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Wind Tunnel Study of Multiple Factors Affecting Wind Erosion from Cropland in Agro-pastoral Area of Inner Mongolia,China

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Journal of Mountain Science 2013年第1期10卷 68-74页

作者： HE Ji-jun cai qiang-guo CAO Wen-qing State Key Laboratory Incubation Base of Urban Environmental Processes and Digital Simulation Elementary Educational CollegeCapital Normal University State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Water and Soil ConservationChinese Academy of Sciences and Ministry of Water Resources Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of Sciences

In this paper,the process of wind erosion on two kinds of soil from the agro-pastoral area of Inner Mongolia are studied using wind tunnel experiments,considering the wind speed,blown angle of wind and soil moisture *** results showed that the modulus of soil wind erosion increases with an increase of wind *** the wind speed exceeds a critical value,the soil wind erosion suddenly *** critical speed for both kinds of soil is within the range of 7-8m·*** a constant wind speed,the rate of soil wind erosion changes from increasing to falling at a critical soil *** critical slope of loam soil and sandy loam soil is 20° and 10°,*** moisture content has a significant effect on wind *** wind erosion of both soils decreases with an increase of the soil water content in two treatments,however,for treatment two,the increasing trends of wind erosion for two soils with the falling of soil water content are no significant,especially for the loam soil,and in the same soil water content,the wind erosion of two soils in treatment one is significantly higher than treatment two,this indicates reducing the disturbance of soil surface can evidently control the soil wind erosion.

关键词： Agro-pastoral area Soil wind erosion Critical slope Wind tunnel experiment

Process and Mechanism for the Development of Physical Crusts in Three Typical Chinese Soils

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Pedosphere 2013年第3期23卷 321-332页

作者： BU Chong-Feng W.J.GALE cai qiang-guo WU Shu-Fang Institute of Soil and Water Conservation Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources College of Resources and Environment Northwest A&F University Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences College of Water Resources and Architectural Engineering Northwest A&F University

To compare the development of physical crusts in three typical cultivated soils of China, a black soil （Luvic Phaeozem）, a loess soil （Haplic Luvisol）, and a purple soil （Calcaric Regosol） were packed in splash plates with covered and uncovered treatments, and exposed to simulated rainfall. Meshes covered above the surfaces of half of soil samples to simulate the effects of crop residue on crusting. The results indicated a progressive breakdown of aggregates on the soil surface as rainfall continued. The bulk density and shear strength on the surface of the three soil types increased logarithmically as rainfall duration increased. During the first 30 min of simulated rainfall, the purple soil developed a 7-8 mm thick crust and the loess soil developed a 3-4 mm thick crust. The black soil developed a distinguishable, but still unstable, crust after 80 rain of simulated rainfall. Soil organic matter （SOM） content, the mean weight diameter （MWD） of soil aggregates, and soil clay content were negatively correlated with the rate of crust formation, whereas the percentage of aggregate dispersion （PAD）, the exchangeable sodium percentage （ESP）, and the silt and sand contents were positively correlated with crusting. Mechanical breakdown caused by raindrop impact was the primary mechanism of crust formation in the black soil with more stable aggregates （MWD 25.0 mm, PAD 3.1%） and higher SOM content （42.6 g kg-1）. Slaking and mechanical eluviation were the primary mechanisms of crust formation in the purple soil with low clay content （103 g kg-1）, cation exchange capacity （CEC, 228 mmol kg-1）, ESP （0.60%）, and SOM （17.2 g kg-1）. Mechanical breakdown and slaking were the most important in the loess soil with low CEC （80.6 mmol kg-1）, ESP （1.29%）, SOM （9.82 g kg-1）, and high PAD （71.7%） and MWD （4.6 mm）. Simulated residue cover reduced crust formation in black and loess soils, but increased crust formation in purple soil.

关键词： aggregate bulk density shear strength simulated rainfall soil properties

Development of Soil Crusts Under Simulated Rainfall and Crust Formation on a Loess Soil as Influenced by Polyacrylamide

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Pedosphere 2012年第3期22卷 415-424页

作者： HU Xia LIU Lian-You LI Shun-Jiang cai qiang-guo LU Yan-Li guo Jin-Rui State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875(China) Academy of Disaster Reduction and Emergency Management Beijing Normal UniversityBeijing 100875(China) Institute of Plant Nutrition and Resources Beijing Academy of Agriculture and Forestry SciencesBeijing 100097(China) Institute of Geographical Science and Natural Resources Research Chinese Academy of SciencesBeijing 100101(China)

This study evaluated the morphological characteristics and dynamic variation in characteristics of soil crust and iden-tified the relationships between soil crust and splash erosion under simulated *** effect of polyacrylamide (PAM) on soil aggregate stabilization and crust formation was also investigated.A laboratory rainfall simulation experiment was carried out using soil sample *** slices were examined under a polarized light microscopy and a scanning electron microscope (SEM).The results revealed that the soil crusts were thin and were characterized by a greater density,higher shear strength,finer porosity,and lower saturated hydraulic conductivity than the underlying *** types of crusts,i.e.,structural and depositional crusts,were *** texture was determined to be the most important soil variable influ-encing surface crust formation;depositional crust formation was primarily related to the skeleton characteristics of the soil and happened when the soil contained a high level of medium and large *** crust formation processes observed were as follows:1) The fine particles on the soil surface became spattered,leached,and then rough in response to raindrop impact and 2) the fine particles were washed into the subsoil pores while a compact dense layer concurrently formed at soil surface due to the continual compaction by the ***,the factors that influenced structural crust formation were a large amount of fine particles in the soil surface,continual impact of raindrops,dispersion of aggregates into fine particles,and the formation of a compact dense layer concurrently at the soil *** was concluded that the most important factor in the formation of soil crusts was raindrop *** polyacrylamide (PAM) was applied,it restored the soil structure and greatly increased soil aggregate *** effectively prevented crust ***,this function of PAM was not continuously effective and

关键词： depositional crust raindrop impact soil aggregates splash erosion structural crust

The characteristics of rill development and their effects on runoff and sediment yield under different slope gradients

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Journal of Mountain Science 2016年第3期13卷 397-404页

作者： HE Ji-jun SUN Li-ying GONG Hui-li cai qiang-guo JIA Li-juan Base of the State Laboratory of Urban Environmental Processes and Digital Modeling Capital Normal University Beijing 100048 China Laboratory for Controllable Synthesis and Application of Micro-sized Functional Materials Capital Normal University Beijing 100048 China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Civil Engineering University of New Mexico Albuquerque NM 87131 USA

Rill formation is the predominant erosion process in slope land in the Loess Plateau, China. This study was conducted to investigate rill erosion characteristics and their effects on runoff and sediment yielding processes under different slope gradients at a rate of 10°, 15°, 20° and 25° with rainfall intensity of 1.5 mm min-1 in a laboratory setting. Results revealed that mean rill depth and rill density has a positive interrelation to the slope gradient. To the contrary, width-depth ratio and distance of the longest rill to the top of the slope negatively related to slope gradient. All these suggested that increasing slope steepness could enhance rill headward erosion, vertical erosion and the fragmentation of the slope surface. Furthermore,total erosion tended to approach a stable maximum value with increasing slope, which implied that there is probably a threshold slope gradient where soil erosion begins to weaken. At the same time, the correlation analysis showed that there was a close connection between slope gradient and the variousindices of soil erosion: the correlation coefficients of slope gradient with maximal rill depth, number of rills and the distance of the longest rill from the top of the slope were 0.98, 0.97 and-0.98, respectively,indicating that slope gradient is the major factor of affecting the development of rills. Furthermore,runoff was not sensitive to slope gradient and rill formation in this study. Sediment concentration,however, is positively related to slope gradient and rill formation, the sediment concentrations increased rapidly after rill initiation, especially. These results may be essential for soil loss prediction.

关键词： Rill erosion Erosion processes Simulated rainfall Runoff Slope gradient

Soil erosion and management on the Loess Plateau

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Journal of Geographical Sciences 2001年第1期11卷 53-70页

作者： cai qiang-guo (Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) Institute of Geographic Sciences and Natural Resources Research CAS Beijing China

The Loess Plateau is well known to the world for its intense soil erosion. The root cause for river sedimentation of Yellow River (Huanghe) and its resultant “hanging river” in certain section is soil and water loss on the Loess Plateau. The Loess Plateau has a long cultivation history, hence population growth, vegetation degeneration and plugging constitute the chief reason for serious soil and water loss on Loess Plateau. This paper analyses several successful cases and failures in soil conservation, presents practical soil conservation technique and related benefit analysis, and discusses some effective methods adopted in China in soil erosion control, research directions and future perspectives on Loess Plateau.

关键词： soil erosion control technique management Loess Plateau

Modeling of Hillslope Runoff and Soil Erosion at Rainfall Events Using Cellular Automata Approach

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Pedosphere 2009年第6期19卷 711-718页

作者： MA Ting ZHOU Cheng-Hu cai qiang-guo State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 (China) Graduate University of the Chinese Academy of Sciences Beijing 100049 (China)

A novel quantitative cellular automata (CA) model that simulates and predicts hillslope runoff and soil erosion caused by rainfall events was developed by integrating the local interaction rules and the hillslope surface hydraulic processes. In this CA model, the hillslope surface was subdivided into a series of discrete spatial cells with the same geometric features. At each time step, water and sediment were transported between two adjacent spatial cells. The flow direction was determined by a combination of water surface slope and stochastic assignment. The amounts of interchanged water and sediment were computed using the Chezy-Manning formula and the empirical sediment transport equation. The water and sediment discharged from the open boundary cells were considered as the runoff and the sediment yields over the entire hillslope surface. Two hillslope soil erosion experiments under simulated rainfall events were carried out. Cumulative runoff and sediment yields were measured, respectively. Then, the CA model was applied to simulate the water and soil erosion for these two experiments. Analysis of simulation results indicated that the size of the spatial cell, hydraulic parameters, and the setting of time step and iteration times had a large impact on the model accuracy. The comparison of the simulated and measured data suggested that the CA model was an applicable alternate for simulating the hillslope water flow and soil erosion.

关键词： hillslope surface hydraulic parameters sediment simulation water

Potential transformation of organic matter by microbes in cryoconite,Tibetan Plateau

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Science China Earth Sciences 2024年第6期67卷 1978-1989页

作者： Bixi guo Yongqin LIU Kevin Xu ZHONG Quan SHI Chen HE qiang ZHENG Ruanhong cai State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Center for the Pan-Third Pole Environment Lanzhou UniversityLanzhou 730000China Department of Earth Oceanand Atmospheric SciencesUniversity of British ColumbiaVancouverBC V6T 1Z4Canada State Key Laboratory of Heavy Oil Processing Petroleum Molecules Engineering Center(PMEC)China University of PetroleumBeijing 102249China State Key Laboratory for Marine Environmental Science Collage of Ocean and Earth SciencesXiamen UniversityXiamen 361102China Fujian Key Laboratory of Marine Carbon Sequestration Xiamen UniversityXiamen 361005China

Microorganisms play an essential role in the glacier carbon cycle;how they transform organic matter in mountain glacial cryoconite remains to be ***,we applied ultra-high resolution Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)and deep sequencing of 16S rRNA gene,to investigate the temporal microbial transformation of dissolved organic matter(DOM)of the Tibetan Plateau *** the 60-day incubation,we found that DOM in cryoconite underwent a three-stage transformation,with decreasing bioavailability over *** microbial community did not change much in the first week while degrading DOM molecules that were associated with higher H/C_(wa)and lower O/C_(wa).During days 15-30,DOM composition remained stable while microbial diversity *** day 60,the DOM was microbially converted into a higher state of recalcitrance,with higher values of aromatic index,O/C_(wa),and lower H/C_(wa),which contained molecules containing more *** among various microbial taxa,like Cyanobacteria,Bacteroidota,Gammaproteobacteria,Firmicutes,and Actinobacteriota,drove the DOM transformation in *** study sheds light on the in-situ transformation of DOM composition meditated by microbial populations in cryoconite at a temporal scale,providing new insights into understanding the microbial roles in the glacier organic carbon transformation.

关键词： Cryoconite Dissolved organic matter Biodegradation Microbial community Temporal variation

Tetrahedral framework nucleic acids/hyaluronic acidmethacrylic anhydride hybrid hydrogel with antimicrobial and anti-inflammatory properties for infected wound healing

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International Journal of Oral Science 2024年第3期16卷 436-447页

作者： cai Qi qiang Sun Dexuan Xiao Mei Zhang Shaojingya Gao Bin guo Yunfeng Lin State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&West China Hospital of Stomatology Sichuan UniversityChengduChina Sichuan Provincial Engineering Research Center of Oral Biomaterials ChengduChina Department of Stomatology The First Medical CentreChinese PLA General HospitalBeijingChina

Bacterial resistance and excessive inflammation are common issues that hinder wound *** peptides(AMPs)offer a promising and versatile antibacterial option compared to traditional antibiotics,with additional anti-inflammatory ***,the applications of AMPs are limited by their antimicrobial effects and stability against bacterial *** are regarded as a promising drug delivery platform that could enhance the antibacterial properties and stability of ***,in this study,a composite hydrogel(HAMA/t-GL13K)was prepared via the photocross-linking method,in which tFNAs carry *** hydrogel was injectable,biocompatible,and could be instantly *** exhibited broad-spectrum antibacterial and anti-inflammatory properties by inhibiting the expression of inflammatory factors and scavenging ***,the hydrogel inhibited bacterial infection,shortened the wound healing time of skin defects in infected skin full-thickness defect wound models and reduced *** constructed HAMA/tFNA-AMPs hydrogels exhibit the potential for clinical use in treating microbial infections and promoting wound healing.

关键词： properties. hydrogel anhydride

TSC prediction and dynamic control of BOF steelmaking with state-of-the-art machine learning and deep learning methods

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Journal of Iron and Steel Research International 2024年第1期31卷 174-194页

作者： Tian-yi Xie cai-dong Zhang Quan-lin Zhou Zhi-qiang Tian Shuai Liu Han-jie guo Material Technology Research Institute Hesteel GroupShijiazhuang050023HebeiChina Tangsteel Company Hesteel GroupTangshan063611HebeiChina School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

Mathematical(data-driven)models based on state-of-the-art(SOTA)machine learning and deep learning models and data collected from 12,786 heats were established to predict the values of temperature,sample,and carbon(TSC)test,including temperature of molten steel(TSC-Temp),carbon content(TSC-C)and phosphorus content(TSC-P),which made prepa-ration for eliminating the TSC *** maximize the prediction accuracy of the proposed approach,various models with different inputs were implemented and compared,and the best models were applied to the production process of a Hesteel Group steelmaking plant in China in the *** number of tabular features(hot metal information,scrap,additives,blowing practices,and preset values)was expanded,and time series(off-gas profiles and blowing practice curves)that could reflect the entire steelmaking process were introduced as ***,the latest machine learning models(LightGBM,CatBoost,TabNet,and NODE)were used to make predictions with tabular features,and the best coefficient of determination R^(2)values obtained for TSC-P,TSC-C and TSC-Temp predictions were 0.435(LightGBM),0.857(Cat-Boost)and 0.678(LightGBM),respectively,which were higher than those of classic models(backpropagation and support vector machine).Then,making predictions was performed by using SOTA time series regression models(SCINet,DLinear,Informer,and MLSTM-FCN)with original time series,SOTA image regression models(NesT,caiT,ResNeXt,and GoogLeNet)with resized time series,and the proposed Concatenate-Model and Parallel-Model with both tabular features and time *** optimization and comparisons,it was finally determined that the Concatenate-Model with MLSTM-FCN,SCINet and Informer as feature extractors performed the best,and its R^(2)values for predicting TSC-P,TSC-C and TSC-Temp reached 0.470,0.858 and 0.710,*** field test accuracies for TSC-P,TSC-C and TSC-Temp were 0.459,0.850 and 0.685,respectively.A related importance analysis was carri

关键词： BOF steelmaking In-blow prediction TSC test Machine learning Deep learning Field application