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Responses of distribution pattern of desert riparian forests to hydrologic process in Ejina oasis

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Science china Earth {1. 2004年第z1期47卷 21-31页

作者： ZHAO Wenzhi, CHANG Xueli & HE ZhibinLinze Inland River Basin Comprehensive research Station, {1. and {2. regions environmental and engineering research Institute, chinese academy of sciences, lanzhou 730000, china Yantai Normal University, Yantai 2.4005, china 1. Linze Inland River Basin Comprehensive research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China2. Yantai Normal University 264005 Yantai China

By using the theories and methods of landscape ecology and the technology of GIS and RS, a study has been carried out on the responses of distribution pattern of desert riparian forest to hydrologic process on the basis of the hydrologic data from 1.90 to 2.00 and the TM image of 2.01.year. The results showed that: (1. there appears an even distribution pattern for the relative forest area in oasis, however, the degenerated forest diaplays an increasing tendency from west to east; (2. the desert riparian forest in Ejina is in completely degenerated process at the patch scale; (3) the number of patch is influenced not only by hydrologic process,but also by agricultural activity such as cultivation. The severe deterioration of the degraded vegetation in whole oasis initiates from lower reaches, and gradually impels to upstream; the fragmentation of landscape in the terminal site is more obvious, which is influenced by river shape and decreasing flux of water. It is found that the influence of surface hydrologic process to the ground hydrologic process of desert riparian forest in Ejina oasis is little for the recent ten years. The relative area of the degenerated forest increased with increasing ground water depth in the direction of parallel to river channel. On the contrary, in the direction perpendicular to river channel, there is a decreasing tendency for the average patch area of the forest and the degenerated forest with increasing ground water depth.

关键词： Ejina oasis, desert riparian forests, vegetation pattern, hydrologic process.

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science china Earth {1. 2005年第4期48卷 576-584页

作者： YAN Yuping1,2. KANG Shichang2.3,5, SUN Junying4,5, Paul A. Mayewski2.& QIN Dahe5 1. National Climate Center, china Meteorological Administration, Beijing 100081, china 2. Climate Change Institute, University of Maine, Orono, ME 04469, USA 3. Institute of Tibetan Plateau {2., chinese academy of sciences, Beijing 100085, china 4. chinese academy of Meteorological sciences, Beijing 100081, china 5. Key Laboratory of Ice Core and cold regions Environment, cold and {12. environmental and engineering {2. Institute, chinese academy of sciences, lanzhou 730000, china 1. National Climate Center China Meteorological Administration 100081 Beijing China 2. Climate Change Institute University of Maine 04469 Orono ME USA 3. Institute of Tibetan Plateau research Chinese Academy of Sciences 100085 Beijing China 4. Key Laboratory of Ice Core and cold {1. Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China 5. chinese {1. of Meteorological {2. 100081 Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 2.D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 2.D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (2.D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

Progress in studies of the climate of humid period and the impacts of changing precession in early-mid Holocene

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Progress in Natural Science:Materials International 2008年第12期18卷 1459-1464页

作者： Jianbin Huang~a Shaowu Wang~a Xinyu Wen~a Bao Yang~b a Department of Atmospheric sciences,School of Physics,Peking University,Beijing 100871,china b Laboratory for Desert and Desertification,{2. and arid regions environmental and engineering research Institute,chinese academy of sciences,lanzhou {12.,china [a]Department of Atmospheric sciences School of Physics Peking University Beijing 100871 China [b]Laboratory for Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Studies on the climate of humid period and the impacts of changing precession in the early-mid Holocene are reviewed in this paper. High-resolution proxy data indicated that the African Humid Period,strong summer monsoon from the Arabian Sea to South Asia, northward migration of ITCZ (lntertropical Convergence Zone) over the northern South America,and the humid period of china appeared in 1..5-5.5 kaBP,1..0-6.0 kaBP,1..5 5.4 kaBP,and 1..0-8.0 kaBP,*** studies proved that summer inso- lation over the Northern Hemisphere increased following the changes of precession in the early Holocene,which increased the land-sea temperature contrasts,intensified the summer monsoon circulation in the Northern Hemisphere,and finally induced a humid climate over the area under the influence of summer ***,modeling results underestimated the increase of precipitation and the degree of northward extension of monsoon rain belt compared with palaeo-{1. *** discrepancies between the modeling results and the palaeo-{1. data may be associated with the changes of North Atlantic circulation,sea ice and veg- etation ***,climate of the humid period was not stable,in which several droughts were inlaid on centennial *** this review,perspectives for further studies of the climate change of the humid period in the early-mid Holocene are also proposed.

关键词： Holocene Humid period Precession Summer monsoon

Characteristics of ^(1.7)Cs deposition in steppe area

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chinese Science Bulletin 2002年第10期47卷 848-853页

作者： ZHANG Chunlai, ZOU Xueyong,DONG Guangrong, ZHANG Xinbao & QIN ZhiLaboratory of Blown Sand Physics and engineering, cold and {2. regions environmental and engineering research Institute, chinese academy of sciences, lanzhou 730000, china china Center of D Laboratory of Blown Sand Physics and engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China china Center of Desert {1. at Beijing Normal University Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education of China Beijing Normal University Beijing China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Institute of Modern Physics Chinese Academy of Sciences Lanzhou China

Soil wind erosion in the semiarid steppe area was studied using the 1.7Cs tracing technique. Comparisons of 1.7Cs deposition characteristics between different soil profiles indicated that slight aeolian activities occurred on sandy grasslands and semi-fixed dunes with erosion/deposition rates of less than 0.1.8 cm/a, whereas they were intense on semi-shifting dunes with erosion/deposition rates of higher than 1.35 cm/a.

关键词： 1.7Cs steppe soil wind erosion.

A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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Science china Earth {1. 2010年第5期53卷 763-772页

作者： CHEN BaiLian1,3, ZHANG RenHe2. SUN ShuFen1, BIAN LinGen2. XIAO CunDe4,2.& ZHANG TingJun5 1 Institute of Atmospheric Physics, chinese academy of sciences, Beijing 10002., china 2.{2. academy of Meteorological sciences, Beijing 100081, china 3 Graduate University of chinese academy of sciences, Beijing 100049, china 4 cold and arid regions environmental and {12. research Institute, chinese academy of sciences, lanzhou 730000, china 5 The National Snow and Ice Data Center, University of Colorado, Boulder, CO 80309-0449, USA 1. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Chinese Academy of Meteorological Sciences Beijing 100081 China4. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China5. The National Snow and Ice Data Center University of Colorado Boulder CO 80309-0449 USA

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°2.′S, 70°2.′E), we applied the model to simulate the seasonal temperature variation within a depth of 2. m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1. 1. 3, 1. m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1. the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2. the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

Spatial distribution of 1.m firn temperature in the Antarctic Ice Sheet

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Science china Earth {1. 2011年第5期54卷 655-666页

作者： WANG YeTang1,3 & HOU ShuGui2.3 1 Shandong Marine Fisheries research Institute,Yantai 2.4006,china 2.MOE,Key Laboratory for Coast and Island Development,School of Geographic and Oceanographic {2.,Nanjing University,Nanjing 2.0093,china 3State Key Laboratory of Cryospheric Science,cold and arid regions environmental and engineering research Institute,chinese academy of {2.,lanzhou 730000,china 1. Shandong Marine Fisheries research Institute Yantai 264006 China3. State Key Laboratory of Cryospheric Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China2. MOE Key Laboratory for Coast and Island Development School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China

A database of Antarctic 1. m firn temperature was constructed using available borehole temperature measurements with data quality control to extend knowledge of Antarctic climate. Slopes from a high-resolution digital elevation model and the main ice divide were used to delineate main drainage sectors across Antarctica. In each drainage sector, a quantitative relationship between temperature and latitude, longitude and altitude was established using available tim temperature data. Quantitative relationships incorporating other factors affecting Antarctic air temperature such as atmospheric circulation and small-scale to- pography were used to derive a 1.-km resolution grid map of surface temperature. The resulting temperature patterns presented a reasonable depiction of both large and small-scale variations in Antarctic 1. m firn temperature. This map is useful for many spatial variation studies, Antarctic ice sheet models, and comparison with satellite-derived temperature data and outputs of atmospheric general circulation models.

关键词： Antarctica 1. m firn temperature spatial distribution

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 2.0014, china 2.cold and {2. regions environmental and engineering research Institute, chinese Academic of sciences, lanzhou, 730000, china College of Population Resources and Environment Shandong Normal University Jinan 250014 China cold and {1. {2. 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

The Impacts of Permafrost Change on NPP and Implications:A Case of the Source regions of Yangtze and Yellow Rivers

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Journal of Mountain Science 2011年第3期8卷 437-447页

作者： FANG Yiping QIN Dahe DING Yongjian YANG Jianping XU Keyan Institute of Mountain Hazards & Environment Chinese Academy of Sciences Chengdu 610041 China cold and {1. {2. environmental and engineering research Institute Chinese Academy of Sciences Lanzhou 730000 China Graduate School of chinese academy of sciences Beijing 100049 China

This paper studies the relationship between net primary productivity (NPP) and annual average air temperature (GT) at 0cm above ground in permafrost regions by using revised Chikugo NPP model,cubic spline interpolating functions,and non-linear regression *** source regions of the Yangtze and Yellow Rivers were selected as the {2. *** illustrate that:(1. There is significant non-linear relationship between NPP and GT in various typical years;(2. The maximum value of NPP is 6.1.,5.87,7.73,and 5.41.DM·t·hm-2.·a-1.respectively,and the corresponding GT is 7.1.1..0,2..2.and 8.9 o C respectively in 1.80,1.90,2.00 and 2.07;(3) In 1.80,the sensitivity of NPP to GT is higher than in 1.90,2.00 and *** tendency shows that the NPP presents change from fluctuation to an adaptation process over time;(4) During 1.80～2.07,the accumulated NPP was reduced to 8.05,and the corresponding carrying capacity of theoretical livestock reduced by 1.%;(5) The shape of the demonstration region of ecological compensation system,livelihood support system,and science appraisal system in the source regions of Yangtze and Yellow Rivers are an important {2. for increasing the adaptation capacity and balancing protection and development.

关键词： The source regions of Yangtze and Yellow Rivers Permafrost Ground temperature (GT) Net primary productivity (NPP) Policy adaptation

Grain size record of microparticles in the Muztagata ice core

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Science china Earth {1. 2006年第1期49卷 10-17页

作者： WU Guangjian1,2. YAO Tandong1,2. XU Baiqin1,2. LI Zheng2. TIAN Lide1,2. DUAN Keqin2.& WEN Linke2.1. Laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau research, chinese academy of sciences, Beijing 100085,{2. 2. Key Laboratory of Cryosphere and Environment, Jointly Established by cold and arid regions environmental and Engi-neering research Institute and Institute of Tibetan Plateau research, chinese academy of sciences and chinese academy of Meteorological {12.,{2. Meteorological Administration, lanzhou 730000,{2. 1. Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China

The dust transport and sediment characteristics are discussed based onanalysis of mi-croparticle size and size distribution in the Muztagata ice core at 6350 m a.s.I. Thefiner particles with diameter of 1.5 μm are the dominant fraction in number, while middle andcoarse particles mainly contribute to the total volume. The lognormal distribution characteristicscan be seen for some high concentration samples, showing that model size and standard variation aregreater than that in the Greenland ice cores. However, size-volume distribution of some lowconcentration samples is abnormal. Those distributions reflect the dust deposit process in highmountain glaciers at mid-low latitudes and show differences from those in polar ice sheet.

关键词： Muztagata, ice core, microparticle, dust, size distribution.