Fudan university, 220 Handan Road, Shanghai 2004.3, China Department of Biochemistry Ministry of Education Key laboratory for Biodiversity Science and Ecological Engineering School of Life Sciences Fudan University 220 Handan Road Shanghai 200433 China.

A developmentally retarded mutant (drm1) was identified from ethyl methanesulfonate (EMS)-mutagenized M2 seedsin Columbia (Col-0) genetic background. The drm1 flowers 109 d after sowing, with a whole life cycle of about 160 *** also shows a pleiotropic phenotype, e.g., slow germination and lower germination rate, lower growth rate, curlingleaves and abnormal floral organs. The drm1 mutation was a single recessive nuclear mutation, which was mapped tothe bottom of chromosome 5 and located within a region of 20-30 kb around MXK3.1. There have been no mutantswith similar phenotypes reported in the literature, suggesting that DRM1 is a novel flowering promoting locus. Thefindings that the drm1 flowered lately under all photoperiod conditions and its late flowering phenotype was significantlyrestored by vernalization treatment suggest that the drm1 is a typical late flowering mutant and most likely associatedwith the autonomous flowering pathway. The conclusion was further confirmed by the revelation that the transcriptlevel of FLC was constantly upregulated in the drm1 at all the developmental phases examined, except for a very earlystage. Moreover, the transcript levels of two other important repressors, EMF and TFL1, were also upregulated in thedrm1, implying that the two repressors, along with FLC, seems to act in parallel pathways in the drm1 to regulateflowering as well as other aspects of floral development in a negatively additive way. This helps to explain why the drm1exhibits a much more severe late-flowering phenotype than most late-flowering mutants reported. It also implies that theDRM1 might act upstream of these repressors.

关键词： drm1 late-flowering autonomous flowering pathway Arabidopsis thaliana.

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Preliminary study on interaction between plant frictional root and rock-soil mass

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Science China(Technological sciences) 2010年第7期53卷 1938-1942页

作者： YAN ZhiXin1’2, SONG Yun3, JIANG Ping1’2 & WANG HouYu4.1 Key Laboratory of Mechanics on Disaster and Environment in Western China (Lanzhou university), Ministry of Education, Lanzhou 730000, China 2 school of Civil Engineering and Mechanics, Lanzhou university, Lanzhou 730000, China 3 College of Civil Engineering and Mechanics, Central South university of {4. and Technology, Changsha 4.0004. China 4.Air Force Engineering Design & Research Bureau, Beijing 100077, China 1. Key Laboratory of Mechanics on Disaster and Environment in Western China (Lanzhou university) Ministry of Education Lanzhou 730000 China2. School of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China3. College of Civil Engineering and Mechanics Central South University of Forestry and Technology Changsha 410004 China4. Air Force Engineering Design & Research Bureau Beijing 100077 China

The interaction between lateral root system of woody plant and soil mass is similar to the one between shrub, herbage and soil mass, and has the effect of frictional reinforcement on slope soil. It plays an important role in reinforcing soil strength in shallow slope. Therefore, slope soil mass can be considered as a composite of soil and plant roots and the soil strength and stability of shallow slope soil mass are improved. However, current researches still remain on the level of qualitatively analyzing the relation between root and soil mass. In this paper, some exploratory researches on quantitative analysis of the interaction mechanism between root and soil mass are conducted. With the study of interaction between herbage root system (lateral root system of woody plants) and soil mass, the mechanical model of interaction between frictional root and soil mass is established. The accuracy of the model is verified by field experiments of Pinus Yunnanensis. The mechanical model provides a crucial theoretical guidance to quantitatively analyzing the interaction between plant root and soil mass; it also has certain values in application.

关键词： plant slope protection vegetation for slope protection mechanical model frictional root

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Relationship Between Vegetation Restoration and Soil Microbial Characteristics in Degraded Karst Regions: A Case Study

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Pedosphere 2011年第1期21卷 132-138页

作者： WEI Yuan YU Li-Fei ZHANG Jin-Chi YU Yuan-Chun D. L. DEANGELIS school of Resources and Environmental Management Guizhou College of Finance and Economics Guiyang 550004 (China) College of forestry Guizhou University Guiyang 550025 (China) College of Forest and Environment Nanjing Forestry University Nanjing 210037 (China) Department of Biology University of Maimi P. O. Box 249118 Coral Gables FL 33124 (USA)

The mechanism of vegetation restoration on degraded karst regions has been a research focus of soil science and ecology for the last *** an attempt to preferably interpret the soil microbiological characteristic variation associated with vegetation restoration and further to explore the role of soil microbiology in vegetation restoration mechanism of degraded karst regions,we measured microbial biomass C and basal respiration in soils during vegetation restoration in Zhenfeng County of southwestern Guizhou Province,*** community level physiological profiles(CLPP) of the soil microbial community to were estimated determine if vegetation changes were accompanied by changes in functioning of soil microbial *** results showed that soil microbial biomass C and microbial quotient(microbial biomass C/organic C) tended to increase with vegetation restoration,being in the order arboreal community stage > shrubby community stage > herbaceous community stage > bare land *** trend was found in the change of basal respiration(BR).The metabolic quotient(the ratio of basal respiration to microbial biomass,qCO 2) decreased with vegetation restoration,and remained at a constantly low level in the arboreal community *** of the CLPP data indicated that vegetation restoration tended to result in higher average well color development,substrate richness,and functional *** utilization of specific substrate guilds was highest in the arboreal community *** component analysis of the CLPP data further indicated that the arboreal community stage was distinctly different from the other three *** conclusion,vegetation restoration improved soil microbial biomass C,respiration,and utilization of carbon sources,and decreased qCO 2,thus creating better soil conditions,which in turn could promote the restoration of vegetation on degraded karst regions.

关键词： basal respiratory community level physiological profile functional diversity metabolic quotient microbial biomass C

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