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Ecological and environmental explanation of microbiotic crusts on sand dune scales in the Gurbantonggut Desert, xinjiang

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Progress in Natural Science:Materials International 2005年第12期15卷 1089-1095页

作者： CHEN Yaning,LI Weihong,ZHOU Zhibing and LIU Jiazhen xinjiang institute of ecology and geography,chinese academy of sciences,Urumqi 83.011,china xinjiang institute of ecology and geography Chinese Academy of Sciences Urumqi 830011 China

results obtained from the field investigation and the analysis in laboratory show that many species of microbiotic crusts of lichens,mosses and algae develop extensively in the Gurbantonggut Desert,*** formation,species and distribution are closely related to the environmental conditions at the different positions of sand *** animalcule crusts develop mainly on the mobile or semi-mobile sand surface of dune tops,the alga crusts develop mainly at the upper to middle parts of dune slopes,the lichen crusts develop at middle and lower parts of dune slopes,and the moss crusts are mainly distributed at the lower part of dune slopes and the interdune *** species,thickness and developing degree of microbiotic crusts increase from the upper part to the middle and lower parts of dune slopes and the interdune lowlands,and an obvious contrast between the microbiotic crusts and the different species of plant communities *** development and differentiation of microbiotic crusts at the different positions of dunes are the ecological appearance and the natural selection of synthetic adaptability of the different microbiotic crust species to the local environmental conditions,and are closely related to the ecological conditions,such as the physiochemical properties of soils and stability of topsoil texture.

关键词： microbiotic crust sand done scales environmental explanation the Gurbantonggut Desert

Plausible impact of global climate change on water resources in the Tarim river Basin

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Science china Earth sciences 2005年第1期48卷 65-73页

作者： CHEN Yaning & XU Zongxue xinjiang institute of ecology & geography, chinese academy of sciences, Urumqi 83.011, china College of Environmental sciences, Beijing Normal University, Beijing 100875, china xinjiang institute of ecology & geography Chinese Academy of Sciences Urumqi China College of Environmental sciences Beijing Normal University Beijing China

Combining the temperature and precipitation data from 77 climatological stations and the climatic and hydrological change data from three headstreams of the Tarim river: Hotan, Yarkant, and Aksu in the study area, the plausible association between climate change and the variability of water resources in the Tarim river Basin in recent years was investigated, the long-term trend of the hydrological time series including temperature, precipitation, and streamflow was detected, and the possible association between the El Ni(n)o/Southern Oscillation (ENSO) and these three kinds of time series was tested. The results obtained in this study show that during the past years, the temperature experienced a significant monotonic increase at the speed of 5%, nearly 1℃ rise; the precipitation showed a significant decrease in the 1970s, and a significant increase in the1980s and 1990s, the average annual precipitation was increased with the magnitude of 6.8 mm per decade. A step change occurred in both temperature and precipitation time series around 1986, which may be influenced by the global climate change. Climate change resulted in the increase of the streamflow at the headwater of the Tarim river, but the anthropogenic activities such as over-depletion of the surface water resulted in the decrease of the streamflow at the lower reaches of the Tarim river. The study result also showed that there is no significant association between the ENSO and the temperature, precipitation and streamflow.

关键词： climate change, hydrological change, temperature, precipitation, streamflow, Tarim river.

Trend of urban system structure under the restriction of water and land resources in xinjiang

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chinese Science Bulletin 2006年第A1期51卷 179-188页

作者： ZHANG Xiaolei & LEIJun xinjiang institute of ecology and geography, chinese academy of sciences, Urumqi 83.011, china institute of Geographical Science and Natural resources research, chinese academy of sciences, Beijing 100101, china Graduate School, chinese academy of sciences, Beijing 100039, china xinjiang institute of ecology and geography Chinese Academy of Sciences Urumqi China institute of Geographical Science and Natural resources research Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China

根据在 xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 xinjiang 的大多数城市和镇在水资源的缺乏水资源... 详细信息

根据在 xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 xinjiang 的大多数城市和镇在水资源的缺乏水资源的废物是严肃的，特别在小镇上。megapolis 和中等城市的发展被有限陆地资源显然限制。尽管有扩展小城市和镇的相对大的空格，水和陆地资源的输出好处是低的。为了完成城市的系统的顺序的扩大，在 xinjiang 组织，在都市化的快速的发展拿一个圆和三条带和节俭资源的策略的城市的空间发展模式被建议。

关键词：城镇体系结构水资源土地资源供水能力新疆

Arbuscular mycorrhizal fungi infection in desert riparian forest and its environmental implications: A case study in the lower reach of Tarim river

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Progress in Natural Science:Materials International 2008年第8期18卷 983-991页

作者： Yuhai Yang, Yaning Chen *, Weihong Li Key Laboratory of Oasis ecology and Desert Environment, xinjiang institute of ecology and geography, chinese academy of sciences, Urumqi 83.011, china Key Laboratory of Oasis ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

This study was conducted on the desert riparian forest along the lower reach of the inland Tarim river, which is located in the arid region of Northwest *** plant species in 10 families were collected from five monitoring sections,and examined for the infection of arbuscular mycorrhizal fungi (AMF). The impact of different soil factors on AMF infection rate and intensity was compared using the principal component analysis (PCA) method. The results indicate that 11 species are AM and only 4 are non-AM plants. The estimated capacity of AMF infection depends on families of plants and also the parameters (infection rate, infection intensity, fungal spore density) used. The density of fungal spores was relatively higher in Phragmites communis and Populus euphratica in Graminaceae and Salicaceae families, *** infection rate was above 50%in all the AM plants,except Calligonum *** highest infection rate appeared in Alhagi sparsifolia (97%) and Glycyrrhiza inflata (92%). However, when compared by AMF infection intensity, Tamarix spp. became the top one, followed by Alhagi sparsifolia, and Glycyrrhiza inflata was in the middle range of all the species. The PCA has identified that soil total salt, moisture, organic matter, total nitrogen, total P, available K and pH were closely associated with the AMF infection.

关键词： Arbuscular mycorrhiza Infection Ecological restoration Desert riparian forest Soil

Daily variation of carbon flux in soils of Populus euphratica forests in the middle and lower reaches of the Tarim river

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Progress in Natural Science:Materials International 2007年第5期17卷 584-590页

作者： Huang Xiang , Chen Yaning , Li Weihong , Ma Jianxin and Chen Yapeng (xinjiang institute of ecology and geography, chinese academy of sciences, Urumqi 83.011, china Graduate University, chinese academy of sciences, Beijing 100039, china) xinjiang institute of ecology and geography Chinese Academy of Sciences Urumqi 830011 China Graduate University Chinese Academy of Sciences Beijing 100039 China

In order to lucubrate the daily variation of respiration in soils of Populus euphratica forests and analyze its relationship with environmental factors in the middle and lower reaches of the Tarim river, the LI-8100 instrument of soil CO2 flux system was used to measure the parameters of soil carbon flux and air temperature 10 cm above ground surface along the profiles of Usyman, Archy river, Yengisu and Karday, and the relationships between the soil carbon flux and the soil moisture content were analyzed. The nonlinear regression analysis was carried out with the software SPSS13.0. We observed that: (1) soil respiration began to be restrained when the air temperature was up to 30℃10 cm above the ground surface; (2) the rates of soil respiration under the forests of Populus euphratica were significantly different at various moisture contents, the soil carbon flux was high along the Usyman profile, which has a high soil moisture content, and it was low along the profiles of Archy river, Yengisu and Karday, which has a low soil moisture content; (3) the exponential model can be used to explain the relationship between soil respiration and air temperature 10 cm above the ground surface. The average Q10 values along the profiles of Usyman, Archy river, Yengisu and Karday are 0. 61, 0.16, 0. 22 and 0. 35 respectively, much lower than the average of the world; (4) there is a positive correlation between the soil carbon flux and the soil moisture content.

关键词： Populus euphratica soil carbon flux air temperature 10 cm above ground surface soil moisture content the Tarim river.

Impact Assessment and Protection of Outstanding Landscape Integrity in a Natural Heritage Site:Fairy Valley,Kanas Nature reserve,xinjiang,china

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Journal of Mountain Science 2011年第1期8卷 46-52页

作者： HAN Fang1,2,YANG Zhaoping1,LIU Xinyu1,2,DI Feng3 1 xinjiang institute of ecology and geography,chinese academy of sciences,Urumqi 83.011,china 2 Graduate University of chinese academy of sciences,Beijing 100049,china 3.xinjiang Department of Science and Technology,Urumqi 83.011,china xinjiang institute of ecology and geography Chinese Academy of Sciences Urumqi China Graduate University of chinese academy of sciences Beijing China xinjiang Department of Science and Technology Urumqi China

The essential purpose of the Convention Concerning the Protection of World Cultural and Natural Heritage is to protect the integrity of heritage *** landscape is the core embodiment of the aesthetic value of a natural heritage *** paper proposes a new assessment method from the point of view of the protection of heritage *** is used to measure the degree of outstanding landscape integrity under the human and natural impact in natural heritage *** paper employ three indices,a visual index of outstanding landscape,a harmony index of the artificial landscape and a disturbance index of damaged landscape,to measure the impact of landscape *** impact assessment model is based on a weighted combination of the three *** study site is the Fairy Valley,Kanas Nature reserve,xinjiang Uygur Autonomous region in northwest *** information employed is derived from field investigation and a Digital Elevation Model(DEM).A comprehensive evaluation of the Fairy valley was undertaken and it was determined that the outstanding landscape values are being *** protection methods are proposed to reduce the adverse effects and maintain landscape quality,thereby providing site managers with suggestions for the protection of natural heritage *** broadly,the paper contributes novel methods of landscape assessment applicable to natural protected areas.

关键词： Landscape integrity Landscape impact assessment Landscape protection Natural heritage site Kanas Nature reserve xinjiang

Climate instability in the Yili region, xinjiang during the last glaciation

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chinese Science Bulletin 2000年第17期45卷 1604-1609页

作者： YE Wei, DONG Guangrong, YUAN Yujiang & MA Yingjie1. xinjiang institute of ecology and geography, chinese academy of sciences, Urumqi 83.011, china 2. Department of geography, Zhejiang Normal University, Jinhua 321004, china 3. institute of Desert research, chinese academy of sciences, Lanzhou 730000, china 4. xinjiang institute of Meteorological research, Urumqi 830002, china xinjiang institute of ecology and geography Chinese Academy of Sciences Urumqi China Department of geography Zhejiang Normal University Jinhua China institute of Desert research Chinese Academy of Sciences Lanzhou China xinjiang institute of Meteorological research Urumqi China

The climate is influenced by westerlies year in year out and the aeolian loess is widespread in the Yili region, the xinjiang Uygur Autonomous region. Through the study of the loess section with a thickness of 21.5 m, much useful information about climatic change in this region during the last glaciation was gotten. Grain size analysis of loess samples in the section showed that the climatic change in the Yili region was of instability during the last glaciation and similar to those of the North Atlantic Ocean and Greenland. In correspondence with the Heinrich events, the percentage of the size fraction of loess with grain size less than 10 μm decreased in cold stadials in the Yili region. This result suggests that the westerly wind be strengthened during the cold periods. Compared with the stadials, the content of the loess with grain size less than 10 μm was increased in interstadials, which indicated that the strength of the westerly wind was weakened. It is obvious that the climate was instable

关键词： Yili region last glaciation climate instability.

Photosynthesis of Populus euphratica and its response to elevated CO2 concentration in an arid environment

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Progress in Natural Science:Materials International 2009年第4期19卷 443-451页

作者： Honghua Zhou a,b,c, Yaning Chena,b, Weihong Li a,b, Yapeng Chen a,b, Lixin Fud a xinjiang institute of ecology and geography, chinese academy of sciences, 818 South Beijing road, Urumqi, xinjiang 83.011, china b Key Laboratory of Oasis ecology and Desert Environment, xinjiang institute of ecology and geography, chinese academy of sciences, Urumqi 83.011, china c Graduate School of chinese academy of sciences, Beijing 100039, china d College of Natural resources and Environment Science of xinjiang Agricultural University, Urumqi 830052, china xinjiang institute of ecology and geography Chinese Academy of Sciences 818 South Beijing Road Urumqi Xinjiang 830011 China Key Laboratory of Oasis ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Graduate School of chinese academy of sciences Beijing 100039 China College of Natural resources and Environment Science of xinjiang Agricultural University Urumqi 830052 China

The photosynthetic characterization of Populus euphratica and its response to the elevated carbon dioxide concentration ([CO2]) were analyzed based on its net photosynthetic rate (Pn), stomatal conductance (gs), intercellular CO2 concentration (Ci), transpiration rate (Tr), and water use effciency (WUE) at different groundwater depths measured by a portable gas exchange system (LI-6400) in the lower reaches of the Tarim river. The results showed that the elevation of [CO2] decreased the gs, and increased the Pn, Ci and WUE of P. euphratica. However, the effects of the elevated [CO2] on gs, Pn, Ci and WUE varied considerably with groundwater depth. The response of photosynthesis to rising [CO2] was stronger at the greater groundwater depth (more than 6 m) than that at the shallower groundwater depth (less than 6 m). The critical groundwater depth required to maintain the normal survival of P. euphratica was less than 6 m. When the groundwater depth increased to more than 6 m, P. euphratica encountered moderate water stress, and the plant suffered severe water stress when the groundwater depth increased to more than 7 m.

关键词： Photosynthesis Populus euphratica Groundwater depth CO2 concentration The lower reaches of the Tarim river

THE HYDrOLOGICAL EFFECT UNDEr HUMAN ACTIVITIESIN THE INLAND WATErSHEDS OF xinjiang, china

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chinese Geographical Science 2001年第1期11卷 27-34页

作者： LI Xin, JI Fang, ZHOU Hong-fei (xinjiang institute of ecology and geography, the chinese academy of sciences, Urumqi 83.011, P. K china) xinjiang institute of ecology and geography the Chinese Academy of Sciences Urumqi P. R. China

Natural environment, inland water distribution and water circulation has been changed greatly affected by human activities in xinjiang, china. Human activities developed quickly in the inland watersheds in xinjiang after 1950. More than 50% of river water is drawn into irrigation area, and all water in parts of little river is drawn to canal or reservoirs. However, there is evident hydrological effect caused by human activities. 1) water distribution in arid land has changed. A lot of river water is drawn into oasis and water table inside of oasis has risen but declined out of oasis. However, water table has declined in some cities because of over pumping for groundwater. 2) Stream process has changed after water drawing and drainage for irrigation. runoff in the lower reaches of river has generally decreased, and the lower reaches of some rivers are even disappeared for stream. 3) Large watersheds have been divided into several small watersheds. In some tributaries, most of the river water has drawn to irrigation area so that stream in the lower reaches has disappeared for years. 4) Evaporation at oasis has increased from 50–200mm/a to 800–1300mm/a after reclamation. But it decreased to 50mm/a or less out of oasis. Some lakes have reduced or dried. Water-system with canals and reservoirs has appeared in the oases. 5) Water quality of inland rivers and lakes has generally deteriorated because it accepts drainage water from farmland and factories. 6) Effective scale of human activities on hydrological process in arid land has expanded from separate rivers to all watersheds; from surface water to groundwater; from drought season to flood season; and from single year to several years. Scale of the effect of human activities to hydrological process is going larger and larger. Along with the effective usage of water resources in the inland watershed in xinjiang, the hydrological effect of human activities will be mainly change to: 1) river in pain area will be canalized;

关键词： xinjiang inland rivers human activities hydrological effects