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Paleoclimatic significance of mineral magnetic properties of loess sediments in northeastern Qinghai-Tibetan Plateau

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Paleoclimatic significance of mineral magnetic properties of...

中国科学院地质与地球物理研究所2003.术年会

作者： WANG Xiaoyong~1,LU Huayu~1,LI Zhen~2, DENG Chenglong~3.TAN Hongbing~4 & SONG Yougui~1 1.State key laboratory of Loess and Quaternary Geology,Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075, China 2.Department of geography,Qinghai {3. university,Xining 810008, China 3.Paleomagnetism laboratory,Institute of Geology and Geophysics, Chinese Academy of Sciences,Beijing 100029,China 4.Institute of Saline Lake,Chinese Academy of Sciences,Xining 810008,China

Loess deposit in the northeastern Qing-hai -Tibetan Plateau offers an excellent record of climate and environment changes in this *** have conducted multiparameter mineral magnetic analyses of samples of loess deposits from the Dongchuan,Lalakou and Panzishan sections. The methods used include magnetic susceptibility,frequency -dependent susceptibility,temperature-dependent susceptibility,isothermal remanent magnetization acquisition, and magnetic hysteresis *** results reveal that magnetite is the dominant contributor to magnetic susceptibility. Maghemite and hematite is also present in the loess layers and paleosol *** higher concentration of maghemite in paleosols suggests that the formation of maghemite occurred during in situ pedogenesis,which plays an important role in the enhancement of the magnetic susceptibility. Similar to that in the Chinese Loess Plateau lying to the east of the Liupan Mountains,magnetic granulometry in the studied loess and paleosols is predominantly pseudo-single-domain(PSD).However,the mean grain-size of the ferrimagnetic minerals in loess is evidently coarser (larger PSD and multidomain-like) than in paleosols(mainly PSD).The magnetic susceptibility of loess and paleosols is positively correlated with the content of ultrafine magnetite /maghemite grains,and hence with the intensity of in situ ***,the enhanced magnetic susceptibility in the studied loess-paleosol sequences can be interpreted as being due to climatically induced in situ pedogenesis.

关键词： mineral magnetism loess-paleosol Qinghai-Tibetan Plateau magnetic susceptibility

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地表滴灌土壤湿润体特征值的经验解

土壤学报 2004年第6期41卷 870-875页

作者：张振华蔡焕杰杨润亚西北农林科技大学教育部旱区农业水土工程重点实验室陕西杨凌712100 烟台师范学院地理与资源管理学院山东烟台264025

粘壤土地表点源入渗试验研究表明 ,其土壤湿润体形状近似为半椭球体 ,水平和竖直方向的最大入渗距离与入渗时间存在极显著的幂函数关系。湿润体体积和灌水量之间存在显著的线性关系 ,在2～ 4Lh-1的滴头流量范围内 ,灌水量相同时不同流... 详细信息

粘壤土地表点源入渗试验研究表明 ,其土壤湿润体形状近似为半椭球体 ,水平和竖直方向的最大入渗距离与入渗时间存在极显著的幂函数关系。湿润体体积和灌水量之间存在显著的线性关系 ,在2～ 4Lh-1的滴头流量范围内 ,灌水量相同时不同流量滴头对应的湿润体体积的最大差异保持在 5 %以内。地表点源入渗过程中 ,土壤湿润体内平均体积含水率的增量和入渗时间、滴头流量无关保持为一定值 ,在本研究条件下为 0 3. 6。综合以上结果。

关键词：湿润体土壤滴灌滴头流量灌水量点源入渗粘壤土特征值近似幂函数

Water Environmental Degradation of the Source Area of the Yellow River on Northeast Qinghai-Tibet Plateau

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Chinese Journal of Population,Resources and Environment 2005年第3期3卷 34-36页

作者： Qi Shanzhong 1, Luo Fang 2 & Xiao Honglang 2 1 College of Population, Resources and Environment, Shandong normal university, Jinan 250014, China 2 Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academic of Sciences, Lanzhou, 73.000, China College of Population Resources and Environment Shandong Normal University Jinan 250014 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academic of Sciences Lanzhou 730000 China

The issue on water environmental degradation in the source area of the Yellow River has been one of very serious ecological and socially economic problems. The temporal-spatial changes of water environment led to the decreasing of land capacity and river disconnecting. The status of water environmental degradation in this paper was analyzed based on the data and field investigation. The results indicated that the surface water area in the region has obviously decreased owing to the climate changes and human irrational use of water resources and the continuous lowering of the regional groundwater table and the steadily decreasing tendency of the flow rate in the source areas of the Yellow River.

关键词： water environmental degradation decreasing of surface water continuous lowering of groundwater table the Yellow River region Qinghai- Tibet Plateau

Plant Diversity Reduces the Effect of Multiple Heavy Metal Pollution on Soil Enzyme Activities and Microbial Community Structure

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Plant Diversity Reduces the Effect of Multiple Heavy Metal P...

第六届全国环境化学大会暨环境科学仪器与分析仪器展览会

作者： Yang Gao~(1,4),Jun Xia~1,Yafeng Wang~2,Chiyuan Miao~3.Pei Zhou~4 (1.key laboratory of Water Cycle and Related Land Surface Processes,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China 2.State key laboratory of Urban and regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China 3.College of Global Change and Earth System Science,Beijing normal university,Beijing 100078,China 4.School of Agriculture and Biology,Shanghai Jiaotong university,Shanghai 200240,China)

＜正＞It is unclear whether certain plant species and plant diversity could offset the impacts of multiple heavy metal pollution on soil microbial structure and soil enzyme *** amplified polymorphic DNA（RAPD） was used to analyze the genetic diversity and microbial similarity in planted and unplanted soil under combined cadmium （Cd） and lead（Pb） pollution.A metal hyperaccumulator,Brassica juncea,and a common plant,Festuca arundinacea Schreb,were used in this *** results showed that micro-organism quantity in planted soil significantly increased,compared with that in

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Theoretical Discussion on Chinese Tourism Development Plan

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Theoretical Discussion on Chinese Tourism Development Plan

第十一届全国经济管理院校工业技术学研究会

作者： Xin GAO 1,Lin''an GAO 2,Shulin ZHANG 1,Qing DONG 3.1.College of geography and Tourism,Chongqing normal university,Chongqing,Shapingba 2.College of commerce,Xi''an Financial Services Institute,Xi''an,Yanta 3.Center for Chinese Language and Culture International Exchange,Chongqing normal university,Chongqing,Shapingba

Tourism development plan plays a more and more important role in practical plan management,and embodies space plan theory in tourism *** on the research summarization,the paper has a discussion on tourism development plan conception,its position in regional development plan system,its classification,and framework of theoretical and technical support system.

关键词： Tourism development plan Classification support system

NPP vulnerability of the potential vegetation of China to climate change in the past and future

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Journal of Geographical Sciences 2017年第2期27卷 131-142页

作者： YUAN Quanzhi WU Shaohong DAI Erfu ZHAO Dongsheng REN Ping ZHANG Xueru key Lab of Land Resources Evaluation and Monitoring in Southwest Ministry of Education Sichuan NormalUniversity Chengdu 610068 China Institute of geography and Resources Science Sichuan Normal University Chengdu 610101 China Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China key laboratory of Land Surface Pattern and Simulation CAS Beijing 100104 China Chongqing Jiaotong university Chongqing 400074 China

Using the Integrated Biosphere Simulator, a dynamic vegetation model, this study initially simulated the net primary productivity（NPP） dynamics of China＇s potential vegetation in the past 55 years（1961–2015） and in the future 3. years（2016–2050）. Then, taking the NPP of the potential vegetation in average climate conditions during 1986–2005 as the basis for evaluation, this study examined whether the potential vegetation adapts to climate change or not. Meanwhile, the degree of inadaptability was evaluated. Finally, the NPP vulnerability of the potential vegetation was evaluated by synthesizing the frequency and degrees of inadaptability to climate change. In the past 55 years, the NPP of desert ecosystems in the south of the Tianshan Mountains and grassland ecosystems in the north of China and in western Tibetan Plateau was prone to the effect of climate change. The NPP of most forest ecosystems was not prone to the influence of climate change. The low NPP vulnerability to climate change of the evergreen broad-leaved and coniferous forests was observed. Furthermore, the NPP of the desert ecosystems in the north of the Tianshan Mountains and grassland ecosystems in the central and eastern Tibetan Plateau also had low vulnerability to climate change. In the next 3. years, the NPP vulnerability to climate change would reduce the forest–steppe in the Songliao Plain, the deciduous broad-leaved forests in the warm temperate zone, and the alpine steppe in the central and western Tibetan Plateau. The NPP vulnerability would significantly increase of the temperate desert in the Junggar Basin and the alpine desert in the Kunlun Mountains. The NPP vulnerability of the subtropical evergreen broad-leaved forests would also increase. The area of the regions with increased vulnerability would account for 27.5% of China.

关键词： climate change vulnerability potential vegetation net primary productivity IBIS China

Sediment change under climate changes and human activities in the Yuanjiang-Red River Basin

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Science Bulletin 2007年第S2期 164-171页

作者： HE DaMing~(1+) REN Jing~(1,2) FU KaiDao~1 LI YunGang~1 1 Asia International Rivers Center of Yunnan university,Kunming 650091,China 2 College of Tourism and geography Science,Yunnan normal university,Kunming 650092,China

Both the climate change and human activities are the major Influence factors to the sediment change In mountainous *** on the over 40 years' record,suspended sediment loads（SSL）change at the Manheo gauging station in the lower reaches of Yuanjiang River（upper Red River）.In this paper,the variation of the sediment and its drivers were analyzed through different methods such as synchronous data comparison,traditional correlation,linear regression,and Granger *** results show that （1）the general trend of the annual average sediment concentration（SSC）and SSL at Manheo station is increasing from the 1960s to the 1990s,and there is a quick change period after 1984;（2）the SSL and SSC at Manhao station,during different periods of the 1960s,1970s,1980s and 1990s,are 1.87,2.49, 3.12,3.63.kg/m3.and 28.7×10～6,40.3.10～6,44.1×10～6,60.3.10～6 t/a,respectively;（3.the correlation analysis end the Granger causality test proved that the climate changes in the catchment were the main driving factors to the sediment variation in the period of 1960s and 1990s,but the influence by the mountain- ous human actions on the sediment change is stronger than that by the local climate changes in the 1970s and 1980s;（4）the correlation between the sediment changes and the forest coverage change is negative,which further proves that the sediment changes are strongly affected by the human activities in the basin.

关键词： sediment change Granger causality test Yuanjiang River the Longitudinal Range-Gorge Region

Impacts of climate change and grazing intensity on soil organic carbon in alpine meadow

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Impacts of climate change and grazing intensity on soil orga...

2011 International Conference on Business Management and Electronic Information(BMEI 2011)

作者： Xiaojia Li 1 2 Xianzhou Zhang 1 Hongtao Jiang 3.Qinglong Ma 4 Zhenxi Shen 1 Yuzhi Fan 1 2 Wei Yan 1 2 1 key laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China 2 Graduate university of Chinese Academy of Science Beijing China 3.School of {3. Beijing normal university Beijing China 4 NO.2 Middle School of Xilingol League Xilinhot Inner Mongolia China

In this paper,soil organic carbon was simulated in the next 50 years with CENTURY model in different climate scenarios at Damxung alpine meadow *** result shows that temperature and precipitation are the main contributor to the changes of soil organic *** in temperature and precipitation can reduce the accumulation of soil organic carbon resulting in the release of soil *** results are consistent in three climate change scenarios （temperature and precipitation increasing,temperature increasing and precipitation unchangeable,temperature unchangeable and precipitation increasing）.The content of soil organic carbon decreased,only slightly difference in extent in the three *** intensity was also a main factor to affect soil organic carbon and the influence on soil organic fractions was different.

关键词： soil organic carbon climate change CENTURY model alpine meadow

Preparation of Mesoporous Carbon by Using Hydroxypropyl-β-cyclodextrin-based Silica andlts Catalytic Activity

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Preparation of Mesoporous Carbon by Using Hydroxypropyl-β-c...

有机合成创新—产业化的新动力——中国化学会全国第三届有机合成化学与过程学术讨论会

作者： Wang,Huichun~(a,b) Li,Baolin~(*,a) Li,Jiangtao~a Lin,Pei~a (a key laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, and School of Chemistry and Materials Science,Shaanxi normal {3.,Xi’ an 710062) (b College of Life and geography,Qinghai normal {3.,Xining 810008)

In the field of catalysis,as catalyst support or protonic acid catalyst by functionalized with certain oxygen-containing functional groups(e.g.,-SOH,and -COOH),the mesoporous carbons(MCs) have attracted considerable attention for their many advantages such as high surface area,large pore volume,well-tailored pore size,chemical inertness,and electrical conducting ***,Few cases of MC directly as catalysts have been reported.

关键词： hydroxypropyl-β-cyclodextrin silica catalytic activity p-nitrotoluene hydrazine hydrate