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The potential effect of variations in climate and agricultural practice on N_2. emissions (Ⅱ)——Variations in agricultural practice

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Chinese Science Bulletin 1999年第S2期44卷 97-99页

作者： XU Wenbin~(1,2., HONG Yetang~1, CHEN Xuhui~3, LI Changsheng~4, LIN Qinghua~1 and WANG Yu~1, 1. State Key Laboratory of environmental Geochemistry, institute of Geochemistry, Chinese Academy of Sciences,{2. 2. institute of Environment and Resources Chemistry, Zhejiang University, Hangzhou 31002., china 3. Soil and Fertilizer institute, guizhou Academy of Agricultural Sciences, guiyang 550013, china 4. institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, USA State Key Laboratory of environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China institute of Environment and Resources Chemistry Zhejiang University Hangzhou 310027 China Soil and Fertilizer institute Guizhou Academy of Agricultural Sciences Guiyang 550013 China institute for the Study of Earth Oceans and Space University of New Hampshire Durham NH United States

WE expanded Decomposition-Denitrification （DNDC）modeling study to systematically assess the potential effect of farming practice on N2. emission by choosing a corn-rape rotation and a soybean-winterwheat rotation fi... 详细信息

WE expanded Decomposition-Denitrification （DNDC）modeling study to systematically assess the potential effect of farming practice on N2./sub>O emission by choosing a corn-rape rotation and a soybean-winterwheat rotation field in guizhou Province, westsouthern china, asN2./sub>O emission from subtropical agricultural soil study plots. These sensitivity studies address questions relevant to issue of how change in fanning practice might be used to mitigate emissions. Manure additions had the most pronounced impact on N2./sub>O emissions of farming practice simulatedand the influence of manure addition was nonlinear （fig. 1）. This result is consistent with previous studies for an Iowa corn field. The addition of manure remarkably elevates the level of organic carbon, enhances soil nitrogen mineralization, and increases the efficiency of N2./sub>O production. Simulated results alsoshowed that the influence of manure additions on N2./sub>O emission from soybean-winter wheat field had

关键词： N2. emission farming practice potential effect agricultural soil.

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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 Laboratory of environmental Geochemistry, institute of Geochemistry, Chinese Academy of Sciences,{2.

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.

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The first finding of superhigh concentration of REE-rich bed in carbonate rock weathering crusts and its siginificance

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Chinese Science Bulletin 1999年第S2期44卷 104-106页

作者： JI Hongbing, WANG Shijie, ZHOU Dequan, OUYANG Ziyuan and SUN Chengxing State Key Laboratory of environmental Geochemistry, institute of Geochemistry, Chinese Academy of Sciences,{2. State Key Laboratory of environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE Pingba soil profile developed on the bedrock Triassic dolomitite and morphologically located in uplandin karst terrain in Central guizhou, china was proven to be in-situ dolomitite weathering pedogeneticproduct. Continuous sampling method was used for taking samples from man-made excavated pit fromthe Pingba profile. REE for samples was measured on ELEMENT ICP-MS in the {2. of Geochemistry, CAS. The standard reference samples GSR-6 and GSS-1,4,7 were used to monitor the precisionof REE measurement. The measurement error was less than ≤10%. For PB-T1 sample, the coefficientof variation (CV) of three analytical run precision is: La, Ce, Pr, Nd, Ho, Er≤10%; Sm, Eu, Dy,Tm≤15%; Y, Lu, Gd, Tb≤2.%.

关键词： superhigh REE concentration weathering crust carbonate rock.

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Organic Phosphorus in Shallow Lake Sediments in Middle and Lower Reaches of the Yangtze River Area in china

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Pedosphere 2008年第3期18卷 394-400页

作者： JIN Xiang-Can WANG Sheng-Rui CHU Jian-Zhou WU Feng-Chang State environmental protection Key Laboratory for Lake Pollution Control Research Center of Lake Eco-EnvironmentChinese Research Academy of Environmental Sciences Beijing 100012 （China） Colleges of Resource and Environment Hebei Agriculture University Baoding 071001 （China） State Key Laboratory of environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang550002 （China）

Thirteen sediment core samples(0-10 cm) were taken from the seven lakes in the middle and lower reaches of the Yangtze River to determine the contents and distributions of organic phosphorus(P) fractions in the sediments of the shallow lakes in the *** organic P fractions in the sediments were in the order of moderately labile organic P(MLOP) > moderately resistant organic P(MROP) > highly resistant organic P(HROP) > labile organic P(LOP),with average proportional ratios of 13.2.2.8:1.3:***,MLOP,and MROP were significantly related to the contents of total organic carbon(TOC),water-soluble P(WSP),algal-available P(AAP),NaHCO3-extractable P(Olsen-P),total P(TP),organic P(OP),and inorganic P(IP).However,HROP was significantly related to OP and weakly correlated with TOC,WSP,AAP,Olsen-P,TP or *** suggested that organic P,especially LOP and MLOP in sediments,deserved even greater attention than IP in regards to lake *** terms of organic P,sediments were more hazardous than soils in lake *** OP concentrations were higher in moderately polluted sediment than those in heavily polluted sediment,LOP and MLOP were higher in the heavily polluted sediment,which indicated that heavily polluted sediment was more hazardous than moderately polluted sediment in lake eutrophication.

关键词： bioavailability chemical extracted phosphorus lake sediment middle and lower reaches of the Yangtze River area organic phosphorus fractions

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Existing state of Cd in the Niujiaotang Cd-rich zinc deposit, guizhou, china

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Chinese Science Bulletin 1999年第S2期44卷 182-185页

作者： YE Lin and LlU Tiegeng Open Laboratory of Ore Deposit Geochemistry, institute of Geochemistry, Chinese Academy of Sciences, guiyang 550002. china Open Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

As a dispersed element, cadmium is difficult to enrich and mineralize. As the Cd tetrahedron is similar tothat of Zn in covalent radius and crystal structure, both the elements possess similar geochemical *** is present mainly as isomorphous impurity in sphalerite. So Cd, as an associated element, occurslargely in Pb-Zn deposits. Current research both at home and abroad is focused on the environmental effect of Cd, but little work has been done on the mechanism of enrichment and mineralization of Cd. Theresearch papers available are mostly restricted to the ordinary geochemical characteristics of CdFrom the end of 1980s to the early 1990s, independent ore deposits of Te, Tl and other dispersed elements were discovered in the region of Southwest china. Prof. Tu Guangzhr proposed that dispersed elements can form their independent ore deposits. It has been realized that the dispersed

关键词： Cd Niujiaotang Cd-rich zinc deposit guizhou.

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Simulating experiment on soaking and leaching of Cd in the Niujiaotang Cd-rich Zn deposit, guizhou Province, china

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Chinese Science Bulletin 1999年第S2期44卷 190-193页

作者： YE LJn and LlU Tiegeng Open Laboratory of Ore Deposit Geochemistry, institute of Geochemistry, Chinese Academy of Sciences, guiyang 550002. china Open Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

CADMIUN is a dispersed element and has long been explored and utilized as a by-product of Pb-Zn *** research on Cd is focused on the following aspects: (i) environmental effects due to the migration and enrichment of Cd as a heavy metal poisonous element in water (rivers, lakes, industrially discharged waste water), sediments and soils. The research paper concerned can be seen in variousjournals of environmental science; and (ii) exploration of the existing forms of Cd and its independentminerals and ordinary geological problems. However, many researchers have paid little attention tothe geochemical behavior of Cd and its environmental effects under supergene weathering-leaching conditions in Cd-bearing Pb-Zn deposits. Cd can be separated from Zn in the supergene weathering processand its sulfate CdS0-4 is easy to dissolve in water. Our preliminary studies showed that Cd can be enrichedto some extent under supergene weathering conditions in Niujiaotang deposit. The stronger the extent

关键词： leaching experiment Cd-rich Zn deposit guizhou.

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The influence of temperature on diurnal and seasonal variations of N_2. flux from agricultural soilis in guizhou

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Chinese Science Bulletin 1999年第S2期44卷 101-102页

作者： XU Wenbin~(1,2., HONG Yetang~1, CHEN Xuhui~3, QIN Song~3 and JIANG Taiming~3 1. State Key Laboratory of environmental Geochemistry, institute of Geochemistry, Chinese Academy of Sciences,{2. 2. institute of Environment and Resources Chemistry, Zhejiang University, Hangzhou 31002., china 3. Soil and Fertilizer institute, guizhou Academy of Agricultural Sciences, guiyang 550013, china

AGRICULTURAL soils are the major anthropogenic source of N2., and temperature is one of the importantenvironmental factors controlling production and emission of N2. from soil. This work focuses on the influence of te... 详细信息

AGRICULTURAL soils are the major anthropogenic source of N2./sub>O, and temperature is one of the importantenvironmental factors controlling production and emission of N2./sub>O from soil. This work focuses on the influence of temperature on diurnal and seasonal variations of N2./sub>O flux from subtropical agricultural *** was done by seasonal measuring N2./sub>O flux and soil temperature at a corn-rape rotation, a soybeanwinter wheat rotation and a fallow field （106°66’E, 2.°50’N, 1140 m a.s.1.）, at Soil and Fertilizer institute, {2. Academy of Agricultural Sciences. Available nitrogen content of above three fields wasapproximately 0.71%, organic matter content 10.6-12.0 g/kg, clay （2.μm） content 2..6%-30.0%, and pH was about 7.5 throughout the whole experiment. Measuring period was between 2. Mar.

关键词： N2. flux temperature diurnal variation seasonal variation agricultural soil.

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Soil Heavy Metal Pollution Around the Dabaoshan Mine,Guangdong Province,china

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Pedosphere 2007年第5期17卷 588-594页

作者： ZHOU Jian-Min DANG Zhi CAI Mei-Fang LIU Cong-Qiang College of environmental Science and Engineering South China University of Technology Guangzhou 510640 （China） Guangdong Key Laboratory of Agro-Environment Integrated Control Guangdong Institute of Eco-Environment and Soil Science Guangzhou 510650 （China） State Key Laboratory of Environment Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 （China）

Soil contamination in the vicinity of the Dabaoshan Mine, Guangdong Province, china, was studied through determi- nation of total concentrations and chemical speciation of the toxic metals, Cu, Zn, Cd, and Pb, using inductively coupled plasma mass spectrometry. The results showed that over the past decades, the environmental pollution was caused by a combination of Cu, Zn, Cd, and Pb, with tailings and acid mine drainage being the main pollution sources affecting soils. Significantly higher levels （P ≤ 0.05） of Cu, Zn, Cd, and Pb were found in the tailings as compared with paddy, garden, and control soils, with averages of 1486, 2.16, 6.42. and 42. mg kg^-1, respectively. These metals were continuously dispersed downstream from the tallings and waste waters, and therefore their concentrations in the paddy soils were as high as 567, 1 140, 2.48, and 191 mg kg^-1, respectively, being significantly higher （P ≤ 0.05） as compared with those in the garden soils. The results of sequential extraction of the above metals from all the soil types showed that the residual fraction was the dominant form. However, the amounts of metals that were bound to Fe-Mn oxides and organic matter were relatively higher than those bound to carbonates or those that existed in exchangeable forms. As metals could be transformed from an inert state to an active state, the potential environmental risk due to these metals would increase with time.

关键词： chemical speciation combined pollution index (CPI) contaminated soil heavy metals

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喀斯特山区先锋植物叶片解剖特征及其生态适应性评价——以贵州花江峡谷区为例

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山地学报 2005年第1期23卷 35-42页

作者：容丽王世杰刘宁杨龙中国科学院地球化学研究所环境地球化学国家重点实验室贵州师范大学地理与生物科学学院贵州师范大学地理与生物科学学院贵州贵阳　550002.州师范大学地理与生物科学学院贵州贵阳　550001 贵州贵阳　550002

通过研究贵州西南部典型喀斯特植被退化区花江峡谷植被现状,选取具一定经济价值和推广价值的先锋植物,采用生物显微制片技术与数理统计方法相结合,报导了6科10种分属不同生活型的植物叶片的解剖结构特征,并进行了比较和解剖因子分析。... 详细信息

通过研究贵州西南部典型喀斯特植被退化区花江峡谷植被现状,选取具一定经济价值和推广价值的先锋植物,采用生物显微制片技术与数理统计方法相结合,报导了6科10种分属不同生活型的植物叶片的解剖结构特征,并进行了比较和解剖因子分析。结果表明研究区喀斯特先锋植物叶片在不同种类之间具有明显差异,这些差异除受遗传因子控制外,环境因子(主要为光照和水分)也有重要作用;生活型不同对先锋植物叶片特征有一定影响,但未表现出规律性。根据叶片适应特征的差异,10种先锋植物可分为3种类型,即旱生或阳生叶类型的构树(Broussonetiapapyrifera)、火棘(Pyracanthafortuneana)、刺槐(Robiniapseudoacacia)、白三叶(Trifoliumrepens);偏中生叶类型(香椿的Toonasinensis)、顶坛花椒(Zanthoxylumplanispinumvar dingtanensis)、黔滇木蓝(In digoferaesquirolii)、忍冬(Lonicerajaponica)、紫云英(Astragalussinicus);偏阴生叶类型的繁缕(Stellariamedia)。

关键词：喀斯特先锋植物叶片解剖特征生态适应性

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A study on excitation of atmospheric gravity waves from annular solar eclipse

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Chinese Journal of Acoustics 1993年第2期12卷 166-183页

作者： LI Qitai(institute of environmental {2. ofguizhou Province. guizhou 550002.XIE Jinlai and YANG Xunren (institute of Acoustics. Academia Sinica Beijing 100080)

Utilizing the data of microbarometric waves on ground level, radiosonde reports and solar radiations obtained from various observation stations in china during the annular solar eclipse on September 2., 1987, the mechanism ,of AGWs excited by the eclipse, the spectral characteristics and the local differences have been studied, and the results have been compared with those from the ionospheric sounding at the same time. It turns out that there were AGWs excited certainly during this annular solar eclipse, their periods are obviously in accordance with the duration of the fluctuation in the direct solar radiation.

关键词： Annular solar eclipse Acoustic gravity wave Dynamical spectra.

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