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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 830011, 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

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 chen *a,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 830011, china b key laboratory of oasis ecology and desert environment, xinjiang institute of ecology and geography, chinese academy of sciences, urumqi 830011, 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

Carbon Dioxide Fluxes and Concentrations in a Cotton Field in Northwestern china:Effects of Plastic Mulching and Drip Irrigation

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Pedosphere 2011年第2期21卷 178-185页

作者： li Zhi-Guo key laboratory of oasis ecology and desert environment Xinjiang Institute of Ecology and Geography Chinese Academy ofSciences Urumqi 830011 (China) Graduate University of chinese academy of sciences Beijing 100049 (China) institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) Earth System Science Interdisciplinary Center University of Maryland College Park MD 20740 (USA)

In northwestern china, there has been a change from traditional cultivation system （TC） with no mulching and flood irrigation to a more modern cultivation system （MC） using plastic film mulching with drip irrigation. A field study was conducted to compare soil ＇C02 concentrations and soil surface COs fluxes between TC and MC systems during a cotton growing season. CO2 concentrations in the soil profile were higher in the MC system （3107-9212μL L-1） than in the TC system （1 275-8994 μL L-1） but the rate of CO2 flux was lower in the MC system. Possible reasons for this included decreased gas diffusion and higher soil moisture due to the mulching cover in the MC system, and the consumption of soil CO2 by weathering reactions. Over the whole cotton growing season, accumulated rates of CO2 flux were 300 and 394 g C m-2 for the MC and TC systems, respectively. When agricultural practices were converted from traditional cultivation to a plastic film mulching system, soil CO2 emissions could be reduced by approximately 100 g C m-2 year-1 in agricultural lands in arid and/or semi-arid areas of northern and northwestern china.

关键词： agricultural practice carbon cycle greenhouse gas emission soil respiration weathering reaction

Seasonal variation of soil respiration under different land use/land cover in arid region

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Science china Earth sciences 2007年第S1期 76-85页

作者： ZHANG liHua1,2, chen yaning1, li weihong1 & ZHAO RuiFeng1,2 1 key laboratory of oasis ecology and desert environment, xinjiang institute of ecology and geography, chinese academy of sciences, ürümqi 830011, china 2 Graduate University of chinese academy of sciences, Beijing 100049, china

Through combining the soil respiration with the main environmental factors under the planting shelterbelt (Populus woodland) and the natural desert vegetation (Tamarix ramosissima+Phragmites communis community and Haloxylon ammodendron community) in the western Junngar Basin, the difference in soil respiration under different land use/land cover types and the responses of soil respiration to temperature and soil moisture were analyzed. Results showed that the rate of soil respiration increased with temperature. During the daytime, the maximum soil respiration rate occurred at 18:00 for the Populus woodland, 12:00 for T. ramosissima+Ph. communis community, and 14:00 for H. ammodendron community, while the minimum rate all occurred at 8:00. The soil respiration, with the maximum rate in June and July and then declining from August, exhibited a similar trend to the near-surface temperature from May to October. During the growing season, the mean soil respiration rates and seasonal variation differed among the land use/land cover types, and followed the order of Populus woodland >T. ramosissima+Ph. communis community > H. ammodendron community. The difference in the soil respiration rate among different land use/land cover types was significant. The soil respiration of Pouplus woodland was significantly correlated with the near-surface temperature and soil temperature at 10 cm depth (P linearly correlated with the near-surface temperature and soil surface temperature (P < 0.01). Based on the near-surface tempera-ture, the calculated Q10 of Populus woodland, T. ramosissima+Ph. communis community and H. ammodendron community were 1.48, 1.59 and 1.63, respectively. The integrated soil respiration of the three land use/land cover types showed a significant correlation with the soil moisture at 0―5 cm, 5― 15 cm and 0―15 cm depths (P < 0.01). The quadr

关键词： soil respiration diurnal variation seasonal variation land use/land cover temperature soil moisture

基于SSM的伊犁河流域主导产业选择定量化研究

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山地学报 2010年第2期28卷 199-205页

作者：陈忠升陈亚宁李卫红陈亚鹏中国科学院新疆生态与地理研究所/中国科学院绿洲生态与荒漠环境重点实验室中国科学院研究生院

在梳理了传统主导产业选择基准理论与偏离-份额分析法基本原理的基础上,选取伊犁河流域1997年和2006年两个时间点的30个工业部门为分析对象,以国家范围内的30个工业部门的情况为参照,对研究区30个工业部门进行了份额偏离分量、结构偏离... 详细信息

在梳理了传统主导产业选择基准理论与偏离-份额分析法基本原理的基础上,选取伊犁河流域1997年和2006年两个时间点的30个工业部门为分析对象,以国家范围内的30个工业部门的情况为参照,对研究区30个工业部门进行了份额偏离分量、结构偏离分量和竞争力偏离分量的综合比较分析。结果表明,农副食品加工业、纺织业以及电力、热力的生产和供应业3个产业部门最有可能成为主导产业;同时,也说明研究方法具有基本客观性、有效性和较强的操作性。

关键词：偏离-份额分析法伊犁河流域主导产业选择

Suitable scale of Weigan River plain oasis

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Science china Earth sciences 2007年第S1期 56-64页

作者： HU ShunJun1,2, SONG YuDong1, TIAN ChangYan1, li YueTan1,4, li XiuCang1,4 & chen XiaoBing3 1 key laboratory of oasis ecology and desert environment, xinjiang institute of ecology and geography, chinese academy of sciences, ürümqi 830011, china 2 key laboratory for Agricultural Soil and Water Engineering in Arid Areas of Ministry of Education, yangling 712100, china 3 institute of Soil Science, chinese academy of sciences, Nanjing 210008, china 4 Graduate University of chinese academy of sciences, Beijing 100049, china

desert coexists with oasis in long time, and the existence and development of oasis system demand better oasis vegetation ecological system. oasis scale of arid zone plain encircling water should be determined in case of desertification caused by land over-reclamation under the circumstance of water resources shortage. Steady oasis with virtuous circle must have appropriate land use structure for agriculture, forestry and graziery. The study on the suitable scale and developmental space of oasis will provide theoretical and applicable foundation for effective construction of oases. By analyzing the hydrothermal, water and soil balance, an optimal mathematical model has been established. Based on hydrometeorology data collected for years in Weigan River plain, and by the principle of water balance, a calculation has been made of the water resources for evapotranspiration and the optimal acreage of oasis and cultivated land, which shows that the water resources for evapotranspiration in the Weigan River plain oasis is 22.32×108 m3 and the optimal oasis acreage under the condition of conventional irrigation mode is 3716.06 km2, in which the suitable cultivated land acreage is 1564.79 km2. Under the condition of water-saving irrigation, the suitable oasis acreage is 5515.49 km2, in which the suitable cultivated land acreage is 2322.31 km2. The oasis area had reached 4123 km2, and the cultivated land acreage had reached 1507 km2 after the Agriculture Irrigation Drainage Water Project of World Bank Loan in Weigan River basin was finished in 1997. The oasis and cultivated land acreage will be more suitable, and the oasis scale can be enlarged moderately by means of water saving irrigation.

关键词： suitable size oasis scale hydro-thermal balance equilibrium of water and land Weigan River

Impacts of Climatic Change on River Runoff in Northern xinjiang of china over Last Fifty Years

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chinese Geographical Science 2010年第3期20卷 193-201页

作者： yang Yuhui chen yaning li weihong WANG Minzhong SUN Guili The key laboratory of oasis ecology and desert environment Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences Urumqi 830011 China School of Geographic Science and Tourism Normal University of Xinjiang Urumqi 830054 China Graduate University of the chinese academy of sciences Beijing 100049 China institute of desert and Meteorology China Meteorological Administration Urumqi 830002 China

The characteristics of climatic change and fiver runoff, as well as the response of fiver runoff to climatic change in the northern xinjiang are analyzed on the basis of the hydrological and meteorological data over the last 50 years by the methods of Mann-Kendall nonparametric test and the nonlinear regression model. The results show that： 1） The temperature and the precipitation increased significantly in the whole northern xinjiang, but the precipitation displayed no obvious change, or even a decreasing trend in the northern mountainous area of the northern xinjiang. 2） River runoff varied in different regions in the northern xinjiang. It significantly increased in the northern slope of the Tianshan Mountains and the north of the northern xinjiang （p = 0.05）, while slightly ificreased in the west of the northern xinjiang. 3） North Atlantic Oscillation （NAO） affects fiver runoff by influencing temperature and precipitation. The NAO and precipitation had apparent significant correlations with the fiver runoff, but the temperature did not in the northern xinjiang. Since the mid-1990s fiver runoff increase was mainly caused by the increasing temperature in the northern slope of the Tianshan Mountains and the north of the northern xinjiang. Increased precipitation resulted in increased fiver runoff in the west of the northern xinjiang.

关键词： climatic change river runoff Mann-Kendall test nonlinear regression model NAO northern xinjiang

Distribution of soil organic carbon under different vegetation zones in the Ili River Valley, xinjiang

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Journal of Geographical sciences 2010年第5期20卷 729-740页

作者： yang yuhai chen yaning li weihong chen Yapeng key laboratory of oasis ecology and desert environment Xinjiang Institute of Ecology and Geography CASUrumqi 830011 China

We analyzed and estimated the distribution and reserves of soil organic carbon under nine different vegetation conditions including alpine meadow, meadow steppe, typical steppe, desert steppe, and temperate coniferous forest and so on, in the Ill River valley, Xin- jiang according to data from field investigations and laboratory analyses in 2008 and 2009. The study results show that the soil organic carbon content in the Ili River valley varies with the type of vegetation. In the 0-50 cm soil horizon, the soil organic carbon content is the highest under the vegetation types of alpine meadow and meadow steppe, slightly lower under temperate coniferous forest and typical steppe, and the lowest under the intrazonal vegetation and desert vegetation types. The soil organic carbon content shows basically a tendency to decrease as soil depth increases under various vegetation types except in the case of the intrazonal vegetation. Similarly, the soil organic carbon density is the highest and varies little under the vegetation types of alpine meadow, meadow steppe and temperate coniferous forest, and is the lowest under the desert vegetation type. Both the soil organic carbon content and density in the topsoil of meadows in the Ili River valley are high, so pro- tecting meadows in the Ili River valley, and especially their topsoil, should be a priority so that the potential of change in soil organic carbon in the shallow soil horizon is reduced, and this means maintenance of the stability of the soil carbon pool.

关键词： vegetation grassland soil organic carbon Ili River Valley

Long-term Trend and Fractal of Annual Runoff Process in Mainstream of Tarim River

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chinese Geographical Science 2008年第1期18卷 77-84页

作者： XU Jianhua chen yaning li weihong DONG Shan key laboratory of Geographic Information Science Ministry of Education Shanghai 200062 China Department of geography East China Normal University Shanghai 200062 China The key laboratory of oasis ecology and desert environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

Based on the time series data from the Aral hydrological station for the period of 1958-2005,the paper re-veals the long-term trend and fractal of the annual runoff process in the mainstream of the Tarim River by using the wavelet analysis method and the fractal *** main conclusions are as follows:1)From a large time scale point of view,*** time scale of 16(24)years,the annual runoff basically shows a slightly decreasing trend as a whole from 1958 to *** the time scale is reduced to 8(23)or 4(22)years,the annual runoff still displays the basic trend as the large time scale,but it has fluctuated more obviously during the period.2)The correlation dimension for the annual runoff process is 3.4307,non-integral,which indicates that the process has both fractal and chaotic *** correlation dimension is above 3,which means that at least four independent variables are needed to describe the dynamics of the annual runoff process.3)The Hurst exponent for the first period(1958-1973)is 0.5036,which equals 0.5 approximately and indicates that the annual runoff process is in *** Hurst exponents for the second(1974-1989)and third(1990-2005)periods are both greater than 0.50,which indicate that the annual runoff process showed a long-enduring characteristic in the two *** Hurst exponent for the period from 1990 to 2005 indi-cates that the annual runoff will show a slightly increasing trend in the 16 years after 2005.

关键词： annual runoff, wavelet fractal Tarim River

Analysis on the change of water potential of Populus euphratica *** *** Jabl under different irrigation volumes in temperate desert zone

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chinese Science Bulletin 2010年第10期55卷 965-972页

作者： FU AiHong chen yaning li weihong key laboratory of oasis ecology and desert environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

The measurement of plant water potential is considered to be a direct approach to confirming the irrigation time in present irrigation *** this current study,two shelter forests species in the Junggar Basin (Central Asia),Populus euphratica and *** Jabl,were *** monitored leaf water potential (ψl),stem water potential (ψs) and soil water potential (ψsoil) under different irrigation *** characteristics of the variation in leaf and stem water potential (ψl and ψs) of *** and *** Jabl,as well as the impact of soil water potential (ψsoil) on the leaf and stem water potential (ψl and ψs) under different irrigation conditions were *** results showed the following.(1) With increased irrigation,the intensity of drought stress on *** and *** Jabl decreased.(2) The intensity of drought stress experienced was less for *** Jabl than for *** under the same irrigation conditions.(3) The more intense the drought,the less sensitive was *** Jabl,but the more sensitive was ***,and vice versa.(4) For the *** community the soil water potential (Ψsoil) at 60 cm depth responded to variation in irrigation more strongly than at 30 and 90 cm *** the *** Jabl community the soil water potential (ψsoil) in the shallow surface layer responded to irrigation variation more strongly than that in deep layers.(5) In the event of relatively sufficient soil water,predawn stem water potential (ψpds) of plant was a reasonable indicator reflecting soil water potential (ψsoil).(6) The water demand of *** and *** Jabl shelter forests can be met with different irrigation policies:large volume and less frequency for *** but small volume and more frequency for *** Jabl.

关键词：电位变化灌水量荒漠区胡杨作者温带