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Physical mechanisms of plant roots affecting weathering and leaching of loess soil

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science china Earth sciences 2006年第9期49卷 1002-1008页

作者： LI Yong1,2, ZHANG Qingwen1,2, WAN Guojiang3. HUANG Ronggui3. PIAO Hechun3. BAI Lingyu2 & LI Lu2 1. state Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau, institute of soil and Water Conservation, {3. academy of sciences, Yangling 712100, china 2. institute of Agro-Environment and sustainable Development, {3. academy of Agricultural sciences, Beijing 100081, china 3. institute of Geochemistry, {3. academy of sciences, Guiyang 550002, china 1. state Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling 712100 China 2. institute of Agro-Environment and sustainable Development Chinese Academy of Agricultural Sciences Beijing 100081 China 3. institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Plant roots have potential impacts on soil mineral weathering and *** objective is to understand the physical mechanisms of plant roots affecting weathering andleaching of loess soil. Root densities were measured through the method of a large-size dug profile,and transport fluxes of soil elements were determined using an undisturbed monolith soilinfiltration device on the hilly and gully regions of the chinese Loess Plateau. The results showthat the improvement effects of soil environment by plant roots are mainly controlled by the densityand weight of the fibrous roots with the diameters less than 1 mm. Plant roots have the strongereffects on soil physical properties than chemical properties. The principal components analysis(PCA) indicates that soil physical properties by plant roots account for 56.7% of variations in soilenvironment whereas soil chemical properties and pH contribute about 24.2% of the soil *** roles of plant roots in controlling soil weathering and leaching increased in the followingorder: infiltration enhancement > increase of bio-active substance > stabilization of soilstructure. The effects of plant roots on soil mineral weathering and leaching can be quantifiedusing the multiple regression models with the high prediction accuracies developed in this study.

关键词： plant roots, soil weathering and leaching rates, soil environment field, principal components analysis (PCA), chinese Loess Plateau.

Nitrogen isotopic geochemical characteristics of crude oils in several basins of china

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science china Earth sciences 2005年第8期48卷 1211-1219页

作者： CHEN Chuanping1,2, MEI Bowen1 & CAO Yacheng3.1. Jianghan Petroleum University, Jingzhou 43.100, china 2. Huazhong University of science and Technology, Wuhan 43.047, china 3. Nanjing {3. of soil science, chinese academy of sciences, Nanjing 210008, china 1. Jianghan Petroleum University 434100 Jingzhou China 2. Huazhong University of science and Technology 430047 Wuhan China 3. Nanjing institute of soil science Chinese Academy of Sciences 210008 Nanjing China

Nitrogen isotopic ratios of crude oils with different physical and chemical properties in several basins of china have been measured and their geochemistry has been studied ele-mentally combined with molecular organic geochemistry methods. The data indicate that δ 15N is in the range of ?6‰-20‰. They vary with the oils in different sedimentary types of basins. The oils forming in the limnic environment have lower δ 15N with the value of about 1‰-5‰ whereas the oils in saline or semi-saline environment have higher δ 15N, with most samples being above 10‰ and some exceeding 17‰. The average nitrogen isotopic ratio of oils from the Ordovician formation in the Tarim Basin is the lowest, with most samples having δ 15N below zero, which reflects possibly the characteristic of the oils originating mainly from the organic matter formed in marine carbonate sedimentary environment. The δ 15N distribution can be altered by fractionation. It increases obviously because of biodegradation and decreases during hydrocarbon migration. However, the effect of nitrogen isotopic fractionation in the short distance migration is uncon-spicuous.

关键词： nitrogen isotope, crude oil, sedimentary environment, isotopic fractionation, china.

Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1,2, LI Anchun1, HU Ningjing2,3. FU Yongtao1& MA Zhibang4 1. institute of Oceanology, chinese academy of {{3., Qingdao 266071, china 2. Graduate school of the chinese academy of {{3., Beijing 10003., china 3. institute of soil science, chinese academy of {{3., Nanjing 210008, china 4. institute of Geology and Geophysics, chinese academy of {{3., Beijing 100029, china 1. institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate school of the chinese academy of sciences Beijing 100039 China 3. institute of soil science Chinese Academy of Sciences Nanjing 210008 China 4. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, sr-Nd isotopic ratio, magmatic evolution.

^(40)Ar/^(3.)Ar dating of shear deformation of the Xianshuihe fault zone in west sichuan and its tectonic significance

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science china Earth sciences 2004年第9期47卷 794-803页

作者： ZHANG Yueqiao1, CHEN Wen2, 3.& YANG Nong1 1. institute of Geomechanics, chinese academy of Geological {{3., Beijing 100081, china 2. institute of Geology, chinese academy of Geological {{3., Beijing 10003., china 3. institute of Geology and Geophysics, chinese academy of {{3., Beijing 100029, china institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (12-10 Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 3.0℃. The late event (5-3.5 Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the sE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/3.Ar dating, late Cenozoic.

Effects of chlorothalonil and carbendazim on nitrification and denitrification in soils

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Journal of Environmental sciences 2009年第4期21卷 458-467页

作者： LANG Man, CAI Zucong state Key Laboratory of soil and sustainable Agriculture, institute of soil {3., chinese academy of {3.s,Nanjing 210008, china [a]state Key Laboratory of soil and sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

The effects of chlorothalonil and carbendazim on nitrification and denitrification in six soils in upland and rice paddy environments were investigated. Laboratory aerobic （60% water holding capacity） and anaerobic （flooded） conditions were studied at 25℃ and fungicide addition rates of 5.5 mg/kg A. I. （field rate, FR）, 20 times （20FR） and 40 times （40FR） field rate, respectively. The results indicated that chlorothalonil at the field rate had a slight inhibitory effect on one soil only, and that soil did not nitrify much in the first place. But chlorothalonil at higher rates inhibited nitrification significantly in all soils. For soils JXP and JXU with a pH of less than 5.0, chlorothalonil almost completely stopped their nitrification at 20FR and 40FR during the whole 14 d incubation period. For soils HNP and HNU with a pH of greater than 8.0, chlorothalonil also significantly inhibit nitrification at 20FR and 40FR （p 〈 0.05）. However, NH4＋ that was added to the soil was also almost completely nitrified by the end of the incubation period in these two soils. The effects of chlorothalonil at 20FR and 40FR on the nitrification of JsP and JsU soils, with a pH of 5.4 and 7.2, respectively, were intermediate between the other soil types. Chlorothalonil had no effect on denitrification at the field rate and had little effect at the higher rates of application in some soils. Carbendazim had essentially no effect on nitrification and denitrification in soils assessed.

关键词： fungicide nitrification denitrification chlorothalonil carbendazim

Two possible mechanisms for vortex self-organization

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science china Earth sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2, ZHOU Xiuji1 & GAO shouting3.1. chinese academy of Meteorological sciences, Beijing 100081,{3. 2. Department of space Information science, Nanjing University of Information science and Technology, Nanjing 210044,{3. 3. institute of Atmospheric Physics, chinese academy of sciences, Beijing 100029,{3. 2. Department of Environmental science Nanjing University of Information Science and Technology Nanjing 210044 China 1. chinese academy of Meteorological sciences Beijing 100081 China 3. institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

strong decays of N~*(153.) in an extended chiral quark model

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science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN Chunsheng1,2,3.& ZOU Bingsong1,2,3.1 institute of High Energy Physics,chinese academy of {{3.,Beijing 100049,china 2 Theoretical Physics Center for science Facilities,chinese academy of {{3.,Beijing 100049,china 3.Graduate University of chinese academy of {{3.,Beijing 100049,china institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Theoretical Physics Center for science Facilities Chinese Academy of Sciences Beijing 100049 China Graduate University of chinese academy of sciences Beijing 100049 China

The strong decays of the N*(153.) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(153.) contribute significantly to the N*(153.) → Nπ and N*(153.) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(153.) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(153.) strong decays five-quark components

Integrated precise orbit determination of shenzhou IV unmanned spacecraft

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science china(Technological sciences) 2004年第5期47卷 518-525页

作者： L Congmin1,2, GU Yidong3. LIN Baojun3.& GUO Jiong3.1. Center for space science and Applied Research, chinese academy of sciences, Beijing 100080, china 2. Graduate school of the chinese academy of sciences, Beijing 10003., china 3. General Establishment of space science and Application, chinese academy of sciences, Beijing 100080, china Correspondence should be addressed to L Congmin 1. Center for space science and Applied Research Chinese Academy of Sciences 100080 Beijing China 2. Graduate school of the chinese academy of sciences 100039 Beijing China 3. General Establishment of space science and Application Chinese Academy of Sciences 100080 Beijing China

Considering the characteristic orbit of shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPs, sLR and UsB observation data jointly plus precise ionosphere corrections to GPs observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2 m.

关键词： shenzhou IV unmanned spacecraft integrated precise orbit determination GPs sLR UsB.

Discovery of immune related factors in Fenneropenaeus chinensis by annotation of EsTs

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Progress in Natural science:Materials International 2004年第1期14卷 48-55页

作者： sHEN Yaoqing 1,2 , XIANG Jianhai 1*, WANG Bing 1,2 , LI Fuhua 1 and TONG Wei 3.1. Experimental Marine Biology Laboratory, institute of Oceanology, chinese academy of {{3., Qingdao 266071,china 2. Graduate school of the chinese academy of {{3., Beijing 10003., china 3. Genomics & Bioinformatics institute, chinese academy of {{3., Beijing 10{13.0, china) chinese Acad sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China chinese Acad sci Grad Sch Beijing 100039 Peoples R China chinese Acad sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 10446 expressed sequence tags (EsTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EsT analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these EsTs in order to promptly find possible functional genes, especially for immune related factors. About 4% of the EsTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These EsTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics EsTs immune factors