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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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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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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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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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Influence of surface properties and antecedent environmental conditions on particulate-associated metals in surface runoff

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Environmental Science and Ecotechnology 2020年第2期2卷 9-15页

作者： Zhenyu Wang Pei Hua Heng Dai Rui Li Beidou Xi dongwei gui Jin Zhang Peter Krebs Institute of Urban Water Management Technische Universit€at Dresden01062DresdenGermany The Environmental Research Institute MOE Key Laboratory of Environmental Theoretical ChemistrySouth China Normal University510006GuangzhouChina Institute of Groundwater and Earth Sciences Jinan University510632GuangzhouChina State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution Chinese Research Academy of Environmental SciencesBeijing100012China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi830011XinjiangChina

Particulate-associated trace metals have been regarded as an important pollution source for urban surface ***,Pb,Cu,Zn and total solids(TS)washed off two different surfaces(low-elevated facade and road surfaces)under two kinds of antecedent environmental conditions(dry and snow-melting)were determined in this ***-vacuuming sweeping(WVS)and surface washing(SW)methods,representing the maximum pollution potential and common rainfall-induced wash-off condition respectively,were used to collect the particulate *** result shows that the wash-off concentrations of trace metals were found in the order of Cd(2.28±2.08 mg/l)38% and >79% of metals and TS concentrations in the facade surface and road surface runoff *** wash-off concentrations of Cd,Cu,and Zn on the road surface 45e780% higher than those on the facade *** sensitivity analysis based on the Bayesian network indicates that the wash-off concentrations of metals were mainly dependent on the antecedent environmental conditions or the surface properties while the sampling methods had a minor ***,to accurately model the pollutant migration in the surface runoff requires an improving method considering different surfaces and antecedent environment conditions.

关键词： Trace metal Road and facade Wash-off Snowmelt Bayesian network

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Simulation and prediction of monthly accumulated runoff,based on several neural network models under poor data availability

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Research in Cold and Arid Regions 2018年第6期10卷 468-481页

作者： JianPing Qian JianPing Zhao Yi Liu XinLong Feng dongwei gui College of Mathematics and System Sciences Xinjiang University 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 Geography Chinese Academy of Sciences

Most previous research on areas with abundant rainfall shows that simulations using rainfall-runoff modes have a very high prediction accuracy and applicability when using a back-propagation(BP), feed-forward, multilayer perceptron artificial neural network(ANN). However, in runoff areas with relatively low rainfall or a dry climate, more studies are needed. In these areas—of which oasis-plain areas are a particularly good example—the existence and development of runoff depends largely on that which is generated from alpine regions. Quantitative analysis of the uncertainty of runoff simulation under climate change is the key to improving the utilization and management of water resources in arid areas. Therefore, in this context, three kinds of BP feed-forward, three-layer ANNs with similar structure were chosen as models in this *** the oasis–plain region traverse by the Qira River Basin in Xinjiang, China, as the research area, the monthly accumulated runoff of the Qira River in the next month was simulated and predicted. The results showed that the training precision of a compact wavelet neural network is low; but from the forecasting results, it could be concluded that the training algorithm can better reflect the whole law of samples. The traditional artificial neural network(TANN) model and radial basis-function neural network(RBFNN) model showed higher accuracy in the training and prediction stage. However, the TANN model, more sensitive to the selection of input variables, requires a large number of numerical simulations to determine the appropriate input variables and the number of hidden-layer neurons. Hence, The RBFNN model is more suitable for the study of such problems. And it can be extended to other similar research arid-oasis areas on the southern edge of the Kunlun Mountains and provides a reference for sustainable water-resource management of arid-oasis areas.

关键词： oasis artificial neural network radial basis function wavelet function runoff simulation

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Effect of biochar amendment on soil's retention capacity for estrogenic hormones from poultry manure treatment

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Frontiers of Agricultural Science and Engineering 2017年第2期4卷 208-219页

作者： Sukhjot MANN Zhiming QI Shiv O.PRASHER Lanhai LI dongwei gui Qianjing JIANG Department of Bioresource Engineering McGill University Xinjiang Institute of Geography and Ecology Chinese Academy of Sciences

Most animals, including humans, produce natural sex hormones such as estrogens: 17β-estradiol(E2) and estrone(E1). These compounds are able to disrupt the reproductive systems of living organisms at trace concentrations(ng·L^(–1)). This experiment tests the hypothesis that 1% slow pyrolysis biochar-amended sandy soil could retain significant amount of estrogens(E1, E2)from poultry manure in its second year of application. The experiment was conducted over 46 days and consisted of a series of lysimeters containing sandy soil with biocharamended topsoil. The application rate of poultry manure was kept at 2.47 kg·m^(–2). The biochar held a significant concentration of hormone during the first year of its application. However, in the following year(current study), there was no significant retention of hormones in the biochar-amended soil. During the first year after application, the biochar was fresh, so its pores were available for hydrophobic interactions and held significant concentration of hormones. As time passed there were several biotic and abiotic changes on the surface of the biochar so that after some physical fragmentation, pores on the surface were no longer available for hydrophobic interactions. The biochar started releasing dissolved organic carbon, which facilitated greater mobility of hormones from poultry manure down the soil profile.

关键词： adsorption degradation dissolved organic carbon 17β-estradiol(E2) estrone(E1)

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Long-term simulation of growth stage-based irrigation scheduling in maize under various water constraints in Colorado, USA

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Frontiers of Agricultural Science and Engineering 2017年第2期4卷 172-184页

作者： Quanxiao FANG Liwang MA Lajpat Rai AHUJA Thomas James TROUT Robert Wayne MALONE Huihui ZHANG dongwei gui Qiang YU Agronomy College Qingdao Agricultural University State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University USDA-ARS Rangeland Resources and Systems Research Unit USDA-ARS Agricultural Water Management and Systems Research Unit USDA-ARS National Laboratory for Agriculture and the Environment State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences

Due to varying crop responses to water stress at different growth stages, scheduling irrigation is a challenge for farmers, especially when water availability varies on a monthly, seasonal and yearly basis. The objective of this study was to optimize irrigation between the vegetative(V) and reproductive(R) phases of maize under different available water levels in Colorado. Longterm(1992–2013) scenarios simulated with the calibrated Root Zone Water Quality Model were designed to meet40%–100% of crop evapotranspiration(ET) requirements at V and R phases, subject to seasonal water availabilities(300, 400, 500 mm, and no water limit), with and without monthly limits(total of 112 scenarios). The most suitable irrigation between V and R phases of maize was identified as 60/100, 80/100, and 100/100 of crop ET requirement for the 300, 400, 500 mm water available, respectively, based on the simulations from 1992 to 2013. When a monthly water limit was imposed, the corresponding suitable irrigation targets between V and R stages were 60/100,100/100, and 100/100 of crop ET requirement for the above three seasonal water availabilities, *** targets for producing higher crop yield with reduced risk of poor yield were discussed for projected five-year water availabilities.

关键词： RZWQM ET-based irrigation schedule maize water constrains

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火炬树在北美和中国空间分布差异对比及防范入侵措施

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生态学报 2024年第4期44卷 1692-1699页

作者：林敬梧桂东伟中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室乌鲁木齐830011 中国科学院大学北京100049

火炬树原产于北美洲东部,引进中国后主要栽培于贫瘠土壤上,用于植树造林和保持水土。然而其入侵性和扩散能力较强,管控不当将会严重破坏侵入地生态系统的多样性。采用了GIS和MaxEnt模型相结合的方法,模拟了火炬树在北美和中国地区的适... 详细信息

火炬树原产于北美洲东部,引进中国后主要栽培于贫瘠土壤上,用于植树造林和保持水土。然而其入侵性和扩散能力较强,管控不当将会严重破坏侵入地生态系统的多样性。采用了GIS和MaxEnt模型相结合的方法,模拟了火炬树在北美和中国地区的适宜分布区域,分析了主要环境影响因素,并利用ROC曲线验证模型结果的准确度。研究结果表明:火炬树在北美和中国的适宜分布区域都主要集中在30°-40°N气候相对湿润地带;影响MaxEnt模型预测结果的关键环境因子都是气候因子;预测模型的AUC值都大于9。但两个地区的部分环境因子的阈值范围存在明显差异,说明在入侵中国后火炬树的气候空间和生态位发生了较大变化,对中国本地的生态系统构成一定威胁。可为防疫监测和林业部门的工作提供参考依据,有助于其制定早期预警和监管措施,从而有效防治中国地区火炬树的入侵和保护生物多样性。

关键词：火炬树 MaxEnt模型空间适宜分布入侵植物环境因子生态危害

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