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Journal of Mountain science 2011年第6期8卷 845-854页

作者： YANG Zisheng HAN Huali ZHAO Qiaogui Institute of Land ＆ resources and sustainable Development Yunnan University of Finance and Economics Kunming 650221 China southwest University Chongqing 400715 China Department of Land ＆ resources of Yunnan Province Kunming 650224 China

There have been few in-depth quantitative studies on soil erosion control and the ecological effects of land use changes. soil erosion is the first eco-environmental problem particularly in mountainous areas. A major problem in the conversion of farmland to forest is to control soil erosion and improve ecological environment and thus to improve land use sustainability. We report results of calculation and analysis on soil erosion from converted farmland parcels in city of Mangshi （near the sW frontier of china） and the surrounding areas before and after the nine-year （2.00-2.09） project of converting farmland to forest. There was increased water conservation effect, as a result of decreased soil erosion. The average erosion modulus of the farmland returning to eco-friendly uses decreased by 5,535.59 t/km2.a and the control degree of soil erosion modulus reached 71.00%. The increased soil erosion after the returning in the typical sample area ＂did not drop, but increased＂ as the terraced fields decreased but sloping farmland inereased and yet woodland decreased.

关键词： soil erosion control degree The projectof converting farmland to forest converted farmland

Interactive Effects of Lead and Bensulfuron-Methyl on Decomposition of ^(14)c-Glucose in Paddy soils

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Pedosphere 2009年第5期19卷 577-587页

作者： HOU Xian-Wen WU Jian-Jun XU Jian-Ming TANG cai-Xian Institute of soil and Water resources and environmental {2. Zhejiang Provincial Key Laboratory of SubtropicalSoil and Plant Nutrition Zhejiang University Hangzhou 310029 （China） Institute of environmental and Plant Protection Chinese Academy of Tropical Agricultural Sciences Danzhou 571737（China） Department of Agricultural sciences La Trobe University Victoria 3086 （Australia）

Little information is available on the interactive effects of inorganic and organic pollutants on carbon utilization by soil *** study examined the effects of two common soil pollutants,lead(Pb) and bensulfuron-methyl herbicide(BsM),on decomposition of an adscititious carbon source(14c-glucose).Two contrasting paddy soils,a silty clay soil and a clay loam soil,were incubated with different concentrations and combinations of pollutants for 60 *** rotatable central composite design was adopted to design the combinations of the pollutant concentrations so that rate response curves could be *** decomposition of 14c-glucose occurred in the first three days for both soils where no Pb or BsM was added(control).Overall,63%-64% of the added 14c-glucose was decomposed in the control over the 60-day *** addition of Pb or BsM significantly decreased the decomposition of 14c-glucose during the first week but increased the decomposition thereafter;as a result,the percentages of 14c-glucose decomposed(57%-77%) over the 60-day period were similar to or higher than those of the *** of the pollutants in combination did not further inhibit decomposition compared with the ***,decomposition rates were lower in the silty clay soil than in the clay loam soil,which was related to the soil texture,cation exchange capacity,and *** relationship between the decomposition rates and the pollutants could be well characterized by the quadratic regression orthogonal rotation *** initial antagonistic effects of the pollutants followed by the synergistic effects on microbial activity might result from changes of the concentrations of the pollutants.

关键词： carbon source compound pollution herbicide microbial activity

Land Use and soil Organic carbon in china’s Village Landscapes

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Pedosphere 2010年第1期20卷 1-14页

作者： JIAO Jia-Guo YANG Lin-Zhang WU Jun-Xi WANG Hong-Qing LI Hui-Xin E. c. ELLIs Department of resources and environmental {2.s Nanjing Agricultural University Nanjing210095 （China） Institute of soil science Chinese Academy of Sciences Nanjing 210008 （China） Department of Agronomy and Agroecology China Agricultural University Beijing 100094 （China） Department of Geography ＆ environmental systems University of Maryland Baltimore County Baltimore 21250 （USA） center for Louisiana Inland Water studies University of Louisiana at Lafayette Lafayette Louisiana （USA）

Village landscapes, which integrate small-scMe agriculture with housing, forestry, and a host of other land use practices, cover more than 2.million square kilometers across china. Village lands tend to be managed at very fine spatial scales （≤ 30 m）, with managers both adapting their practices to existing variation in soils and terrain （e.g., fertile plains vs. infertile slopes） and also altering soil fertility and even terrain by terracing, irrigation, fertilizing, and other land use practices. Relationships between fine-scale land management patterns and soil organic carbon （sOc） in the top 30 cm of village soils were studied by sampling soils within fine-scale landscape features using a regionally weighted landscape sampling design across five environmentally distinct sites in china. sOc stocks across china＇s village regions （5 Pg c in the top 30 cm of 2.×10^6 km^2. represent roughly 4% of the total sOc stocks in global croplands. Although macroclimate varied from temperate to tropical in this study, sOc density did not vary significantly with climate, though it was negatively correlated with regional mean elevation. The highest sOc densities within landscapes were found in agricultural lands, especially paddy, the lowest sOc densities were found in nonproductive lands, and forest lands tended toward moderate sOc densities. Bue to the high sOc densities of agricultural lands and their predominance in village landscapes, most village sOc was found in agricultural land, except in the tropical hilly region, where forestry accounted for about 45% of the sOc stocks. A surprisingly large portion of village sOc was associated with built structures and with the disturbed lands surrounding these structures, ranging from 〉 18% in the North china Plain to about 9% in the tropical hilly region. These results confirmed that local land use practices, combined with local and regional variation in terrain, were associated with most of the sOc variation within and across china＇s

关键词： agriculture land cover change land use change soil carbon sequestration spatial heterogeneity

Magnetostratigraphy of the late cenozoic Laojunmiao anticline in the northern Qilian Mountains and its implications for the northern Tibetan Plateau uplift

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science china Earth sciences 2005年第7期 1040-1051页

作者： FANG Xiaomin1,2. ZHAO Zhijun3,2. LI Jijun2. YAN Maodu2. PAN Baotian2. sONG chunhui2.& DAI shuang2. 1. Institute of Tibetan Plateau Research, chinese Academy of sciences, Beijing 100085, china 2. Key Laboratory of Western china's environmental systems, Ministry of Education & college of resources and Environment, Lanzhou University, Lanzhou 730000, china 3. college of Geography, Nanjing Normal University, Nanjing 2.0097, china

cenozoic sediments in the foreland basin——Jiuquan Basin in west Hexi corridor recorded tectonic uplift information of the Qilian Mountains. High resolution paleomagnetic dating of the Laojunmiao （LJM） section across the central LJM anticline in the southern Jiuquan Basin reveals ages of the Getanggou Member, Niugetao Member in the shulehe Formation, the Yumen conglomerate, Jiuquan conglomerate and Gobi Formation at >13―8.3 Ma, 8.3―4.9 Ma, 3.66― 0.93 Ma, 0.84―0.14 Ma and 0.14―0 Ma, respectively. sedimentary evolution study suggests that the Qilian Mountains should begin to rise gradually since8―6.6 Ma, accompanied by sedimentary environments changing from lacustrine mudstones-sandstones to alluvial conglom- erates. Rapid uplift of the Qilian Mountains began at3.66 Ma, followed by a series of stepwise or intermittent intensive uplifts at about 2. Ma, 0.93―0.84 Ma and 0.14 Ma, which finally resulted in the present high Qilian Mountains.

关键词： Qilian Mountains Qinghai-Tibetan Plateau Jiuquan Basin magnetostratigraphy.

Applications of online monitoring technology for tailings dam on digital mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 604-609页

作者： YU Guang-ming1, sONG chuan-wang1, ZOU Jing-bo1, WU Yan-xia1, PAN Yong-zhan1, LI Liang1, LI Ran1, WANG Pei-shou2. WANG Yan-lei2.1. school of civil Engineering, Qingdao Technological University, Qingdao 2.6033, china 2. Hedong Goldmine, Zhaojin Mining Industry company, Zhaoyuan 2.5400, china school of civil Engineering Qingdao Technological University Qingdao 266033 China Hedong Goldmine Zhaojin Mining Industry Company Zhaoyuan 265400 China

considering its structural features, geometric shapes, service mode, environmental media, mechanical behavior, etc, the special nature and complexity of tailings dam were summarized. The technical approach to safety management for tailings dam was proposed, which is the on-line automated monitoring and early warning information. The results show that a strong theoretical basis can be provided for security monitoring and security management of tailings dam. Online automated monitoring system for tailings dam has full implementation of the information. It is applied widely in Lingnan gold mine, Xiadian gold mine and Hedong gold mine in Zhaoyuan, shandong Province, and achieves good effect.

关键词： digital mine tailings dam online monitoring security monitoring digitization

Paleomagnetic Excursions Recorded in the Yanchi Playa in Middle Hexi corridor, NW china since the Last Interglacial

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Journal of Mountain science 2004年第2期1卷 128-142页

作者： YANGTaibao YUYongtao LIJijun ANcongrong LIUJinfeng ZHANGJunyan KeyLaboratoryofWesternenvironmentalchanges ChineseMinistryofEducationLanzhouUniversityLanzhou730000China DepartmentofGeography SchoolofGeosciencesNanjingNormalUniversityNanjing210097China InstituteofGeologyandGeophysics ChineseAcademyofSciencesBeo＇ing100029China

Paleomagnetic determinations on lithological profiles of two paralleled[( )-2.5(long )]drilling cores covering the past 130 kyr B.P., GT40 and GT60, from the Yanchi Playa in the arid Northwestern china, indicate that a series of pronounced paleomagnetic excursions have been documented. By correlating our results with published regional and worldwide reports, 4 excursion events out of 10 apparent reversal signals (labeled from GT-1 to GT-10) were identified as excursion events coeval with the Mono Lake Event ([(2..4)( )]kyr~[(2..8)( )]kyr), Laschamp Event ([(43.3)( )]kyr^40.5 kyr), Gaotai Event (82.8 kyr~[(72.4)2.( )]kyr) and the Blake Event (12..4 kyr^113.3 kyr), respectively. GT-9 correlates with the above-mentioned Gaotai Event, GT-7 and GT-6 correspond to two stages of the Laschamp Event and GT-5 to the Mono Lake Event. It is noteworthy that the so-called Gaotai Event has not been reported as a pronounced paleomagnetic excursion in the Northwestern china. Every magnetic excursion event corresponds to paleointensity minima, anteceding those established abrupt paleoclimatic change events, such as the Younger Drays and the Heinrich Events (H1-H6)[(. )-2.0( )]Here,[( )-2.0( )]we tentatively[( )-2.0( )]propose that these geomagnetic excursions/reversals can be viewed as precursors to climate abruptness. During the transitional stages when the earths magnetic field shifted between a temporal normal and a negative period, the earths magnetic paleointensity fell correspondingly to a pair of minima. Although more precise chronology and more convincing rock magnetic parameter determinations are essentially required for further interpretation of their intricate coupling mechanism, these results may have revealed, to some extent, that the earths incessantly changing magnetic field exerts an strong influence on the onset of saw-tooth shaped abrupt climate oscillations through certain feedback chains in arid {2. Asia or even North Hemispheric high latitude regions.

关键词： Paleomagnetism geomagnetic excursion the Late Pleistocene arid Northwestern china

The vegetation and climate change during Neocene and Early Quaternary in Jiuxi Basin, china

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science china Earth sciences 2005年第5期 676-688页

作者： MA Yuzhen 1 , FANG Xiaomin 1,2., LI Jijun 1 , WU Fuli 1 & ZHANG Jun 1 1. Key Laboratory of Western china’s environmental systems and college of {2. and Environment, Lanzhou University, Lanzhou 730000, china 2. state Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, chinese Academy of sciences, Xi’an 710075, china

sporopollen record in the Laojunmiao section at Yumen in the Hexi corridor foreland depression at the northern margin of the Tibetan Plateau revealed that during the period of 13.0―11.15 Ma the ecological environment of the Jiuxi Basin is characterized by steppe vegetation and a semi-moist climate. During 11.16―8.60 Ma prevailed forests of cypress and a still warmer, moister climate; steppe vegetation and dry climate began probably at about 8.6 Ma. Although aridification had been relaxed time and again during 8.40―6.93 Ma (forest-steppe, warm-semi-moist), 6.64―5.67 Ma (open-forest and steppe, warmer-semi-moist) and 5.42.4.96 Ma (steppe, semi-arid), the climate in the region became drier and drier in response to the fre- quent occurrence of aridity during 6.93―6.64 Ma (steppe, semi-arid), 5.67―5.42.Ma (de- sert-steppe, arid), 3.66―3.30 Ma (desert-steppe, arid) and 2.56―2.2. Ma (desert, arid). Perhaps the important findings of our study are the notable expansion of drought-enduring plants during 3.66―3.30 Ma and about 2.56 Ma and the replacement of vegetation by vast arid desert.

关键词： Tibetan Plateau Hexi corridor sporopollen record ecological environment vegetation evolution aridific-ation.

The spatial and temporal distribution of microalgae in the south china sea:evidence from GIs-based analysis of 18s rDNA sequences

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science china(Life sciences) 2008年第12期51卷 1121-1128页

作者： LI LüYan1, HUANG QiaoJuan1, WU shuHui1, LIN Duan2. cHEN JiaHui2.& cHEN YueQin1 1 Key Laboratory of Gene Engineering of the Ministry of Education, state Key Laboratory for Biocontrol, sun Yat-sen University, Guangzhou 5102.5, china 2.south china sea {2. Monitoring center, state Oceanic Administration, Guangzhou 510300,china Key Laboratory of Gene Engineering of the Ministry of Education State Key Laboratory for Biocontrol Sun Yat-Sen University Guangzhou China south china sea environmental Monitoring center State Oceanic Administration Guangzhou China

The purpose of this study was to estimate the spatial and temporal variation of microalgae in the south china sea and to demonstrate the environmental factors controlling the diversity of microalgae by GIs (geographic {2. system)-based analysis of 18s rDNA sequences. six 18s rDNA libraries were constructed from environmental samples collected at different sites in the study area, and more than 600 18s rDNA sequences were determined. The rDNA sequence data were then analyzed by DIVA-GIs software to display the spatial and temporal variation of phytoplankton’s composition. It was shown that the autotrophic eukaryotic plankton dominated over the heterotrophic cells in most of our clone libraries, and the dominating phytoplankton was Dinophyceae except for Bacillariophyta at the Xiamen harbor. The percentages of these two groups were controlled by water temperature and salinity. Our results also revealed that the species composition of chlorophyta showed a close relationship with latitude, changing from Prasinophyceae at the high latitude to Trebouxiophyceae at the low latitude. several newly c.a.s.fied picoplankton lineages were first uncovered in the south china sea, including the pico-sized green alga Ostreococcus sp. and Picochlorum eukaryotum, and picobiliphytes, which was just discovered in 2.07 with unknown affinities to other eukaryotes. Their spatial and temporal variation were also analyzed and discussed.

关键词： microalgae GIs-based analysis 18s rDNA south china sea

characterizing the Mass Elevation Effect across the Tibetan Plateau

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Journal of Mountain science 2018年第12期15卷 2651-2665页

作者： HAN Fang ZHANG Bai-ping ZHAO Fang WAN Li TAN Jing LIANG Tian school of civil and Architectural Engineering, shandong University of Technology Institute of Geographic sciences and Natural resources Research, state Key Laboratory of resources and environmental information system, chinese Academy of sciences college of Environment and Planning, Henan University chinese Research Academy of environmental sciences Beijing Aerospace TITAN Technology co., Ltd school of civil and Architectural Engineering Shandong University of TechnologyZibo 255000China Institute of Geographic sciences and Natural resources Research State Key Laboratory of Resources and Environmental Information SystemChinese Academy of SciencesBeijing 100101China college of Environment and Planning Henan UniversityKaifeng 455000China chinese Research Academy of environmental sciences Beijing 100012China Beijing Aerospace TITAN Technology co. LtdBelling 100083China

It is over 110 years since the term Mass Elevation Effect(MEE) was proposed by A. D. Quervain in 1904. The quantitative study of MEE has been explored in the Tibetan Plateau in recent years; however, the spatial distribution of MEE and its impact on the ecological pattern of the plateau are seldom known. In this study, we used a new method to estimate MEE in different regions of the plateau, and, then analyzed the distribution pattern of MEE, and the relationships among MEE, climate, and the altitudinal distribution of timberlines and snowlines in the Plateau. The main results are as follows:(1) The spatial distribution of MEE in the Tibetan Plateau roughly takes on an eccentric ellipse in northwestsoutheast trend. The chang Tang Plateau and the middle part of the Kunlun Mountains are the core area of MEE, where occurs the highest MEE of above 11℃; and MEE tends to decreases from this core area northwestward, northeastward and southward;(2. The distance away from the core zone of the plateau is also a very important factor for MEE magnitude, because MEE is obviously higher in the interior than in the exterior of the plateau even with similar mountain base elevation(MBE).(3) The impacts of MEE on the altitudinal distribution of timberlines and snowlines are similar, i.e., the higher the MEE, the higher timberlines and snowlines. The highest timberline(4600–4800 m) appears in the lakes and basins north of the Himalayas and in the upper and middle reach valleys of the Yarlung Zangbo River, where the estimated MEE is 10.2.2.℃–10.6904℃. The highest snowline(6000–62.0 m) occurs in the southwest of the chang Tang Plateau, where the estimated MEE is 11.2.59°c–11.5488℃.

关键词： Mass Elevation Effect (MEE) Distribution Pattern Timberline snowline Tibetan Plateau

soil Quality Assessment Using Weighted Fuzzy Association Rules

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Pedosphere 2010年第3期20卷 334-341页

作者： XUE Yue-Ju LIU shu-Guang HU Yue-Ming YANG Jing-Feng south china Agricultural University Guangzhou 510642 (China) U.s. Geological survey center for Earth resources Observation and science Sioux Falls SD 57198 (USA) Geographic information science center of Excellence South Dakota State University Brookings SD 57007 (USA)

Fuzzy association rules (FARs) can be powerful in assessing regional soil quality, a critical step prior to land planning and utilization; however, traditional FARs mined from soil quality database, ignoring the importance variability of the rules, can be redundant and far from optimal. In this study, we developed a method applying different weights to traditional FARs to improve accuracy of soil quality assessment. After the FARs for soil quality assessment were mined, redundant rules were eliminated according to whether the rules were significant or not in reducing the complexity of the soil quality assessment models and in improving the comprehensibility of FARs. The global weights, each representing the importance of a FAR in soil quality assessment, were then introduced and refined using a gradient descent optimization method. This method was applied to the assessment of soil resources conditions in Guangdong Province, china. The new approach had an accuracy of 87%, when 15 rules were mined, as compared with 76% from the traditional approach. The accuracy increased to 96% when 32.rules were mined, in contrast to 88% from the traditional approach. These results demonstrated an improved comprehensibility of FARs and a high accuracy of the proposed method.

关键词： accuracy comprehensibility global weights