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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 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

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 830011,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

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 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

Impacts of Global Warming Perturbation on Water Resources in Arid Zone: Case Study of Kaidu River Basin in Northwest China

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Journal of Mountain Science 2011年第5期8卷 704-710页

作者： MUPENZI Jean de la Paix State Key Laboratory of desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences

The main goal of this study was to assess the long-term impacts of global warming perturbation on water resources of the Kaidu River Basin in Northwest China. Temperature, precipitation and hydrology data during the past 29 years from 1979 to 2007 were collected and analyzed using parametric and non-parametric methods, the connection between temperature and precipitation by the combination of grey correlation analysis method and the hypothesis testing for trend of climate change. The results show a high increase in temperature in the study area as well as an extreme and highly variable hydrological regime in this region, where flash floods can exceed the total runoff from a sequence of years. These variations may be due to the geographical location of the Kaidu River Basin in arid zone. It also reveals that precipitation has a much greater impact on stream flow than that of temperature. The development of new approaches was proposed as responses to climate change in this arid region.

关键词： Global warming Kaidu River Temperature Precipitations Stream flow

Carbon Storage and Vertical Distribution in Three Shrubland Communities in Gurbantünggüt desert,Uygur AutonomousRegion of xinjiang,Northwest China

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chinese Geographical Science 2012年第5期22卷 541-549页

作者： GONG Yanming 1 ,HU Yukun 1 ,FANG Fei 1 ,liU Yanyan 1 ,li Kaihui 1 ,ZHANG Guangming 2 (1.Key Laboratory of Biogeography and Bioresource in Arid Land,xinjiang institute of Ecology and Geography,chinese academy of sciences,Urumqi 830011,China 2.State Key Laboratory of Vegetation and Environmental Change, institute of Botany,chinese academy of sciences,Beijing 100093,China) Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing China

This study was carried out in the Gurbantünggüt desert,Uygur Autonomous Region of xinjiang,Northwest China in August,*** quantify the storage,contribution and vertical distribution patterns of plant biomass carbon (PBC)and soil organic carbon(SOC)in the study area,we investigated the carbon concentrations and its vertical distribution in three different desert shrubland communities dominated by Reaumuria soongorica,Haloxylon ammodendron+*** and Tamarix ramosissima+***,*** analyzed vertical distribution of root biomass carbon and soil carbon contents by excavating soil profiles for each dominated *** results show that SOC is considerably the larger carbon pool in the soil layers of 1.0-3.0 m(the mean value of three shrubland communities is 38.46%)and 3.0-5.0 m(the mean value is 40.24%).In contrast,70.74%of belowground biomass carbon storage in 0-1.0 m layer,and its content decrease with increasing soil *** Haloxylon ammodendron+R. soongorica shrubland community has the highest belowground biomass carbon among three selected communities. This study highlights the importance of SOC stored in deep soil layers(lower than 3.0 m from the surface)in arid shrubland communities in the global carbon *** addition,it provides the data support for revealing deep soil solid carbon potential,and offers scientific basis for the further research in the carbon cycle of terrestrial ecosystem.

关键词： shrubland community plant biomass carbon soil organic carbon vertical distribution Gurbantünggüt desert

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

Germination strategies of two halophytes in Salt desert of northwestern China

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Science China Earth sciences 2007年第S1期 115-121页

作者： li li & ZHANG XiMing xinjiang institute of Ecology and Geography, chinese academy of sciences. ürümqi 830011, China

The effects of temperatures and salinities on germination of two halophytes, Kalidium capsicum and Suaeda physophora in northwestern China, were tested, and their seed size and seed production were compared. It was found that seed of Suaeda physophora germinate under 10℃, even about 0℃, and at a wide temperature range of 10―30℃. It showed about 50% germination in the concentration up to 0.7 mol/L NaCl; optimum germination temperature of Kalidium capsicum was between 20℃ and 30℃. The concentration of less than 0.3 mol/L NaCl inhibited absolutely its germination. Germination recovery was observed when salinities were reduced and total germination percentage exceeded 90%. Seeds of Kalidium capsicum showed no loss of viability while Suaeda physophora an annual loss of viability of 75% at room temperature. Mean weight of seeds of Suaeda physophora was about 8.5 times of Kalidium capsicum, whereas the number of seeds of the latter was more than 20 times of the former. Suaeda physophora was observed to be dependent on periodic precipitation in germination and seedling growth. It suggests the evident trace of the species with zonation pattern. On the other hand, the germination of Kalidium capsicum was affected by unpredictable rain and inundation. This species might be a type without zonation patterns in halophytes. It was concluded that both species are halophytes, but they are established successfully by different adaptation strategies in the early stage of life history.

关键词： germination strategy halophytes salt desert Kalidium capsicum Suaeda physophora

A CMIP6-based assessment of regional climate change in the chinese Tianshan Mountains

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Journal of Arid Land 2024年第2期16卷 195-219页

作者： liU Xinyu li Xuemei ZHANG Zhengrong ZHAO Kaixin li Lanhai Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China National-Local Joint Engineering research Center of Technologies and Applications for National Geographic State Monitoring Lanzhou 730070China Gansu Provincial Engineering Laboratory for National Geographic State Monitoring Lanzhou 730070China State Key Laboratory of desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China research Center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumqi 830011China

Climate warming profoundly affects hydrological changes,agricultural production,and human *** and semi-arid areas of China are currently displaying a marked trend of warming and *** chinese Tianshan Mountains(CTM)have a high climate sensitivity,rendering the region particularly vulnerable to the effects of climate *** this study,we used monthly average temperature and monthly precipitation data from the CN05.1 gridded dataset(1961-2014)and 24 global climate models(GCMs)of the Coupled Model Intercomparison Project Phase 6(CMIP6)to assess the applicability of the CMIP6 GCMs in the CTM at the regional *** on this,we conducted a systematic review of the interannual trends,dry-wet transitions(based on the standardized precipitation index(SPI)),and spatial distribution patterns of climate change in the CTM during *** further projected future temperature and precipitation changes over three terms(near-term(2021-2040),mid-term(2041-2060),and long-term(2081-2100))relative to the historical period(1961-2014)under four shared socio-economic pathway(SSP)scenarios(i.e.,SSP1-2.6,SSP2-4.5,SSP3-7.0,and SSP5-8.5).It was found that the CTM had experienced significant warming and wetting from 1961 to 2014,and will also experience warming in the future(2021-2100).Substantial warming in 1997 was captured by both the CN05.1 derived from interpolating meteorological station data and the multi-model ensemble(MME)from the CMIP6 *** MME simulation results indicated an apparent wetting in 2008,which occurred later than the wetting observed from the CN05.1 in *** GCMs generally underestimated spring temperature and overestimated both winter temperature and spring precipitation in the *** and wetting are more rapid in the northern part of the *** the end of the 21st century,all the four SSP scenarios project warmer and wetter conditions in the CTM with multiple dry-wet ***,the rise in precipitation fails to counterbal

关键词： climate change Coupled Model Intercomparison Project Phase 6(CMIP6) global climate models(GCMs) shared socio-economic pathway(SSP)scenarios standardized precipitation index(SPI) chinese Tianshan Mountains

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