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5篇 您的检索式:作者名="HeQiang Du"
    题名 作者 年代 出处 被引量
1Estimation of the quantity of aeolian saltation sediments blown into the Yellow River from the Ulanbuh Desert,China显示文摘The Ulanbuh Desert borders the upper reach of the Yellow River.Every year,a mass of aeolian sand is blown into the Yellow River by the prevailing wind and the coarse aeolian sand results in serious silting in the Yellow River.To estimate the quantity of aeolian sediments from the Ulanbuh Desert blown into the Yellow River,we simulated the saltation processes of aeolian sediments in the Ulanbuh Desert.Then we used a saltation submodel of the IWEMS(Integrated Wind-Erosion Modeling System)and its accompanying RS(Remote Sensing)and GIS(Geographic Information System)modules to estimate the quantity of saltation sediments blown into the Yellow River from the Ulanbuh Desert.We calibrated the saltation submodel by the synchronous observation to wind velocity and saltation sediments on several points with different vegetation cover.The vegetation cover,frontal area of vegetation,roughness length,and threshold friction velocity in various regions of the Ulanbuh Desert were obtained using NDVI(Normalized Difference Vegetation Index)data,measured sand-particle sizes,and empirical relationships among vegetation cover,sand-particle diameters,and wind velocity.Using these variables along with the observed wind velocities and saltation sediments for the observed points,the saltation model was validated.The model results were shown to be satisfactory(RMSE less than 0.05 and|Re|less than 17%).In this study,a subdaily wind-velocity program,WINDGEN,was developed using this model to simulate hourly wind velocities around the Ulanbuh Desert.By incorporating simulated hourly wind-velocity and wind-direction data,the quantity of saltation sediments blown into the Yellow River was calculated with the saltation submodel.The annual quantity of aeolian sediments blown into the Yellow River from the Ulanbuh Desert was 5.56×106t from 2001 to 2010,most of which occurred in spring(from March to May);for example,6.54×105tons of aeolian sand were blown into the Yellow River on 25 April,2010.However,in summer and winter,the saltation process occasionally occurred.This research has supplied some references to prevent blown sand hazards and silting in the Yellow River.HeQiang DU Xian XUE Tao WANG 2014Journal of Arid Land2014,6,2:11
2Oasis Functional Stability Evaluation Based on Multiple Indicators, Northwest China显示文摘We produced and analyzed oasis structure information, and evaluated oasis functional stability using the multiple indicators based on Remote Sensing(RS) and Geographical Information System(GIS) in the arid region of China in 2015. The results showed that the oases area was 193,734 km^2, accounting for 8.17% of the arid region of China. The spatial difference in the functional stability of oases was obvious. The Beijiang zone had the highest functional stability and was relatively stable state, and the Hexi Corridor-Alashan Plateau zone had the lowest functional stability and was relatively unstable. The functional stability is dominated by production and ecological functions, which have regional differences. Increasing oasis agricultural output, strengthening highway infrastructure construction and paying attention to education will become important ways to improve oasis functional stability. Water resources determine the ecological function, thus affecting the oasis functional stability. The results provide references for the formulation of related policies according to local conditions.LI Sen ZHANG Zhishan WANG Tao YAN Changzhen DU Heqiang 2020Acta Geologica Sinica(English Edition)2020,94,3:3
3Numerical simulations of flow and sediment transport within the Ning-Meng reach of the Yellow River,northern China显示文摘Effective management of a river reach requires a sound understanding of flow and sediment transport generated by varying natural and artificial runoff conditions. Flow and sediment transport within the Ning-Meng reach of the Yellow River(NMRYR), northern China are controlled by a complex set of factors/processes, mainly including four sets of factors:(1) aeolian sediments from deserts bordering the main stream;(2) inflow of water and sediment from numerous tributaries;(3) impoundment of water by reservoir/hydro-junction; and(4) complex diversion and return of irrigation water. In this study, the 1-D flow & sediment transport model developed by the Yellow River Institute of Hydraulic Research was used to simulate the flow and sediment transport within the NMRYR from 2001 to 2012. All four sets of factors that primarily control the flow and sediment transport mentioned above were considered in this model. Compared to the measured data collected from the hydrological stations along the NMRYR, the simulated flow and sediment transport values were generally acceptable, with relative mean deviation between measured and simulated values of <15%. However, simulated sediment concentration and siltation values within two sub-reaches(i.e., Qingtongxia Reservoir to Bayan Gol Hydrological Station and Bayan Gol Hydrological Station to Toudaoguai Hydrological Station) for some periods exhibited relatively large errors(the relative mean deviations between measured and simulated values of 18% and 25%, respectively). These errors are presumably related to the inability to accurately determine the quantity of aeolian sediment influx to the river reach and the inflow of water from the ten ephemeral tributaries. This study may provide some valuable insights into the numerical simulations of flow and sediment transport in large watersheds and also provide a useful model for the effective management of the NMRYR.DOU Shentang YU Xin DU Heqiang ZHANG Fangxiu 2017Journal of Arid Land2017,9,4:2
4Estimation of saltation emission in the Kubuqi Desert, North China显示文摘Du Heqiang Xue Xian Wang Tao 2014Science of the Total Environment2014,2014,47:1
5Field determination for roughness length above the different non-erodible surfaces显示文摘Non-erodible elements, for its disturbance to the near-surface airflow, have been widely used in arid and semi-arid regions to protect the surface from wind erosion. Roughness length was usually used to evaluate the protection effect of non-erodible elements from wind erosion. In this study, the wind profiles above five types of non-erodible surfaces including gravel, wheat straw checkerboard barriers, cotton stem checkerboard barriers, shrubs, and herbs were measured and analyzed. The wind velocities above these surfaces increased with height approximately in logarithmic functions. The roughness length of different non-erodible surfaces was calculated by the functions of wind profiles. The results reveal that:(1) Roughness length increased with wind velocity in given wind velocity ranges.(2) On vegetative surfaces, wind did not effectively bend the stems. The threshold wind velocity for bending the stems of Achnatherum splendens was 4 m/s, 10 m/s for Agropyron cristatum, and for Artemisia ordosica, no obvious bending of stems even for wind velocity reaching 12 m/s.(3) Correlation analysis results show that the vegetation's coverage and frontal area affect the roughness length more significantly than the other parameters.(4) The protective results of these non-erodible elements were evaluated. The checkerboard sand barriers made of cotton stem could provide more effective protection than that made of wheat straw. In the same coverage conditions, vegetation could provide more effective protection from wind erosion than gravel, and the blending of different non-erodible elements especially the combination of blending of vegeation and checkerboard sand barriers could provide more effective protection to the surface.HeQiang Du Tao Wang Xian Xue 2017Research in Cold and Arid Regions2017,9,1:0
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