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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

Wuhan University Journal of Natural Sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3.,HUANG Zhiqin 2. 3. 4 1. The Faculty of {2. and Resources Science, Sichuan Normal University, Chengdu 610066, Sichuan, china 2. institute of Mountain Hazards and Environment, {3. academy of Sciences, Chengdu 610041, Sichuan, china 3. Graduate University of the {3. academy of Sciences, Beijing 100049, china 4. Information Center of Land and Resources Department of Sichuan Province, Chengdu 610041, Sichuan, china The Faculty of geography and Resources Science Sichuan Normal University Chengdu Sichuan China institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate University of the chinese academy of Sciences Beijing China Information Center of Land and Resources Department of Sichuan Province Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 3.°. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

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Effect of CO_2.Enrichment on the Growth and Nutrient Uptake of Tomato Seedlings

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Pedosphere 2007年第3期17卷 343-351页

作者： LI Juan ZHOU Jian-Min DUAN Zeng-Qiang DU Chang-Wen WANG Huo-Yan State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 （China） nanjing institute of {2. and {3. Chinese Academy of Sciences Nanjing 210008 （China）

Exposing tomato seedlings to elevated CO2.concentrations may have potentially profound impacts on the tomato yield and quality. A growth chamber experiment was designed to estimate how different nutrient concentrations influenced the effect of elevated CO2.on the growth and nutrient uptake of tomato seedlings. Tomato (Hezuo 906) was grown in pots placed in controlled growth chambers and was subjected to ambient or elevated CO2.(3.0 or 72.μL L-1) and four nutrient solutions of different strengths (1/2., 1/4-, 1/8-, and 1/16-strength Japan Yamazaki nutrient solutions) in a completely randomized design. The results indicated that some agricultural characteristics of the tomato seedlings such as the plant height, stem thickness, total dry and fresh weights of the leaves, stems and roots, the G value (G value = total plant dry weight/seedling age), and the seedling vigor index (seedling vigor index = stem thickness/(plant height×total plant dry weight) increased with the elevated CO2. and the increases were strongly dependent on the nutrient solution concentrations, being greater with higher nutrient solution concentrations. The elevated CO2.did not alter the ratio of root to shoot. The total N, P, K, and C absorbed from all the solutions except P in the 1/8- and 1/16-strength nutrient solutions increased in the elevated CO2.treatment. These results demonstrate that the nutrient demands of the tomato seedlings increased at elevated CO2.concentrations.

关键词： CO2.enrichment nutrient strength nutrient uptake tomato seedlings

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A generalized mean shift tracking algorithm

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Science china(Information Sciences) 2011年第11期54卷 2373-2385页

作者： CHEN JianJun 1,4,ZHANG SuoFei 1,AN GuoCheng 2.& WU ZhenYang 1,3. School of Information Science and Engineering,Southeast University,nanjing 2.0096,{2. 2.Intelligence Engineering Lab,institute of Software {3. academy of Sciences,Beijing 100190,{2. 3.Key Laboratory of Underwater Acoustic Signal Processing of Ministry of Education,Southeast University,nanjing 2.0096,{2. 4 nanjing Research institute of Electronic Technology,nanjing 2.0013.{2. School of Information Science and Engineering Southeast University Nanjing China nanjing Research institute of Electronic Technology Nanjing China Intelligence Engineering Lab Institute of Software Chinese Academy of Sciences Beijing China Key Laboratory of Underwater Acoustic Signal Processing of Ministry of Education Southeast University Nanjing China

CAMSHIFT algorithm and Comaniciu/Meer algorithm are two fundamental frameworks of mean shift procedure for video target *** paper generalizes the two well-known mean shift tracking algorithms,originally due to Bradski and Comaniciu/Meer.A new general similarity function which defines the distance between the target model and target candidate is employed to calculate the pixel weights and the target *** target size is iteratively estimated and updated based on the zeroth order moment of the pixel *** we prove that both the CAMSHIFT algorithm and the Comaniciu/Meer algorithm can be included in the generalized mean shift tracking *** tracking performances of three mean shift algorithms in the unified framework are shown and compared in the experimental results.

关键词： mean shift CAMSHIFT video target tracking similarity measure

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Soil Organic Carbon Storage in china

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Pedosphere 2004年第4期14卷 491-500页

作者： XIEXian-Li SUNBo ZHOUHui-Zhen LIAn-Bo instituteofSoilScience ChineseAcademyofSciencesNanjing210008（China）. geographyCollege NanjingNormalUniversityNanjing210097（China）

Soil organic carbon (SOC) storage under different types of vegetations in china were estimated using measured data of 2.440 soil profiles to compare SOC density distribution between different estimates, to map the soil organic carbon stocks under different types of vegetation in china, and to analyze the relationships between soil organic carbon stocks and environmental variables using stepwise regression analyses. Soil organic carbon storage in china was estimated at 69.3. Gt (10 15 g). There was a big difference in SOC densities for various vegetation types, with SOC distribution closely related to climatic patterns in general. Stepwise regression analyses of SOC against environmental variables showed that SOC generally increased with increasing precipitation and elevation, while it decreased with increasing ***, the important factor controlling SOC accumulation for forests was elevation, while for temperate steppes mean annual temperature dominated. The more specific the vegetation type used in the regression analysis, the greater was the effect of environmental variables on SOC. However, compared to native vegetation, cultivation activities in the croplands reduced the influence of environmental variables on SOC.

关键词： china environmental factors soil organic carbon storage vegetation

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Some Fertility Characteristics and Fertilizer Requirements of a Newly Reclaimed Upland Red Soil Derived from Quaternary Red Clay

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Pedosphere 2000年第4期10卷 373-382页

作者： MA MAOTONG and XIE JIANCHANG (institute of Soil Science, the chinese {2. of Sciences,{3. china) 中科院南京土壤所江苏南京 210008

A series of field experiments from 1990 to 1994 in Yingtan, Jiangxi Province, were conducted on an upland red soil derived from Quaternary red clay which had been reclaimed three years before the experiments, in order to study the fertility characteristics and fertilizer requirements of the newly reclaimed soil. The field experiments included that on nutrient characteristics and fertilizer effect, that on K-supplying potential and K-Mg relationship, that on fertilization rates of K and N, etc. The newly reclaimed upland soil was low in both N and P, and its responses to nitrogen and phosphate application were very significant. The K-supplying potential was also low, so the soil was highly responsive to K fertilizer. The effect of Ca and Mg fertilizers was not so great for the reason that certain amounts of Ca and Mg were incorporated into the soil through application of calcium magnesium phosphate during land leveling before the experiments. Among the four micronutrients, B, Mo, Zn and Cu, B had the greatest effect on the soil. The fertilizer requirements of the soil were in an order of P and N > K > lime and B > Mg > Mo, Zn and Cu. Eight crops tested had different fertilizer-requiring characteristics. Rapeseed was very sensitive to P and B fertilizers. Barely was especially sensitive to P and lime and it also responded to B, Mo, Zn and Cu. And sweet potato was especially sensitive to K.

关键词： fertility characteristics fertilizer requirement newly reclaimed upland soil

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Impact Assessment and Protection of Outstanding Landscape Integrity in a Natural Heritage Site:Fairy Valley,Kanas Nature Reserve,Xinjiang,china

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Journal of Mountain Science 2011年第1期8卷 46-52页

作者： HAN Fang1,2.YANG Zhaoping1,LIU Xinyu1,2.DI Feng3.1 Xinjiang institute of Ecology and {2.,chinese {3. of Sciences,Urumqi 83.011,china 2.Graduate University of chinese {3. of Sciences,Beijing 100049,china 3.Xinjiang Department of Science and Technology,Urumqi 83.011,china Xinjiang institute of Ecology and geography Chinese Academy of Sciences Urumqi China Graduate University of chinese academy of Sciences Beijing China Xinjiang Department of Science and Technology Urumqi China

The essential purpose of the Convention Concerning the Protection of World Cultural and Natural Heritage is to protect the integrity of heritage *** landscape is the core embodiment of the aesthetic value of a natural heritage *** paper proposes a new assessment method from the point of view of the protection of heritage *** is used to measure the degree of outstanding landscape integrity under the human and natural impact in natural heritage *** paper employ three indices,a visual index of outstanding landscape,a harmony index of the artificial landscape and a disturbance index of damaged landscape,to measure the impact of landscape *** impact assessment model is based on a weighted combination of the three *** study site is the Fairy Valley,Kanas Nature Reserve,Xinjiang Uygur Autonomous Region in northwest *** information employed is derived from field investigation and a Digital Elevation Model(DEM).A comprehensive evaluation of the Fairy valley was undertaken and it was determined that the outstanding landscape values are being *** protection methods are proposed to reduce the adverse effects and maintain landscape quality,thereby providing site managers with suggestions for the protection of natural heritage *** broadly,the paper contributes novel methods of landscape assessment applicable to natural protected areas.

关键词： Landscape integrity Landscape impact assessment Landscape protection Natural heritage site Kanas Nature Reserve Xinjiang

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Criteria for defining and recognizing the various orders of sequences in outcrop sequence stratigraphy

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Science china Earth Sciences 2004年第7期47卷 618-629页

作者： WANG Xunlian Faculty of Earth Sciences and Mineral Resources, china University of Geosciences, Beijing 100083. china State Key Laboratory of Palaeobiology and Stratigraphy, nanjing {3. of Geology and Palaeontology, chinese academy of Sciences, nanjing 2.0008, china Faculty of Earth Sciences and Mineral Resources China University of Geosciences Beijing China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

The regional distribution in different depositional facies belts is here regarded as an important criterion for defining and recognizing the various orders of sequences. The third-order sequence is possibly global in nature, which may be discerned in different depositional facies belts in one continental margin and can be correlated over long distances, sometimes even worldwide. Commonly, correlation of subsequence (fourth-order sequence with time interval of 0.51.5 Ma) is difficult in different facies belts, although some of them may also be worldwide in distribution. A subsequence should be able to discern and correlate within at least one facies belt. The higher-order sequences, including microsequence (fifth-order sequence) and minisequence (sixth-order sequence), are regional or local in distribution. They may reflect the longer and shorter Milankovitch cycles respectively. Sequence and subsequence are usually recognizable in different facies belts, while microsequence and minisequence may be distinguished only in shallow marine deposits, but not in slope and basin facies deposits. A brief discussion is made on the essential conditions for correct identification of sequences, useful methods of study, and problems meriting special attention in outcrop sequence stratigraphy.

关键词： outcrop sequence stratigraphy, facies belt, sequence, subsequence, microsequence, minisequence, meter-scale cyclothem, Milankovitch cycle.

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Structural properties of GaN(0001) epitaxial layers revealed by high resolution X-ray diffraction

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Science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 68-71页

作者： XIE ZiLi 1,2.3. ZHOU YuanJun 1 , SONG LiHong 1,2., LIU Bin 1 , HUA XueMei 1,2., Xiu XiangQian 1 , ZHANG Rong 1,2.3.& ZHENG YouDou 1,2.3.1 JiangSu Provincial Key Laboratory of Advanced Photonic and Electronic Materials and Department of Physics, nanjing University, nanjing 2.0093. china 2.nanjing National Laboratory of Microstructures, nanjing 2.0093. china 3.NJU-Yangzhou {12. of Opto-electronics, Yangzhou, 2.5001, china JiangSu Provincial Key Laboratory of Advanced Photonic and Electronic Materials and Department of Physics Nanjing University Nanjing China nanjing National Laboratory of Microstructures Nanjing China NJU-Yangzhou institute of Opto-electronics Yangzhou China

High-resolution X-ray diffraction has been used to analyze GaN(0001) epitaxial layers on sapphire substrates. Several structural properties of GaN, including the lattice constants, strains, and dislocation densities are revealed by the technique of X-ray dffraction (XRD). Lattice constants calculated from the omega/2.heta scan are c=0.5185 nm and a=0.3.57 nm. Also, the in-plane strain is -1.003., while out of the plane, the epitaxial film is almost relaxed. Several methods are used to deduce the mosaicity and dislocation density of GaN, showing that the edge type dislocations are the overwhelming majority.

关键词： GaN XRD dislocation epitaxial

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Palaeogene fossil Populus leaves from Lanzhou Basin and their palaeoclimatic significance

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chinese Science Bulletin 2004年第14期49卷 1494-1501页

作者： SUN Bainian1,2. YAN Defei1, XIE Sanping1, CONG Peiyun1, XIN Cunlin1 & YUN Fei1 1. Key Laboratory of Western china抯 Environmental Systems of the Ministry of Education, Lanzhou University, Lanzhou 73.000, china 2. State Key Laboratory of Palaeobiology and Stratigraphy, nanjing {3. of Geology and Palaeontology, chinese academy of Sci-ences, nanjing 2.0008, china Key Laboratory of Western china’s Environmental Systems of the Ministry of Education Lanzhou University Lanzhou China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

An angiosperm compression flora is found in Palaeogene from Lanzhou Basin and the cuticular analysis of Populus davidiana Dode in the flora is carefully made. Fur-thermore, the fossil cuticles are compared with the epidermal structures of extant Populus leaves growing in different en-vironments, i.e. moist, semimoist, and semiarid to arid cli-matic regions. The present experiments indicate that mature leaves of P. davidiana show leaf size from big to small, leaf cuticles from thick to thin and anticlinal walls of epidermal cells from faintness to clarity along with the increase of lati-tudes of the plant distributions, the climatic variation from moist to arid, the annual precipitation from more to less and the annual mean temperature from high to low. The fossil P. davidiana differs from the specimens collected from Shandan in semiarid to arid climatic regions but closely resembles the Wushan leaves in a semi-moist climatic area in a lot of fea-tures. In a word, the new research may reflect that the flora lives in a semi-moist climatic environment. The present dis-covery of compression of Paleogene Populus davidiana is of great significance to studying vegetation types, climatic and environmental changes during the primal uplifting of the Qinghai-Tibet Plateau.

关键词：古气候兰州盆地山杨化石角质层早第三纪被子植物

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Ecological response to the climate change on the northern slope of the Tianshan Mountains in Xinjiang

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Science china Earth Sciences 2005年第6期48卷 765-777页

作者： CHEN Xi1, LUO Geping1, XIA Jun2. ZHOU Kefa1, LOU Shaoping3.& YE Minquan4 1. Xinjiang institute of Ecology and {2., chinese {3. of Sciences, Urumqi 83.011, china 2. institute of Geographical and Resources Sciences, chinese {3. of Sciences, Beijing 100101, china 3. Urumqi Meteorological-satellite Land Station, Urumqi 83.011, china 4. Seismological Bureau of Xinjiang Uygur Autonomous Region, Urümqi 83.011, china Correspondence should be addressed to Chen Xi Xinjiang institute of Ecology and geography Chinese Academy of Sciences Urumqi China institute of Geographical and Resources Sciences Chinese Academy of Sciences Beijing China Urumqi Meteorological-satellite Land Station Urumqi China Seismological Bureau of Xinjiang Uygur Autonomous Region Urümqi China

The Tianshan Mountains is a high and huge mountain body lying across the central part of Xinjiang, china, and is also the main area where the runoff forms in Xinjiang. In this paper, a set of RS-based study methods is put forward for deriving the information about the natural change of the ecology in arid areas, and the relationship between the climate change trend and the corresponding ecological response on the northern slope of the Tianshan Mountains since recent 40 years is analyzed from the scales of the land cover ecosystems and landscapes based on the observed data of climate, hydrology, modern glaciers and lakes on the northern slopes of the Tianshan Mountains since recent 40 years and the satellite RS data since recent 10 years by using the RS and GIS technologies. The results are as follows: (1) The overall trend of climate change on the northern slope of the Tianshan Mountains since recent 40 years is that both air temperature and precipitation are increased, especially the increase amplitudes of air tempera-ture, precipitation and annual runoff volume are high since the decade of the 1990s; (2. the in-tegrated indexes of the vegetation in all the geographical divisions on the northern slope of the Tianshan Mountains are obviously increased since recent 10 years, especially in the artificial oases and the foothill belts, such a change trend is advantageous for improving the vegetation ecology; and (3. the vegetation ecology in the arid areas is extremely sensitive to the climate change, the vegetation coverage and the biomass on the northern slope of the Tianshan Moun-tains are continuously increased because of the climate change since recent 10 years, their in-crease amplitudes in the plains and during the late stage are obviously higher than that in the mountainous regions and during the early stage.

关键词： north slope of the Tianshan Mountains, climate change, hydrological change, natural change of ecology,RS and GIS, vegetation index.

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