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Characteristics of Wind Erosion and Deposition in Oasis-desert Ecotone in Southern Margin of Tarim Basin,China

Chinese Geographical Science 2014年第6期24卷 658-673页

作者： MAO Donglei LEI Jiaqiang ZENG Fanjiang RAHMUTULLA Zaynulla WANG Cui ZHOU Jie xinjiang Institute of Ecology and Geography Chinese Academy of Sciences University of Chinese Academy of Sciences College of Geographical Science and Tourism Xinjiang Normal University cele national station of observation and research for desert-grassland ecosystem in xinjiang

The oasis-desert ecotone is a fragile ecological zone that is affected both by oasis and desert conditions. To understand the impact of the differences in wind power, and the influence of wind erosion and deposition on the ecotone, meteorological data and con- temporaneous wind erosion and deposition data were collected on the southern margin of Tarim Basin with serious sand-blown hazards. The wind velocity, average wind velocity, sand drift potential （DP）, resultant sand drift potential （RDP）, and sand transportation rate decrease significantly and successively across four landscape types with increasing vegetation coverage （VC）. Flat surfaces and areas of shifting sandy ground experience intense wind erosion with fast movement of mobile sand dunes; semi-fixed sand areas experience ex- tensive wind deposition but only slight wind erosion; and fixed sand areas experience only slight wind erosion and deposition. Volume of wind erosion on bare newly reclaimed farmland is up to 6.96 times that of bare shifting sandy ground. Wind erosion volume per unit area and VC follow an exponential function relationship in natural conditions, while wind deposition volume per unit area does not conform to any functions which has close relationship with vary topography and arrangement patterns of vegetation besides for VC. The results indicate that the volume of wind erosion has a close correlation with VC, and different types and distribution patterns of topog- raphy and vegetation also profoundly influence the wind deposition volume in the field, and underground water tables in different land- scape types control the plant community distribution. Keywords： wind erosion; wind deposition; oasis-desert ecotone; vegetation coverage （VC）; topography; cele County

关键词： wind erosion wind deposition oasis-desert ecotone vegetation coverage (VC) topography cele County

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Relations between soil heterogeneity and common reed(Phragmites australis *** Steud.) colonization in the Keriya River Basin,xinjiang of China

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Journal of Arid Land 2014年第6期6卷 753-761页

作者： Lu GONG ChangJun LI Tashpolat TIYIP College of Resources and Environment Science Xinjiang University Key Laboratory of Oasis Ecology Ministry of Education xinjiang Institute of Ecology and Geography Chinese Academy of Sciences cele national station of observation & research for desert-grassland ecosystem in xinjiang

How common reed （Phragmites australis Trin. ex Steud.） colonization correlates to soil heterogeneity and environmental determinants remains unclear in arid areas. We conducted a field investigation and soil sampling in 100 plots along Keriya River Basin to uncover the relationship between common reed and heterogeneous soils. Reed colonization variables and its soil properties were measured and recorded for the analysis of their relationship using Pearson correlation and redundancy analysis methods. The comparison results of common reed characteris- tics among 100 plots showed that common reeds performed strong tolerance and ecophysiological plasticity to edaphic stresses. Common reed colonization was tightly connected to soil heterogeneity according to the correla- tion analysis between its colonization characteristics and soil properties. Common reed colonization got feedbacks on soil properties as well, including the increase of soil organic matter and the alleviation of salt uplifting. The main limiting environmental determinant of common reed colonization was soil salt, followed by pH and soil water content.

关键词： soil heterogeneity plant colonization common reed plasticity determinant

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Characteristics of Meteorological Factors over Different Landscape Types During Dust Storm Events in cele,xinjiang,China

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Journal of Meteorological research 2014年第4期28卷 576-591页

作者：毛东雷雷加强李生宇曾凡江王翠周杰 xinjiang Institute of Ecology and Geography Chinese Academy of Sciences University of Chinese Academy of Sciences College of Geographical Sciences and Tourism Xinjiang Normal University cele national station of observation and research for desert-grassland ecosystem in xinjiang

Landscape characteristics influence meteorological factors, thus affect the occurrence and nature of dust storm events. The present study investigates the spatiotemporal characteristics of six meteorological factors （wind velocity, wind direction, air temperature, relative humidity （RH）, photo synthetically active radiation （PAR）, and solar radiation） over different landscape types （shifting-sand frontier, semi-fixed sandy land, fixed sandy land, and the inner region of an oasis） before and after dust storms during four typical dust storm events in an oasis-desert ecotone in cele, xinjiang, China. The results show that the average wind velocity decreased significantly from the shifting-sand frontier to the inner oasis, which was mainly attributable to the vegetation coverage. Before the dust storm events, there were obvious differences in air temperature and RH either in the horizontal or vertical direction over the different landscape types. However, these factors were very similar during and following the dust storm events. PAR and solar radiation were significantly reduced during the dust storm events and the subsequent sand-blowing and floating-dust conditions. This effect was much stronger than during similar weather conditions without dust storm events such as sand-blowing and overcast and/or rainy days. Additionally, the variation in the meteorological factors among the different landscapes was also affected by the prevailing wind direction during the dust storm events. However, the landscape type slightly changed the prevailing wind direction, with the greatest dispersion distribution of wind direction in the inner oasis. The findings of this study are helpful for understanding the function of landscape types in the occurrence of dust storms, as well as for providing a theoretical basis for prevention of dust storms.

关键词： dust storms weather meteorological factors changing characteristics cele

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Root characteristics of Alhagi sparsifolia seedlings in response to water supplement in an arid region,northwestern China

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Journal of Arid Land 2013年第4期5卷 542-551页

作者： DongWei GUI FanJiang ZENG Zhen LIU Bo ZHANG State Key Laboratory of desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences cele national station of observation & research for desert-grassland ecosystem in xinjiang Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences

The effect of variation in water supply on woody seedling growth in arid environments remain poorly *** subshrub Alhagi sparsifolia Shap.（Leguminosae）,distributed in the southern fringe of the Taklimakan desert,xinjiang,northwestern China,has evolved deep roots and is exclusively dependent on groundwater,and performs a crucial role for the local ecological *** the cele oasis,we studied the responses of *** seedling roots to water supplement at 10 and 14 weeks under three irrigation treatments （none water supply of 0 m3/m2 （NW）,middle water supply of 0.1 m3/m2 （MW）,and high water supply of 0.2 m3/m2 （HW））.The results showed that the variations of soil water content （SWC） significantly influenced the root growth of *** *** leaf area,basal diameter and crown diameter were significantly higher in the HW treatment than in the other *** biomass,root surface area （RSA）,root depth and relative growth rate （RGR） of *** roots were all significantly higher in the NW treatment than in the HW and MW treatments at 10 ***,these root parameters were significantly lower in the NW treatment than in the other treatments at 14 *** SWC continued to decline as the experiment went on （until less than 8％ gravimetric SWC）,the seedlings still showed drought tolerance through morphological and physiological responses,but root growth suffered serious water stress compared to better water supply *** to our study,keeping a minimum gravimetric SWC of 8％ might be important for the growth and establishment of *** during the early growth *** results will not only enrich our knowledge of the responses of woody seedlings to various water availabilities,but also provide a new insight to successfully establish and manage *** in arid environments,further supporting the sustainable development of oases.

关键词： arid environment Alhagi sparsifolia roots irrigation treatments oasis

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Water use efficiency and yield responses of cotton to field capacity-based deficit irrigation in an extremely arid area of China

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International Journal of Agricultural and Biological Engineering 2019年第6期12卷 91-101页

作者： Haifeng Li Zhiming Qi Dongwei Gui Fanjiang Zeng State Key Laboratory of desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China School of Environmental and Land Resource Management Jiangxi Agricultural UniversityNanchang 330045China cele national station of observation&research for desert-grassland ecosystem in xinjiang Cele 848300XinjiangChina University of Chinese Academy of Sciences Beijing 100049China

The objectives of present investigation were to test the effects on water use efficiency(WUE)and cotton yield of implementing a range of deficit irrigation regimes triggered at specific fractions of root zone soil moisture,field capacity(θfc)and different crop phenological *** study was conducted on southern oasis of the Taklamakan desert,*** cotton crop’s WUE was quantified,as were leaf photosynthesis and *** a photosynthetic perspective,deficit irrigation resulted in 16.8%,10.3%and 2.2%increases in leaf WUE underθfc-based regulated deficit irrigation(T1,T2,and T3),compared to the control,*** yield and its components were significantly affected by irrigation depths(p≤0.05).A relatively high seed yield(0.65 kg/m3)and the highest WUE were achieved,under T3(70%θfc at seedling stage,60%θfc at squaring,50%θfc at full-bloom,70%θfc at boll,70%θfc at boll cracking stage),showing it to be the most effective and productive irrigation schedule *** the application ofθfc-based deficit irrigation in surface-irrigated cotton fields showed great potential in saving water,maintaining a high WUE,and improving cotton seed yield,a management strategy consisting or irrigation thresholds of 70%θfc in the root zone at the seedling,boll and boll cracking stages,and of 60%θfc at the squaring stage,and 50%θfc at the full-bloom stage,would be recommended for this extremely arid region.

关键词： regulated deficit irrigation evapotranspiration seed cotton yield water use efficiency Qira Oasis

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Responses of root growth of Alhagi sparsifolia Shap. (Fabaceae) to different simulated groundwater depths in the southern fringe of the Taklimakan desert, China

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Journal of Arid Land 2013年第2期5卷 220-232页

作者： FanJiang ZENG Cong SONG HaiFeng GUO Bo LIU WeiCheng LUO DongWei GUI Stefan ARNDT DaLi GUO State Key Laboratory of desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences cele national station of observation and research for desert-grassland ecosystem University of Chinese Academy of Sciences School of Forest and ecosystem Science University of Melbourne Institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences

Alhagi sparsifolia Shap. （Fabaceae） is a spiny, perennial herb. The species grows in the salinized, arid regions in North China. This study investigated the response characteristics of the root growth and the dis- tribution of one-year-old A. sparsifolia seedlings to different groundwater depths in controlled plots. The eco- logical adaptability of the root systems of A. sparsifolia seedlings was examined using the artificial digging method. Results showed that：（1） A. sparsifolia seedlings adapted to an increase in groundwater depth mainly through increasing the penetration depth and growth rate of vertical roots. The vertical roots grew rapidly when soil moisture content reached 3%-9%, but slowly when soil moisture content was 13%-20%. The vertical roots stopped growing when soil moisture content reached 30% （the critical soil moisture point）. （2） The morphological plasticity of roots is an important strategy used by A. sparsifolia seedlings to obtain water and adapt to dry soil conditions. When the groundwater table was shallow, horizontal roots quickly expanded and tillering increased in order to compete for light resources, whereas when the groundwater table was deeper, vertical roots developed quickly to exploit space in the deeper soil layers. （3） The decrease in groundwater depth was probably respon- sible for the root distribution in the shallow soil layers. Root biomass and surface area both decreased with soil depth. One strategy of A. sparsifolia seedlings in dealing with the increase in groundwater depth is to increase root biomass in the deep soil layers. The relationship between the root growth/distribution of A. sparsifolia and the depth of groundwater table can be used as guidance for harvesting A. sparsifolia biomass and managing water resources for forage grasses. It is also of ecological significance as it reveals how desert plants adapt to arid environments.

关键词： Alhagi sparsifolia Shap. simulated groundwater depth root system growth and distribution ecological adaptability root morphological plasticity

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Effects of parasitic plant Cistanche deserticola on chlorophyll a fluorescence and nutrient accumulation of host plant Haloxylon ammodendron in the Taklimakan desert

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Journal of Arid Land 2012年第3期4卷 342-348页

作者： Li LI XinWen XU YongQiang SUN WeiHAN PengFei TU cele national station of observation & research for desert-grassland ecosystem in xinjiang Cele 848300 China xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Health ScienceCenter Beijing 100191 China

The parasitic plant Cistanche deserticola attaches to Haloxylon ammodendron, a perennial shrub with high tolerance to salinity and drought. However, little was known about the parasite-host relation between the two species. Effects of the parasite on chlorophyll a fluorescence and nutrient accumulation in the host plant （H. am- modendron） were investigated in the Taklimakan desert. Some photosynthetic parameters of both host and non-host H. ammodendron plants were measured by in vivo chlorophyll a fluorescence technology in the field. The assimilating branches of host and non-host plants were collected and nutrient and inorganic ion contents were analyzed. The results from field experiments showed that the infection of C. deserticola reduced the non-photochemical quenching of the variable chlorophyll fluorescence （NPQ） and the potential maximum quantum yield for primary photochemistry （Fv/Fm） of the host. Compared with non-host plants, the host H. ammodendron had low nutrient, low inorganic ion contents （Na~ and K~） and low K~/Na~ ratios in the assimilating branches. It suggested that C. deserticola infection reduced the nutrient acquisition and caused damage to the photoprotection through thermal dissipation of the energy of the photosystem II in the host, resulting in a decrease in the tolerance to salinity and high radiation. It was concluded that the attachment of the parasite plant （C. deserticola） had negative effects on the growth of its host.

关键词： parasite-host relation nutrient acquisition inorganic ion content non-photochemical quenching the Taklimakan desert

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Re-evaluating the vertical mass-flux profiles of aeolian sediment at the southern fringe of the Taklimakan desert, China

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Journal of Arid Land 2015年第6期7卷 765-777页

作者： XUE Jie LEI Jiaqiang LI Shengyu GUI Dongwei MAO Donglei ZHOU Jie State Key Laboratory of desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences cele national station of observation and research for desert-grassland ecosystem Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences University of Chinese Academy of Sciences

Reliable estimation of the mass-flux profiles of aeolian sediment is essential for predicting sediment transport rates accurately and designing measures to cope with wind-erosion. Vertical mass-flux profiles from seventeen wind-erosion events were re-evaluated using five typical models based on observed data obtained from a smooth bare field at the southern fringe of the Taklimakan desert, China. The results showed that the exponential-function model and the logarithmic-function model exhibited the poorest fit between observed and predicted mass-flux profiles. The power-function model and the modified power-function model improved the fit to field data to an equivalent extent, while the five-parameter combined-function model with a scale constant（σ） of 0.00001 m（different from the σ value proposed by Fryear, which represented the height above which 50% of the total mass flux occurred） was verified as the best for describing the vertical aeolian sediment mass-flux profiles using goodness of fit（R2） and the Akaike Information Criterion（AIC） values to evaluate model performance. According to relationships among model parameters, the modified power model played a prominent explanatory role in describing the vertical profiles of the observed data, whereas the exponential model played a coordinating role. In addition, it was found that the vertical profiles could not be extrapolated using the five selected models or easily estimated using an efficient model without field observations by a near-surface sampler at 0 to 0.05 m.

关键词： vertical profile mass flux aeolian sediment wind erosion Taklimakan desert

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Magnetic mineral diagenesis in sediments of saline lake Lop Nur

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Journal of Mountain Science 2019年第3期16卷 548-560页

作者： LI Wen MU Gui-jin LIN Yong-chong SONG Hao-ze State Key Laboratory of desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences cele national station of observation and research for desert-grassland ecosystems University of Chinese Academy of Sciences School of history and Geography Minnan Normal University

Saline lakes are useful repositories for paleo-climatic records. In recent years, magnetic properties of saline lake sediments have been widely applied to establish paleo-climatic change. However,the influence factors of magnetic properties in saline lakes have not been fully understood, which complicates the paleoenvironmental ***, we present a rock magnetic analyses result of LOP_1 profile(40°26′09″′N, 90°21′23″E) from Lop Nur, a well-known saline lake, located in the eastern Tarim Basin in northwestern China. We combined the particle size, total organic content, and mineral characteristics analysis to assess the influence factors of magnetic properties in Lop Nur and its environmental significance. The results indicate that early diagenesis is the major influence factor on magnetic properties of Lop Nur saline *** greigite and pyrite are identified within organic-rich sediments, which produce zones with high and low magnetic susceptibilities, *** different authigenic iron sulfide contents in different layers are related to sedimentary environment changes. Sufficient supplies of organic matter and sulphate and low sedimentation rates favour the pyritization process. Moreover, if pyritization was constrained, intermediate greigite formed and was preserved. In oxidizing environments, sediment magnetic properties are consistent with those of source materials from Tarim Basin and are mainly controlled by particle size and hydrodynamic sorting of mainly detrital magnetite is largely unaffected by early diagenesis. Our study demonstrates that magnetic properties can provide a robust approach for studying depositional environment change in saline lake. In addition, the information obtained in this study would also provide insights into the geochemical processes of iron element in saline lakes.

关键词： Early diagenesis Magnetic properties Saline lake Lop Nur

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Vegetation fractional coverage change in a typical oasis region in Tarim River Watershed based on remote sensing

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Journal of Arid Land 2013年第1期5卷 89-101页

作者： Fei ZHANG Tashpolat TIYIP JianLi DING Mamat SAWUT Verner Carl JOHNSON NigaraTASHPOLAT DongWei GUI College of Resources and Environment Science Xinjiang University Urumqi 830046 China Key Laboratory of Oasis Ecology Xinjiang University Urumqi 830046 China Department of Physical and Environmental Sciences Colorado Mesa University Grand Junction Colorado 81501 USA xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China cele national station of observation & research for desert-grassland ecosystem in xinjiang Cele 848300 China

Vegetation fractional coverage （VFC） is an important index to describe and evaluate the ecological system. The vegetation index is widely used to monitor vegetation coverage in the field of remote sensing （RS）. In this paper, the author conducted a case study of the delta oasis of Weigan and Kuqa rivers, which is a typical saline area in the Tarim River Watershed. The current study was based on the TM/ETM＋ images of 1989, 2001, and 2006, and supported by Geographic Information System （GIS） spatial analysis, vegetation index, and dimidiate pixel model. In addition, VBSl （vegetation, bare soil and shadow indices） suitable for TM/ETM＋ irrlages, constructed with FCD （forest canopy density） model principle and put forward by ITTO （International Tropical Timber Organization）, was used, and it was applied to estimate the VFC. The estimation accuracy was later prow^n to be up to 83.52%. Further, the study analyzed and appraised the changes in vegetation patterns and revealed a pattern of spatial change in the vegetation coverage of the study area by producing the map of VFC levels in the delta oasis. Forest, grassland, and farmland were the three main land-use types with high and extremely-high coverage, and they played an important role in maintaining the vegetation. The forest area determined the changes of the coverage area, whereas the other two land types affected the directions of change. Therefore, planting trees, protecting grasslands, reclaiming farmlands, and controlling unused lands should be included in a long-term program because of their importance in keeping regional vegetation coverage. Finally, the dynamic variation of VFC in the study area was evaluated according to the quantity and spatial distribution rendered by plant cover diigital images to deeply analyze the reason behind the variation.

关键词： vegetation fractional coverage (VFC) VBSI (vegetation, bare soil and shadow indices) dimidiate pixel model delta oasis of Weigan and Kuqa rivers

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