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chinese Science Bulletin 1999年第S2期44卷 125-126页

作者： BAI Zhanguo~(1,2. and WAN Guojiang~1 1. state key {2. of Environmental Geochemistry, Institute of Geochemistry, chinese academy of sciences, Guiyang 550002. china 2. state key {2. of Plant Nutrition Research of chinese Ministry of Agriculture Institute of soil and Fertilizer, chinese academy of Agricultural {12., Beijing 100081, china

WEST Yunnan and central Guizhou with variable altitudes and similar latitudes, located in the Yunnan-Guizhou Plateau of the eastern slope uplifting Himalayas, were selected as study areas in this note. Thetwo areas consist mainly of carbonate rocks discontinuously covered by similar soil types with severe soiland water loss except Lugu Lake catchment. Climate of the study areas is subtropical monsoon, apparently influenced by mingled southeastern monsoon and southwestern monsoon with abundant *** study is to comparatively describe distribution and inventory of 7Be and 137Cs in the sediments of Erhai Lake, Lugu Lake and Hongfeng Lake as well as in 2. surface soil profiles of their *** results have shown that: （i） In all the soil profiles, 7Be activities decrease exponentially with soil depth. 7Be apparent ac-

关键词： radionuclides soils sediments china.

Effect of Nitrogen on the Degradation of Cypermethrin and Its Metabolite 3-Phenoxybenzoic Acid in soil

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Pedosphere 2008年第5期18卷 638-644页

作者： XIE Wen-Jun ZHOU Jian-Min WANG Huo-Yan CHEN Xiao-Qin state key {2. of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Shandong key laboratory of Eco-Environmental Science for Yellow River Delta Binzhou University Binzhou 256603 （China）

Increasing use of pyrethroid insecticides has resulted in concerns regarding potential effects on human health and ecosystems. Cypermethrin and its metabolite 3-phenoxybenzoic acid(PBA) have exerted adverse biological impacts on the environment;therefore,it is critically important to develop different methods to enhance their degradation. In this study,incubation experiments were conducted using samples of an Aquic Inceptisol supplied with nitrogen(N) in the form of NH4NO3 at different levels to investigate the effect of nitrogen on the degradation of cypermethrin and PBA in soil. The results indicated that appropriate N application can promote the degradation of cypermethrin and PBA in soil. The maximum degradation rates were 80.0% for cypermethrin after 14 days of incubation in the treatment with N at a rate of 12..1 kg ha-1 and 41.0% for PBA after 60 days of incubation in the treatment with N at a rate of 182.7 kg ha-1. The corresponding rates in the treatments without nitrogen were 62.7% for cypermethrin and 2..8% for PBA. However,oversupplying N significantly reduced degradation of these compounds. Enhancement of degradation could be explained by the stimulation of microbial activity after the addition of N. In particular,dehydrogenase activities in the soil generally increased with the addition of N,except in the soil where N was applied at the highest level. The lower degradation rate measured in the treatment with an oversupply of N may be attributed to the microbial metabolism shifts induced by high N.

关键词： cypermethrin degradation nitrogen effect 3-phenoxybenzoic acid soil

Sulfur isotopic composition of Yellow and Yangtze rivers and uplift of the Qinghai-Xizang Plateau

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chinese Science Bulletin 1999年第S2期44卷 120-122页

作者： HONG Yetang, GU Ailiang, WANG Hongwei and HONG Bing state key {2. of Environmental Geochemistry, Institute of Geochemistry, chinese academy of sciences, Guiyang 550002. china state key {2. of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE sulfur isotopic composition of dissolved sulfate in any rivers has been recognized as a mixture of thesulfur derived from the soil, bedrock and the atmosphere. The measurement of the sulfur isotopic composition in a river water can provide background information on the biogeochemical cycling of sulfur in theriver basin. So far, however, little work has been done on sulfur isotope in the watersheds of the majorrivers of the world. In particular, no information of the sulfur isotope of the major rivers in Asian conti-

关键词： sulfur isotopic composition Yellow and Yangtze rivers uplift Qinghai-Xizang Plateau.

Dragload and Downdrag Performances of Inclined Pile Group Embedded in Consolidating soil

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Transactions of Tianjin University 2011年第3期17卷 175-180页

作者：孔纲强杨庆 key laboratory for Geomechanics and Embankment {2. of Ministry of Education Geotechnical Research Institute Hohai University state key {2. of Coastal and Offshore engineering Dalian University of Technology

The performance of inclined pile group embedded in consolidating soil under surcharge load was investigated by experiment in comparison with vertical pile group and single pile under the same conditions; dragload, downdrag, and layered soil settlement were measured. A three-dimensional numerical model was built via FLAC3D software, and verified by the experimental results. Influence factors, such as consolidation time, pile spacing, and pile tilt angle were analyzed. The results show that dragload of inclined pile group increases with the increase of consolidation time and pile spacing or the decrease of pile tilt angle. Downdrag of inclined pile group increases with the increase of consolidation time, pile spacing and pile tilt angle.

关键词： pile group negative skin friction consolidating soil downdrag dragload neutral plane

Wien Effect Characterization of Interactions Between Ions and Charged Sites on Clay Surfaces of Variable-Charge soils

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Pedosphere 2009年第5期19卷 545-553页

作者： ZHU Hao-Wen WANG Yu-Jun ZHOU Jun JIANG Jun LI Cheng-Bao ZHOU Dong-Mei S. P. FRIEDMAN key laboratory of {2. Environment and Pollution Remediation Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) state key {2. of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) Institute of soil Water and Environmental Sciences Agricultural Research Organization the Volcani Center Bet Dagan 50250 (Israel)

To investigate the interactions of oppositely charged sites on the surfaces of variable-charge soil particles with cations and anions, and to evaluate the mean Gibbs free binding and adsorption energies of various cations on particles of red soil and latosol, clay fractions smaller than 2.μm were separated from samples of the two variable-charge soils. Ferric oxides were removed from part of the clay fractions, which were then saturated with various chlorides （NaC1, KCl, CaCl2. CdCl2.or LaCl3）. Electrical conductivities （EC） of dilute suspensions of the original and of the iron oxides-free clay fractions in deionized water were measured with the SHP-2.short high-voltage pulse apparatus, which enables measurement of the Wien effect at field strengths （E） from 14 to 2.0 kV cm^-1. The Wien effect （EC-E） curves revealed EC increases of red soil suspensions between 14 and 2.0 kV cm^-1, of 8.3, 8.4, 12.1, 5.9, and 1.2.μS cm^-1 for NaCl, KCl, CaCl2. CdCl2. and LaCl3, respectively, reflecting the differing interactions with the various cations and chloride. The EC increments with the iron-free red soil suspensions were higher, being 2..7, 17.2. and 15.3 μS cm^-1 for NaCl, CaCl2. and CdCl2. respectively. In the natural latosol suspensions the EC increments were practically zero, whereas in the iron-free fractions there were significant EC increments of 10.3, 5.7, 5.0, and 1.6μS cm^-1 for NaCl, CaCl2. CdCl2. and LaCl3, respectively.

关键词： electrical conductivity field strength iron oxide overlapping ζ potential

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 {2. of Remote Sensing Science, Institute of Remote Sensing Applications, chinese academy 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 academy of sciences, Beijing 100039, china 4. Department of Atmospheric Physics, Peking University, Beijing 100871, china state key {2. of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University Beijing 100875 China Graduate University Chinese Academy of Sciences Beijing 100039 China Department of Atmospheric Physics Peking University Beijing 100871 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.

Mineral Coated Fertilizer Effect on Nitrogen-Use Efficiency and Yield of Wheat

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Pedosphere 2005年第4期15卷 526-531页

作者： LI Jian-Yun HUA Quan-Xian TAN Jin-Fang ZHOU Jian-Min HOU Yan-Lin L Department of soil Environmental Science Research Center for Eco-Environmental Science Chinese Academy of Sciences Beijing 100085 （China）. state key {2. of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate School of the chinese academy of sciences Beijing 100039 （China） College of Agriculture Henan Agricultural University Zhengzhou 450002 （China）

A field experiment with winter wheat （Triticum aestivurn L.） was conducted on a silt loam calcaric endorusti-ustic Cambosols derived from the Yellow River alluvial deposits in Henan, china, from 2.01 to 2.02.to evaluate N recovery and agronomic performance of different mineral coated fertilizers （MiCFs） compared to normal urea used in wheat cropping systems under field conditions. Five treatments, including CK （check, no N fertilizer）, urea and three different MiCFs at an equivalent N application rate were established in a randomized complete block design. N release from MiCFs in soil was more synchronous with the N requirement of wheat throughout the growth stages than that from urea, with grain yield of the MiCF treatments significantly higher （P 〈 0.05） than that of the treatment urea. Correspondingly, the N recovery rate was greater for all MiCFs compared to urea, increasing from 32.8% up to 50.1%. Due to its high recovery and low cost, use of the mineral coated N fertilizers was recommended instead of the polymer coated N fertilizers.

关键词： mineral coated fertilizer N recovery urea winter wheat

Simulation of dam breach development for emergency treatment of the Tangjiashan Quake Lake in china

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Science china(Technological sciences) 2008年第S2期51卷 82-94页

作者： WANG GuangQian,LIU Fan,FU XuDong & LI TieJian state key {2. of Hydroscience and engineering,Tsinghua University,Beijing 100084,china state key {2. of Hydroscience and engineering Tsinghua University Beijing China

The Tangjiashan Quake Lake is the largest quake lake triggered by the 5.12.Wenchuan Earthquake that happened on May 12.2.08 in china,posing high risk of catastrophic flash flood hazards to downstream human life and properties.A physics-based numerical simulation approach is proposed for real-time prediction of dam breach development of the Tangjiashan Quake Lake in the case of emergency *** erosion and lateral development of the dam breach are represented through accounting for the underlying physics including selective sediment transport and gravitational *** breach erosion model that involves few parameters enables quick calibration based on the monitored hydrological data in emergency analysis where fully geotechnical information about the barrier dam is not *** process of dam breach development is found to be nonlinear in cascades due to the combined effects of headcutting and bank *** agreement between the simulation results and the observed data shows the applicability of the present approach for emergency analysis of quake *** will arise in the situation where the soil composition of barrier dam is significantly *** of circular arc failure for cohesive soil and lateral seepage in bank slope will also enhance its applicability to complex situations.

关键词： quake lake earthquake dam breach simulation numerical model erosion collapse headcutting

Permafrost on the Qinghai-tibet Plateau under a Changing Climate

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chinese Science Bulletin 1999年第S1期44卷 152-158页

作者： JIN Huijun CHENG Guodong LI Xin LI Shuxun Observatory and Research Station of the Qinghai-Tibet Plateau. state key {2. of frozen soil engineering, LIGG, CAS, lanzhou 730000 china.

Permafrost on the Qinghai-Tibet Plateau (QTP) has experienced major shifts during theQuaternary. During the past 40 years, permafrost has been degrading extensively, due to climaticwarming. Simulations suggest significant degradation of permafrost both in extent and inthickness within the next 50-100 years. Freshwater wetlands on the QTP can contributesignificantly to the global budgets in the atmospheric greenhouse gases. Permafrost degradationon the QTP has caused destabilization of foundations of engineering structures, deterioration ofgrasslands and meadows, and weakening of permafrost control on water resources.

关键词： Permafrost Active layer Climatic changes Greenhouse gases Environmental impacts

Vertical　fluxes　of　volatile　mercury　over　soil　surfaces　in　Guizhou　Province,china

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Journal of Environmental sciences 1997年第2期9卷 116-120页

作者： Feng Xinbin, Chen Yecai, Zhu Weiguo state key {2. of Environmental Geochemistry, Institute of Geochemistry, chinese academy of sciences, Guiyang 550002. china

An instrument that can be used to measure the fluxes of volatile mercury over soil surface in field was set up. From August to October in 1993, the fluxes of volatile mercury over soil surfaces at 5 sites of three different areas(high mercury area, mercury polluted area, and reference area) were measured. The results showed that the measured fluxes over soil surface during daytime were higher than those measured at night, and that the flux of volatile mercury over soil surface has relationship with both the total mercury contents of soil and air temperature.

关键词： mercury fluxes flux chamber Guizhou Province Danzhai Mercury Mine.