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| 1 | Effects of alfalfa coverage on runoff,erosion and hydraulic characteristics of overland flow on loess slope plots显示文摘An evaluation of the interactions between vegetation,overland and soil erosion can provide valuable insight for the conservation of soil and water.An experiment was conducted to study water infiltration,runoff generation process,rate of sediment erosion,and hydrodynamic characteristics of overland flow from a sloping hillside with different draw-off discharges from alfalfa and control plots with 20°slope.The effect of alfalfa on runoff and sediment transport reduction was quantitatively analyzed.Alfalfa was discussed for its ability to reduce the overland flow scouring force or change the runoff movement.Compared to the bare-soil plots,alfalfa plots generated a 1.77 times increase in infiltration rate.Furthermore,the down-slope water infiltration rate for the bare soil plots was higher than in the up-slope,while the opposite was found in the alfalfa plots.In addition,alfalfa had a significant effect on runoff and sediment yield.In comparison to the control,the runoff coefficient and sediment transportation rate decreased by 28.3%and 78.4%in the grass slope,respectively.The runoff generated from the alfalfa and bare-soil plots had similar trends with an initial increase and subsequent leveling to a steady-state rate.The transport of sediment reduced with time as a consequence of the depletion of loose surface materials.The maximum sediment concentration was recorded within the first few minutes of each event.The alfalfa plots had subcritical flow while the baresoil plots had supercritical flow,which indicate that the capability of the alfalfa slope for resisting soil erosion and sediment movement was greater than for bare soil plots.Moreover,the flow resistance coefficient and roughness coefficient for the alfalfa plots were both higher than for the bare-soil plots,which indicate that overland flow in alfalfa plots had retarded and was blocked,and the flow energy along the runoff path had gradually dissipated.Finally,the ability to erode and transport sediment had decreased. | Shufang WU Pute WU Hao FENG G.P.Merkley | 2011 | Frontiers of Environmental Science & Engineering2011，5，1： | 11 |
| 2 | Dry/wet climate zoning and delimitation of arid areas of Northwest China based on a data-driven fashion显示文摘The division of arid areas is important in water and land resources management, planning and for a long-term agricultural, economic and social planning. Northwest China(NW) dominates the main arid areas in China. There is thus a need to adopt adequate concepts relative to the scope of arid areas of NW China and identify its climate types and characteristics. In this study, we analyzed climatic data over the last 30 years(1981–2010) from 191 stations in three provinces and three autonomous regions of NW China. The factor-cluster analysis tech- nique(FC), an objective and automated method was employed to classify the dry/wet climate zones. The traditional methods with predefined thresholds were adopted for providing a comparison with FC. The results showed that the wet/dry climate zones by FC were mainly distributed along mountains, rivers and desert borders. Climate-division boundaries relied heavily on the major terrain features surrounding the grouped stations. It also showed that the climate was dry in the plain sandy areas but relatively wet in the high mountain areas. FC method can reflect the climate characteristics more fully in NW China with varied and complicated topography, and outperform the tradi- tional climate classifications. Arid areas of NW China were defined as four climate types, including five resultant classes in FC classifications. The Qinling and Da Hinggan Mountains were two important boundaries, besides main administrative boundaries. The results also indicated that there are some differences between two traditional clas- sifications. The precipitation moved and fluctuated to an extent, which confirmed that climate change played an important role in the dry/wet climate zoning, and the boundaries of dry/wet climate zones might change and migrate with time. This paper is expected to provide a more in-depth understanding on the climate characteristics in arid areas of NW China, and then contribute to formulate reasonable water and land management planning and agri- cultural production programs. | QingLing GENG PuTe WU QingFeng ZHANG XiNing ZHAO YuBao WANG | 2014 | Journal of Arid Land2014，6，3： | 9 |
| 3 | A SIMPLIFIED BRAUER'S THEOREM ON MATRIX EIGENVALUES显示文摘Let A= (aij)∈Cn×n and ri = ∑ j≠i|aij|. Suppose thatforeach row of A there isatleastonenonzero off-diagonalentry. Itis proved thatalleigenvalues ofAarecontained in Ω~= ∪aij≠0,i≠j{z∈C:|z- aii||z- ajj|≤rirj}. The resultre- duces the num berofovals in originalBrauer’stheorem in m any cases. Eigenval- ues(and associated eigenvectors) thatlocate in theboundary ofΩ~ arediscussed. | LiLuoluo Dept.ofScientific Com puting and Com puter Applications, Mathem atics and Com putation College, Zhong- shan Univ., Guangzhou 510275. | 1999 | Applied Mathematics(A Journal of Chinese Universities)1999，14，3： | 8 |
| 4 | Feedbacks between vegetation restoration and local precipitation over the Loess Plateau in China显示文摘The implementation of large-scale vegetation restoration over the Chinese Loess Plateau has achieved clear improvements in vegetation fraction,as evidenced by large areas of slopes and plains being restored to grassland or forest.However,such large-scale vegetation restoration has altered land-atmosphere exchanges of water and energy,as the land surface characteristics have changed.These variations could affect regional climate,especially local precipitation.Quantitatively evaluating this feedback is an important scientific question in hydrometeorology.This study constructs a coupled land-atmosphere model incorporating vegetation dynamics,and analyzes the spatio-temporal changes of different land use types and land surface parameters over the Loess Plateau.By considering the impacts of vegetation restoration on the water-energy cycle and on land-atmosphere interactions,we quantified the feedback effect of vegetation restoration on local precipitation across the Loess Plateau,and discussed the important underlying processes.To achieve a quantitative evaluation,we designed two simulation experiments,comprising a real scenario with vegetation restoration and a hypothetical scenario without vegetation restoration.These enabled a comparison and analysis of the net impact of vegetation restoration on local precipitation.The results show that vegetation restoration had a positive effect on local precipitation over the Loess Plateau.Observations show that precipitation on the Loess Plateau increased significantly,at a rate of 7.84 mm yr^(-2),from 2000 to 2015.The simulations show that the contribution of large-scale vegetation restoration to the precipitation increase was about 37.4%,while external atmospheric circulation changes beyond the Loess Plateau contributed the other 62.6%.The average annual precipitation under the vegetation restoration scenario over the Loess Plateau was 12.4%higher than that under the scenario without vegetation restoration.The above research results have important theoretical and practical significance for the ecological protection and optimal development of the Loess Plateau,as well as the sustainable management of vegetation restoration. | Baoqing ZHANG Lei TIAN Xining ZHAO Pute WU | 2021 | Science China Earth Sciences2021，64，6： | 6 |
| 5 | Model of soybean NDVI change based on time series显示文摘Normalized Difference Vegetation Index(NDVI)has been found to have good correlations with many physical properties of soybean surfaces.Due to the factors of air temperature,humidity,solar radiation,soil moisture,etc.,NDVI of soybean varies dynamically in a day.The establishment of the soybean NDVI prediction model at different times in a day can effectively modify this variation.The soybean NDVI values are continuously monitored in hours during soybean seeding,flowering&podding and maturating stages by way of Green Seeker.Results show that the trend of NDVI change every day in the three stages is taken on as a reverse parabola.The NDVI value reaches to the maximum at 8 am or 9 am and decreases to its minimum at 2 pm before a moderate rise.A model for intraday and long-term NDVI change for soybean is built.The test of the model with independent data indicates that the precision meets the demands,with the root mean square error(RMSE)of each day being 3.95,5.45 and 2.86 for the seeding stage,the bean podding stage and the maturation period,respectively.The prediction RMSEs of the soybean NDVI model for soybeans of the three stages for the fifth day are 5.75,2.65 and 5.51,respectively and the prediction RMSEs for the sixth day are 9.74,2.82 and 14.04,respectively according to the data from the first four days. | Zhang Zhitao Yubin Lan Wu Pute Han Wenting | 2014 | International Journal of Agricultural and Biological Engineering2014，7，5： | 3 |
| 6 | Comparison of classification methods for the divisionsof wet/dry climate regions in Northwest China显示文摘 | Geng qingling Wu Pute Zhao Xining | 2014 | International Journal of Climatology2014，34，7： | 1 |
| 7 | Cleidocranial dysplasia-review with an emphasis on otologieal and audiological manifestations 显示文摘 | Segal N Pute~nan M | 2007 | Int J Pediatr Otorhinolaryngol2007，71，： | 1 |
| 8 | Simulation of soil water dy- namics for uncropped ridges and furrows under irrigation conditions 显示文摘 | Zhang Yongyong Wu Pute Zhao Xining | 2013 | Canadian Journal of Soil Science2013，93，1： | 1 |
| 9 | Drought variation trends in different subregions of the Chinese Loess Plateau over the past four decades显示文摘 | ZhangBaoqing Wu Pute Zhao Xining | 2012 | Agricul- tural Water Management2012，115，： | 1 |
| 10 | Physico-chemical properties and antioxidant capacity of different jujube (Ziziphus jujuba Mill ) cultivars grown in loess plateau of China显示文摘 | Gao Qinghan Wu Pute John W.Parry | | 0，，26： | 1 |
| 11 | Variable-rate con- trolled sprinklers for precision irrigation 显示文摘 | Han Wenting Fen Hao Wu Pute | 2007 | ASABE Annual In- ternational Meeting Technical Papers2007，，6： | 1 |
| 12 | Effect of foaming pressure on the properties of porous Si 3 N 4 ceramic fabricated by technique combining foaming and pressureless-sintering显示文摘 | Xiangming Li Pute Wu Delan Zhu | 2013 | Scripta Materialia2013，，： | 1 |
| 13 | The dynamic effects of pastures and crop on runoff and sediments reduction at loess slopes under simulated rainfall conditions显示文摘 | Zhao Xining Huang Jun Wu Pute | 2014 | Catena2014，119，3： | 1 |
| 14 | A survey on wireless sensor network infrastructure for agriculture 显示文摘 | Yu Xiaoqing Wu Pute Han Wenting | 2013 | Computer Standards & Interfaces2013，35，1： | 1 |
| 15 | Effect of foaming pressure on the properties of porous Sin N4 ceramic fabrica- ted by a technique combining foaming and pressureless sin- tering显示文摘 | Li Xiangming Wu Pute Zhu Delan | 2013 | Script Mater2013，68，： | 1 |
| 16 | Assessing the spatial and temporal variation of the rainwater harvesting potential (1971–2010) on the Chinese Loess Plateau using the VIC model显示文摘 | Baoqing Zhang Pute Wu Xining Zhao Xiaodong Gao Yinguang Shi | 2014 | Hydrol Process2014，，3： | 1 |
| 17 | Drought variation trends in different subregions of the Chinese Loess Plateau over the past four decades显示文摘 | Baoqing Zhang Pute Wu Xining Zhao Yubao Wang Jiawen Wang Yinguang Shi | 2012 | Agricultural Water Management2012，，： | 1 |
| 18 | Estimating the spatial means and variability of root-zone soil moisture in gullies using measurements from nearby uplands 显示文摘 | Gao Xiaodong Wu Pute Zhao Xining | 2013 | Journal of Hydrology2013，476，1： | 1 |
| 19 | Effects of rainfall intensity, underlying surface and slope gradient on soil infiltration under simulated rainfall experiments显示文摘 | Jun Huang Pute Wu Xining Zhao | 2012 | Catena2012，，： | 1 |
| 20 | Hydraulic design procedure for drip irrigation submain unit based on relative flow difference 显示文摘 | Zhang Lin Wu Pute Zhu Delan | 2013 | Irrigation Science2013，31，5： | 1 |
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