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土地沙漠化过程的土壤风蚀率指标——以青海共和盆地为例

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水土保持学报 2003年第4期17卷 90-93页

作者：张春来邹学勇董光荣北京师范大学中国沙漠研究中心教育部环境演变与自然灾害重点实验室北京100875 中国科学院寒区旱区环境与工程研究所兰州730000

由风蚀所导致的土壤物质再分配过程,决定了土地沙漠化的程度。根据半干旱干草原地区不同程度沙漠化土地土壤风蚀率的137Cs示踪结果,沙漠化各个阶段的土壤风蚀率指标为:潜在沙漠化土地以微弱堆积和微度风蚀为特征,风蚀率小于2000kg/(hm2... 详细信息

由风蚀所导致的土壤物质再分配过程,决定了土地沙漠化的程度。根据半干旱干草原地区不同程度沙漠化土地土壤风蚀率的137Cs示踪结果,沙漠化各个阶段的土壤风蚀率指标为:潜在沙漠化土地以微弱堆积和微度风蚀为特征,风蚀率小于2000kg/(hm2·a);轻度沙漠化土地风蚀率介于2000～7000kg/(hm2·a)之间;中度沙漠化土地风蚀率大于7000kg/(hm2·a);重度沙漠化土地风蚀和堆积都很强烈,地表物质交换迅速,没有必要制定风蚀指标。

关键词：土地沙漠化土壤风蚀风蚀率指标青海共和盆地半干旱干草原地区

Effect of Landform on Seasonal Temperature Structures across china in the Past 52 Years

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Journal of Mountain Science 2006年第2期3卷 158-167页

作者： LU Aigang PANG Deqian GE Jianping HE Yuanqing PANG Hongxi YUAN Lingling Institute of Geography Research Weinan Teachers College Weinan 714000 Shaanxi China ministry of education key laboratory for Biodiversity Science and Engineering College of Life SciencesBeijing Normal University Beijing 100875 China Cold and Arid Regions environmental and Engineering Institute Chinese Academy of Sciences Lanzhou 730000China

The data of 16o national meteorological observatory stations including the long-term monthly temperature data in china were analyzed to study the seasonal variation of the spatial temperature structures across china in the past half century. It is found that temperature structures differ between seasons： a latitude temperature pattern in winter and a landform temperature pattern in summer, which indicate that the effect of landform on temperature structure is much stronger in summer than that in winter and the effect of latitudinal temperature is much stronger in winter than that in summer. The mechanisms of the seasonal difference in temperature structures are also discussed in this paper.

关键词： Landform effect latitude effect seasonal variation temperature structure climate change mechanism china

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黄河流域坡高地系统最小生态需水研究

山地学报 2004年第2期22卷 154-160页

作者：张远杨志峰北京师范大学环境学院北京师范大学环境学院水环境模拟国家重点实验室水沙科学教育部重点实验室北京 100875 中国环境科学研究院北京 100012水环境模拟国家重点实验室水沙科学教育部重点实验室北京 100875

以保护和恢复流域坡高地生态系统为目的,对坡高地最小生态需水问题进行研究,提出了坡高地生态需水和生态缺水的计算方法。以黄河流域为实例,在GIS和遥感技术支持下对坡高地最小生态需水量和缺水量进行了计算,并从时空两个尺度揭示了黄... 详细信息

以保护和恢复流域坡高地生态系统为目的,对坡高地最小生态需水问题进行研究,提出了坡高地生态需水和生态缺水的计算方法。以黄河流域为实例,在GIS和遥感技术支持下对坡高地最小生态需水量和缺水量进行了计算,并从时空两个尺度揭示了黄河流域坡高地生态系统最小生态需水的变化规律,研究成果可为流域生态环境建设和水资源合理配置提供依据。

关键词：生态需水坡高地系统时空变化黄河流域

Pollen assemblage characteristics of lakes in the monsoon fringe area of china

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Chinese Science Bulletin 2008年第4期53卷 3354-3363页

作者： TIAN Fang1,2,XU QingHai1,2,3,LI YueCong1,2,CAO XianYong1,2,WANG XueLi1,2 & ZHANG LiYan1,2 1 College of Resources and environmental Sciences,Hebei normal university,Shijiazhuang 050016,china 2 Hebei key laboratory of environmental change and Ecological Construction,Shijiazhuang 050016,china 3 key laboratory of Western china’s environmental System(ministry of education),Lanzhou university,Lanzhou 730000,china College of Resources and environmental Sciences Hebei Normal University Shijiazhuang 050016 China Hebei key laboratory of environmental change and Ecological Construction Shijiazhuang 050016 China key laboratory of Western china’s environmental System (ministry of education) Lanzhou University Lanzhou 730000 China

This paper presents the pollen assemblages from 108 surface sediment samples from 4 lakes(the Lake Daihai,Lake Hongjiannao,Lake Hulunnao and Lake Duikounao) in the monsoon fringe area of *** herb pollen taxa Artemisia,Chenopodiaceae,Poaceae and Compositae are the major components of pollen assemblages of the 4 lakes and Pinus,Betula,Quercus,Ulmus,Populus,Ostryopsis and Elaeagnaceae are frequently presented,which reflect regional and local vegetation *** mean similarity coefficients for samples from the Lake Daihai,Lake Hongjiannao,Lake Hulunnao and Lake Duikounao are 0.66 ± 0.17,0.71 ± 0.11,0.73 ± 0.12 and 0.67 ± 0.12 respectively,so pollen assemblages are relatively consistent in each lake,which shows that focusing and mixing effects have occurred before and after pollen ***,pollen assemblages do differ between sampling sites in each *** largest difference is seen in the Lake Daihai,followed by the Lake Duikounao,Lake Hulunnao and Lake Hongjiannao(The mean Euclidean distance is 20.09 ± 11.11,11.22 ± 3.64,10.67 ± 4.03 and 8.44 ± 4.51 respectively).These differences are possibly caused by the differences of focusing and mixing effects,pollen source areas,drainage areas and regional vegetation *** Lake Daihai and Lake Hongjiannao have water deeper than 5 m and strong re-suspension,focusing and mixing effects occur in the lakeshore and shallow water areas,where pollen concentrations are lower than in deeper lake *** the Lake Hulunnao and Lake Duikounao,with depths less than 5 m,re-suspension and mixing effects are obvious across the whole lake area,so pollen assemblages and pollen concentra-tions are more consistent among sampling sites in each *** between the lake samples and samples from the inflowing river reveals that wind is primary pollen transportation force in the Lake Hongjiannao,where the consistency of pollen assemblage is conspicuous,while there is greater variation in lakes where pollen input is

关键词：湖泊花粉相似系数欧几里得季风

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Perturbed solution of sea-air oscillator for the El Nino/ La Nina-Southern Oscillation mechanism

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Acta Oceanologica Sinica 2009年第3期28卷 1-4页

作者： ZHOU Xianchun LIN Yihua WANG Hui MO Jiaqi College of Electronic and Information Engineering Nanjing University of information Science and Technology Nanjing 210044 China Division of Computational Science E-Institutes of Shanghai Universities at SJTU Shanghai 200240 China State key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China National Marine environmental Forecastins Center Beijing 100081 China Department of Mathematics Anhui Normal University Wuhu 241000 China

A class of coupled system of the E1 Nino/La Nina-Southern Oscillation （ENSO） mechanism is studied. Using the perturbed theory, the asymptotic expansions of the solution for ENSO model are obtained and the asymptotic... 详细信息

关键词： nonlinear perturbation theory E1 Nino/La Nina-Southern Oscillation model

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植被对土壤风蚀影响的风洞实验研究

水土保持学报 2003年第3期17卷 31-33页

作者：张春来邹学勇董光荣刘玉璋北京师范大学中国沙漠研究中心教育部环境演变与自然灾害重点实验室北京100875 中国科学院寒区旱区环境与工程研究所兰州730000

利用风洞模拟实验,系统研究了植被覆盖对土壤风蚀的影响。结果表明,临界侵蚀风速与植被盖度之间、风速与土壤风蚀发生的临界植被盖度之间均为非线性正相关关系;植被盖度与空气动力学粗糙度、摩阻速率之间具有良好的相关性;植被覆盖条件... 详细信息

利用风洞模拟实验,系统研究了植被覆盖对土壤风蚀的影响。结果表明,临界侵蚀风速与植被盖度之间、风速与土壤风蚀发生的临界植被盖度之间均为非线性正相关关系;植被盖度与空气动力学粗糙度、摩阻速率之间具有良好的相关性;植被覆盖条件下空气动力学粗糙度和摩阻速率的增大对土壤风蚀具有显著的影响。

关键词：植被覆盖土壤侵蚀风蚀风洞实验植被盖度空气动力学粗糙度摩阻速率

Effects of road networks on ecosystem service value in the Longitudinal Range-Gorge Region

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Science Bulletin 2007年第S2期 180-191页

作者： WANG Juan~(1,2) CUI BaoShan~(1+) LIU ShiLiang~1 DONG ShiKui~1 WEI GuoLiang~1 LIU Jie~1 1 Sate key Joint laboratory of environmental Simulation Pollution Control,School of Environment,beijing normal university,beijing 100875.china 2 china Non-ferrous Metals Resource Geological Survey,beijing 100021,china

Based on the land use(LU)(in 1985 and 2000)and road networks(RN)data in the Longitudinal Range- Gorge Region(LRGR),ecosystem services value(ESV)loss under the disturbance of road networks was estimated by using landscape degradation index(LDI)to clarify the effects of human activities on ecosystem service function(ESF).Results show that the ESV decreased more than 65×10～8 Yuan(RMB) due to the transformation of ecosystems in the study area during the pest 16 *** ecosystems influenced by road networks of different grades account for 5.4% of the total land in the study *** ecosystems lost their ESV of 1900×10～8 Yuan(RMB)by the disturbance of *** effect of RN on the ESV decreased *** forecast shows that ESV will be decreased 1.2%/a on average in 2010 and 2020 due to RN *** effect of ecosystem structure change on ESV was complex and *** disturbance of RN,one of the human activities influencing ESF is considered,further study end new method should be developed to accurately estimate the loss of ESV and the ecosystem function.

关键词： ecosystem service value road networks landscape degradation index Longitudinal Range-Gorge Region

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[( )-275(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 ([(28.4)( )]kyr~[(25.8)( )]kyr), Laschamp Event ([(43.3)( )]kyr^40.5 kyr), Gaotai Event (82.8 kyr~[(72.4)25( )]kyr) and the Blake Event (127.4 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)[(. )-250( )]Here,[( )-250( )]we tentatively[( )-250( )]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 Central Asia or even North Hemispheric high latitude regions.

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

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中国东北地区植被NDVI对气候变化的响应

生态学杂志 2009年第6期28卷 1041-1048页

作者：王宗明国志兴宋开山罗玲张柏刘殿伟黄妮任春颖国科学院东北地理与农业生态研究所长春130012 北京师范大学环境演变与自然灾害教育部重点实验室北京100875

结合1982—2003年GIMMS-NDVI数据集和GIS技术,应用基于像元的相关分析方法,分析了东北地区植被NDVI对气候变化的响应。结果表明:1)1982—2003年,东北地区年平均气温呈上升趋势,而年降水量呈下降趋势;东北地区植被NDVI与年平均气温呈显... 详细信息

结合1982—2003年GIMMS-NDVI数据集和GIS技术,应用基于像元的相关分析方法,分析了东北地区植被NDVI对气候变化的响应。结果表明:1)1982—2003年,东北地区年平均气温呈上升趋势,而年降水量呈下降趋势;东北地区植被NDVI与年平均气温呈显著正相关的像元占12.84%,主要分布在松嫩平原南部、三江平原中部和西辽河平原,植被类型为农田、阔叶林、草原。植被NDVI与年平均气温几乎不存在显著负相关性;植被NDVI与年降水呈显著和极显著正相关的像元比例为4.55%,主要植被类型为草原和农田;植被NDVI与年降水量呈显著负相关的像元比例为7.52%,主要植被类型为针叶林和阔叶林。2)东北地区植被与生长季气温显著正相关和显著负相关的比例分别为3.96%和4.35%;植被与生长季降水显著正相关和显著负相关的比例分别为8.81%和8.54%。3)东北地区58.21%的植被像元与春季气温显著或极显著正相关,主要分布在大兴安岭中部、小兴安岭、长白山及完达山-张广才岭等地区,主要植被类型为阔叶林、农田、针叶林和草甸;植被NDVI与春季气温几乎不存在显著负相关性。植被NDVI与春季降水呈显著正相关和显著负相关的比例分别为4.81%和1.67%。4)东北地区植被NDVI与夏季气温和降水呈显著相关的比例明显少于春季,与夏季气温正相关的比例为7.61%,与夏季降水显著负相关的比例为6.29%。秋季气温和降水对东北地区植被NDVI影响较小,其中植被NDVI与秋季气温显著正相关的像元占植被像元总数的6.05%,几乎不存在与秋季气温显著负相关的植被像元;植被NDVI与秋季降水显著负相关的比例为5.43%,几乎不存在与秋季降水显著正相关的植被像元。

关键词： NDVI 气温降水东北地区