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Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in Beijing, china

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Science china earth {2. 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2.1. Institute of Geographical sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101,{2. 2. Laboratory for earth surface processes, peking university, Beijing 100871,{2. 1. Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for earth surface {2. Peking University 100871 Beijing China

Taking Beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952.2.03.were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952.1983. the average input and output amount of HCHs through agricultural application and degradation are 13. t and 150 t respectively. The dominant transfer {3. of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these {3. are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92. of total transfer fluxes of HCHs isomers. There were approximately 2.3. HCHs in all {2. compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983. and this percentage may descend to 0.5% after 2. years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

Adjoint method for the optimum planning of industrial pollutant sources

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Science china earth {2. 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2. HU Fei2.& ZHU Jiang2.1. {3. of environmental {2., peking university, Beijing 100871, china 2. LAPC, Institute of Atmospheric Physics, Chinese Academy of {2., Beijing 10002., china 1. college of environmental {2. Peking University 100871 Beijing China 2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

Size-dependent hydroxyl radicals generation induced by SiO_2.ultra-fine particles: The role of surface iron

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Science china Chemistry 2009年第7期52卷 1033-1041页

作者： SHANG Yu1, ZHU Tong1, LI Yi1,2.& ZHAO JinCai3.1 college of environmental {2. and Engineering, peking university, Beijing 100871, china 2.Chinese Academy of Meteorological {2., Beijing 100871, china 3.Institute of Chemistry, Chinese Academy of {2., Beijing 100871, china 1. college of environmental {2. and Engineering Peking University Beijing 100871 China 2. Chinese Academy of Meteorological sciences Beijing 100871 China 3. Institute of Chemistry Chinese Academy of Sciences Beijing 100871 China

Oxidative stress and hydroxyl radicals (·OH) play important roles in adverse health effects caused by inhalable ambient air particles (PM10). The ultra-fine fraction of PM10 has been hypothesized as one of the critical contributors to ·OH generation. Both in vivo and in vitro studies have shown that ultra-fine particles (UFPs) or nano-particles generate more ·OH than larger particles with identical mass and composition. Both the surface area and surface-adsorbed redox-active metals have been suggested as factors to determine the oxidative capacity of UFPs. In this study, the ·OH-generating capability of dif-ferent sizes of SiO2.particles was investigated in order to determine which factor influences particle-induced ·OH generation. The amount of ·OH generated in both acellular and cellular systems was quantified using a capillary electrophoresis method following exposure to SiO2.particles with diameters of 14, 100, and 500 nm. The amount of ·OH was strongly dependent on particle size, and a significant enhancement was observed only with 14 nm particles. Further studies indicated a close association between ·OH and iron ion concentration (R2.= 0.812. psurface iron being removed, did not generate ·OH. The iron-containing leachate from these washings was able to enhance ·OH production as untreated particles did. Therefore, the presence of adsorbed iron on the surface of the SiO2.particles is presented as a possible mechanism of UPFs-induced ·OH generation. The SiO2.acted as an inert substrate, and the surface of ultra-fine SiO2.particles acted as a carrier for iron.

关键词： ultra-fine particles nano-particles ·OH oxidative stress size-effect

Contribution of Root and Microbial Respiration to Soil CO_2.Efflux and Their environmental Controls in a Humid Temperate Grassland of Japan

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Pedosphere 2009年第1期19卷 31-39页

作者： WANG Wei FENG Jiang T. OIKAWA Department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 （China） School of Urban and environmental sciences Northeast Normal University Changchun 130024 （China） Institute of Biological sciences University of Tsukuba Tsukuba Ibaraki 305-8572 （Japan）

Soil CO2.efflux, root mass, and root production were investigated in a humid temperate grassland of Japan over a growing season （Apr. to Sep.） of 2.05 to reveal seasonal changes of soil CO2.efflux, to separate the respective contributions of root and microbial respiration to the total soil CO2.efttux, and to determine the environmental factors that control soil respiration. Minimal microbial respiration rate was estimated based on the linear regression equations between soil CO2.effiux and root mass at different experimental sites. Soil CO2.efflux, ranging from 4.99 to 16.2. μmol CO2.m^-2.s^-1, depended on the seasonal changes in soil temperature. The root mass at 0-10 cm soil depth was 0.82.and 1.2. kg m^-2.in Apr. and Sep., respectively. The root mass at 0-10 cm soil depth comprised 60% of the total root mass at 0-50 cm soil depth. The root productivity at 0-3. cm depth varied from 8 to 180 g m^-2.month^-1. Microbial and root respiration rates ranged from 1.3. to 5.51 and 2.72.to 12.06μmol CO2.m^-2.s^-1, respectively. The contribution of root respiration to the total soil CO2.efflux averaged 53., ranging from 3.% to 72.. The microbial respiration rate was exponentially related to soil temperature at 10 cm depth （R^2.= 0.9400, P = 0.002. n = 6）, and the root respiration rate was linearly related to the root production at 0-3. cm depth （R2.= 0.6561, P = 0.042. n = 6）.

关键词： grasslands microbial respiration root production root respiration

Variations in carbon isotope ratios of C_3.plants and distribution of C_4 plants along an altitudinal transect on the eastern slope of Mount Gongga

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Science china earth {2. 2009年第10期52卷 1714-1723页

作者： LI JiaZhu1, WANG GuoAn2. LIU XianZhao1, HAN JiaMao3. LIU Min4 & LIU XiaoJuan2.1 college of Geography and Planning, Ludong {3., Yantai 2.402.,{2. 2.Key Laboratory of Plant-Soil Interactions, Ministry of Education, college of Resources and environmental sciences,{2. Agri- cultural {3., Beijing 100193.{2. 3.Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 10002.,{2. 4 college of environmental sciences, {12. Laboratory for earth surface processes, peking university, Beijing {23.,{2. college of Geography and Planning Ludong University Yantai 264025 China Key Laboratory of Plant-Soil Interactions Ministry of Education College of Resources and Environmental Sciences China Agricultural University Beijing 100193 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China college of environmental {2. MOE Laboratory for Earth Surface Processes Peking University Beijing 100871 China

Variations in carbon isotopic ratios (δ 13.) of C3.plants and distribution of C4 plants were investigated along an altitudinal transect on the eastern slope of Mount Gongga, and the environmental effects on them were discussed. It is shown that plants with C4 photosynthetic pathway mainly occur at altitudes below 2.00 m a.s.l., suggesting that the low summer temperature is responsible for the distributional pattern. In addition, δ 13. of C3.plants increases with elevation at the region above 2.00 m a.s.l. with the characteristics of humid climate, and the increase rate in δ 13. for C3.plants is about 1.3. per kilometer. Temperature determines the altitudinal trend of δ 13..

关键词： Mount Gongga carbon isotopic ratios C3.C4 plants C4 distribution altitude

同方期刊数据库

Response of remotely sensed Normalized Difference Water Deviation Index to the 2.06 Drought of eastern Sichuan Basin

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Science china earth {2. 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2. GAO ZhiQiang3.& PENG Jian4 1 School of Water Resource and Hydropower, Sichuan university, Chengdu 610065, china 2.National Satellite Meteorological Center, china Meteorological Administration, Beijing 100081, china 3.Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china 4 School of environmental sciences, peking university, Beijing 100871, china 1. School of Water Resource and Hydropower Sichuan University Chengdu 610065 China 2. National Statellite Meteorological Center China Meteorological Administration Beijing 100081 China 3. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 4. School of environmental sciences Peking University Beijing 100871 China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2.06 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2.01―2.06 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2.06 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth {2. in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

“Tali Glaciation” on Massif Diancang

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Science china earth {2. 2007年第11期50卷 1685-1692页

作者： YANG JianQiang1, CUI ZhiJiu2. YI ChaoLu1, SUN JiMin3.& YANG LiRong3.1 Institute of Tibetan Plateau Research, Chinese Academy of sciences, Beijing 100085, china 2.{2. of environmental sciences, peking university, Beijing 100871, china 3.Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 10002., china 1. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. college of environmental {2. Peking University Beijing 100871 China 3. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The term of ''Tali Glaciation'' is nominated from Massif Diancang in Yunnan Province. The confusing process of the term''s being put forward is confirmed through literature checking. Based on several times of field trip, the glacial landforms in this region are studied in detail, and the magnitude of the glaciation was determined. According to the numerical ages from TL, AIMS ^(14)C and OSL dating, the earliest glacial advance on Massif Diancang occurred at 3.—40 ka BP, followed by the advances at the last stage of the last glaciation, the late glacial and neoglations in turn, until glaciers vanished at 1.2.1.5 ca. a BP in this region. It can be concluded that glaciers were limited above 3.00 m a.s.l., and no glaciers existed on the lower part and adjacent mountains since the last glaciation.

关键词： Massif Diancang,Tali Glaciation,glacial landform,glaciation sequence,numerical dating

A study of interaction between surface water and groundwater using environmental isotope in Huaisha River basin

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Science china earth {2. 2006年第12期49卷 1299-1310页

作者： SONG Xianfang1, LIU Xiangchao1, 2. XIA Jun1, YU Jingjie1 & TANG Changyuan1, 3.1. Key Laboratory of Water Cycle and Related Land surface processes, Institute of Geographical {2. and Natural Re- sources Research, Chinese Academy of {2., Beijing 100101, china 2. college of River and Ocean, Chongqing Jiaotong university, Chongqing 400074, china 3. Chiba university, Chiba 2.3.852., Japan 1. Key Laboratory of Water Cycle and Related Land surface processes Institut of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 2. college of River and Ocean Chongqing Jiaotong University Chongqing 400074 China 3. Chiba university Chiba 263-8522 Japan

The surface water and groundwater are important components of water cycle, and the interaction between surface water and groundwater is the important part in water cycle research. As the effective tracers in water cycle research, {2. isotope and hydrochemistry can reveal the interrelationships between surface water and groundwater effectively. The study area is the Huaisha River basin, which is located in Huairou district, Beijing. The field surveying and sampling for spring, river and well water were finished in 2.02.and 2.03. The hydrogen and oxygen isotopes and water quality were measured at the laboratory. The spatial characteristics in isotope and evolution of water quality along river lines at the different area were analyzed. The altitude effect of oxygen isotope in springs was revealed, and then using this equation, theory foundation for deducing recharge source of spring was estimated. By applying the mass balance method, the annual mean groundwater recharge rate at the catchment was estimated. Based on the groundwater recharge analysis, combining the hydrogeological condition analysis, and comparing the rainfall-runoff coefficients from the 1960s to 1990s in the Huaisha River basin and those in the Chaobai River basin, part of the runoff in the Huaisha River basin is recharged outside of this basin, in other words, this basin is an un-enclosed basin. On the basis of synthetically analyses, combining the compositions of hydrogen and oxygen isotopes and hydrochemistry, geomorphology, geology, and watershed systems characteristics, the relative contributions between surface water and groundwater flow at the different areas at the catchments were evaluated, and the interaction between surface water and groundwater was re- vealed lastly.

关键词： environmental isotope,hydrochemistry,surface water,groundwater,interaction.

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china earth {2. 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3.& YE Xianren2.1. Resources and {3. School, Lanzhou university, Lanzhou 73.000,{2. 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of sciences, Lanzhou 73.000,{2. 3. college of Resources Science & Technology, Beijing Normal university, Beijing 100875,{2. 1. Resources and environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. college of Resources Science & Technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of eastern{3.; ratios of ~3.e/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3.e from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.