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Estimating surface evapotranspiration using combined MODIS and CBERS-02.data

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science china(Technological sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2. LIU Qinhuo1, TANG Yong1,3. TIAN Guoliang1, GU Xingfa1, LI Xiaowen1,2. ZHENG Hongsheng4 & CHEN Jiayi4 1. State Key Laboratory of Remote Sensing science, {2. of Remote Sensing Applications, chinese {3. of sciences, Beijing 100101, china 2. Research Center for Remote Sensing and GIS, Department of Geography, Beijing Normal University, Beijing 100875, china 3. Graduate University of chinese {3. of sciences, Beijing 10003., china 4. Department of Atmospheric Physics, Peking University, Beijing 100871, china 1. State Key Laboratory of Remote Sensing science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China3. Graduate University of Chinese Academy of Sciences 100039 Beijing China4. Department of Atmospheric Physics Peking University 100871 Beijing China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02.data were used to produce land use class of Baiyangdian area, Hebei Province, china in the autumn of 2.04. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

Distribution characteristics of magnetic susceptibility of the surface sediments in the southern Yellow Sea

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chinese science Bulletin 2003年第B06期48卷 37-41页

作者： GE Shulan~(1,2.3., SHI Xuefa~1 & HAN Yibing~1 1. Key Laboratory of Marine Sedimentology and Environmental Geology, First institute of Oceanography, State Oceanic Administration. Qingdao 2.6061.{2. 2. institute of Geology and Geophysics, {3. academy of sciences, Beijing 10002..{2. 3. Graduate School. {3. academy of sciences, Beijing 10003..{2. 1. Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 3. Graduate School Chinese Academy of Sciences 100039 Beijing China

The characteristic distributions of magnetic susceptibility (MS) are analyzed on the basis of susceptibility of 172.surface sediment samples in the southern Yellow Sea (SYS). The preliminary results are as follows: first, the distributions clearly correspond to different modern sediment assemblages in the continental sea, which indicates different sediment origins. With the 3. μCGS isoline being taken as demarcation line, the study area can then be divided into section H (high MS value area) and section L (low MS value area). Section H is mainly adjacent to land with two main sources of the Changjiang River and the Huanghe *** L is mainly an eddy sediment area, where Yellow Sea Cold Water is entrenched all the year round. The distribution pattern of MS could tell apart strong or weak hydrodynamic conditions and has a close relation to the circulation system in this area. At the areas of the SYS Circumfluent and northern East china Sea (NECS) Circumfluent (weak hydrodynamic), the MS has low values, while in the areas of Coastal Current (strong hydrodynamic), the values are *** the same time, the oxidizing areas tend to take on higher MS, while the reducing areas have lower one. It seems safe to say that the MS in the continental sea reflects more of the sediment origin and sedimentary environment, which is different from that of loess, lake and surface {2. as a climate proxy.

关键词：中国黄海表面沉积物磁化率等值线长江黄河旋涡沉积区循环系统

Rock-weathering by lichens in Antarctic: patterns and mechanisms

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Journal of Geographical sciences 2002年第4期12卷 387-396页

作者： CHEN Jie1, Hans-Peter Blume2.1. institute of soil {2., CAS,{3., china 2. institute of Plant Nutrition and soil {2., University of Kiel, D-2.098 Kiel, Germany) institute of soil {2. CAS Nanjing 210008 institute of Plant Nutrition and soil {2. University of Kiel 德国 Kiel

Saxicolous species of lichens are able to induce and accelerate weathering of their rock substrate, and effects of lichens on substrate can be attributed to both physical and chemical causes. This paper is focused on biotic weathering actions of epilithic and endolithic species on the different rock types (sandstones and volcanogenic rocks) in Antarctica. The patterns, mechanisms, processes and neoformations of rock-weathering resulting from lichen colonization are expounded in detail. Furthermore, it is pointed out that, for a better understanding of the impacts of lichens on environments, the studies on the rate of biotic weathering and the comprehensive involvement of the lichen effects on weathering of natural rocks remain to be carried out in Antarctica.

关键词： lichen rock-weathering lichen-rock interface biogenic minerals Antarctic

soil Erosion Changes over the Past Five Decades in the Red soil Region of Southern{2.

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Journal of Mountain science 2010年第1期7卷 92-99页

作者： LIANG Yin LI Decheng LU Xixi YANG Xuan PAN Xianzhang MU Huan SHI Deming ZHANG Bin institute oj: soil {2. Chinese Academy of Sciences Nanjing 210008 China Department of Geography National University of Singapore Singapore 119260 Key Laboratory of soil Environment and Pollution Remediation Institute of Soil Science Chinese Academy of Sciences. Nanjing 210008 China

This paper reports the dynamic changes of soil and water loss in the red soil region of Southern{2. since the 1950s. The red soil region covers eight provinces: Jiangxi, Zhejiang, Fujian, Anhui, Hubei, Hunan, Guangdong and Hainan. From the 1950s to 1986, the annual rate of soil erosion increased by 3.4%. From 1986 to 1996 and from 1996 to 2.00, the annual rates of soil erosion decreased by 2.0% and 0.3.%, respectively. Field surveys showed that from 2.00 to 2.05, the area of soil and water loss decreased annually by 1.2.. This decrease was a result of large-scale erosion control activities across{2.. Although the eroded soil has been restored, the restoration process is very slow and full restoration will take a long time. Our report suggests that controlling soil and water loss is a challenging task, and additional measures must be taken to effectively control the soil erosion in the red soil region.

关键词： red soil region soil and water loss dynamic change remote sensing field samplingsurvey

A SIMPLIFIED NUMERICAL MODEL OF 3.D GROUNDWATER AND SOLUTE TRANSPORT AT LARGE SCALE AREA

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Journal of Hydrodynamics 2010年第3期22卷 319-328页

作者： LIN Lin YANG Jin-Zhong ZHANG Bin ZHU Yan State Key Laboratory of Water Resources and Hydropower Engineering Wuhan University Wuhan 430072China institute of soil {2. Chinese Academy of Sciences Nanjing 210008 China

A simplified numerical model of groundwater and solute transport is developed. At large scale area there exists a big spatial scale difference between horizontal and vertical length scales. In the resultant model, the seepage region is particularly divided into several virtual layers along the z direction and vertical 1-D columns covering x-y 2.D area according to stratum properties. The numerical algorithm is replacing the full 3.D water and mass balance analysis as the 2.D Galerkin finite element method in x- and y-directions and 1-D finite differential approach in the z direction. The reasonable method of giving minimum thickness is successfully used to handle transient change of water table, drying cells and problem of rewetting. The solution of the simplified model is preconditioned conjugate gradient and ORTHOMIN method. The validity of the developed 3.D groundwater model is tested with the typical pumping and backwater scenarios. Results of water balance of the computed example reveal the model computation reliability. Based on a representative 3.D pollution case, the solute transport module is tested against computing results using the MT3.MS. The capability and high efficiency to predict non-stationary situations of free groundwater surface and solute plume in regional scale problem is quantitatively investigated. It is shown that the proposed model is computationally effective.

关键词： groundwater movement solute transport simplified model 3.D mass balance numerical simulation

Atmospheric Sulfur Deposition on Farmland in East china

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Pedosphere 2005年第1期15卷 120-128页

作者： WANGTi-Jian YANGHao-Ming GAOLi-Jie ZHANGYan HUZheng-Yi XUCheng-Kai DepartmentofAtmosphericscience NanjingUniversityNanjing210093China DepartmentofAtmosphericscience NanjingUniversityNanjing210093China／／KeyLaboratoryofMeteorologicalDisasterandEnvironmentalVariationNanjingInstituteofMeteorologyNanjing210044China StateKeyLaboratoryofsoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofScienceNanjing210008China

Atmospheric sulfur deposition onto typical farmland in East china was investigated using both field measurements and numerical modeling. The field measurements were conducted at the Experiment Station of Red soil Ecology, {2. {3. of sciences, 10 km from Yingtan, Jiangxi Province, East china, between November 1998 and October 1999, and at the Changshu Ecological Experiment Station, {2. {3. of sciences, in a rapidly developing region of Jiangsu Province, East china, between April 2.01 and Marc…

关键词： atmospheric sulfur deposition East china farmland

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 {2.s and Natural Resources Re-search, chinese {3. of {2.s, Beijing 100101, china 2. institute of Forestry, chinese {3. of Forestry {2.s, Beijing 100091, china 3. Department of Civil Engineering, University of Hong Kong, Hong Kong, china 4. Eco-environmental Research Center, chinese {3. of {2.s, Beijing 100085, china 5. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716, 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 53. 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 {2. 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 3.%.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.

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 Geography and Limnology 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

Pedodiversity: a controversial concept

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Journal of Geographical sciences 2001年第1期11卷 110-116页

作者： CHEN Jie1, ZHANG Xue-lei1, GONG Zi-tong1, WANG Jun2.(1. institute of soil {2., CAS,{3., china 2. Surveying and Mapping Bureau of Jiangsu Province,{3., china) institute of soil {2. CAS Nanjing China Surveying and Mapping Bureau of Jiangsu Province Nanjing China

The concept of pedodiversity and its measurement methodology proposed and developed by Ibá?ez research term is introduced. An attempt to apply pedodiversity to analyze spatial soil variation and distribution patterns on the global scale is briefly demonstrated. Furthermore, constructive comments and criticisms on pedodiversity and its measurement from the noted pedologists and ecologists are outlined. Finally, potential applications of pedodiversity in soil {2. and other relevant disciplines are discussed.

关键词： pedodiversity soil global distribution spatial variation species richness species evenness Shannon Index