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伊犁河谷不同雨型下自然与人工植被的水土流失特征

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西南农业学报 2024年第2期37卷 404-411页

作者：李燕刚胡桂清张文太刘星宏孙桂丽新疆农业大学资源与环境学院/新疆土壤与植物生态过程自治区级重点实验室乌鲁木齐830052 新疆农业大学林学与风景园林学院乌鲁木齐830052

【目的】为科学防控西北干旱区草地水土流失以及比较不同雨型下植被的径流调控效果。【方法】2021—2022年雨季在伊宁市铁厂沟水土保持径流场,采用K均值方法将研究区13场侵蚀性降雨划分为3类,并监测5种自然植被(霸王、驼绒藜、伊犁绢蒿... 详细信息

【目的】为科学防控西北干旱区草地水土流失以及比较不同雨型下植被的径流调控效果。【方法】2021—2022年雨季在伊宁市铁厂沟水土保持径流场,采用K均值方法将研究区13场侵蚀性降雨划分为3类,并监测5种自然植被(霸王、驼绒藜、伊犁绢蒿、骆驼刺、苦豆子)和3种人工植被(榆树、紫穗槐、狗牙根)的产流产沙特征,探讨不同雨型下各植被的产流产沙规律,采用灰色关联度分析雨型和植被小区对产流产沙的影响。【结果】①伊犁河谷土壤侵蚀的主导雨型是B雨型(中雨量、短历时、中雨强),对坡面产流产沙的贡献程度达到53.5%。A雨型(低雨量、长历时、低雨强)和C雨型(高雨量、长历时、高雨强)贡献率较低;②自然植被的减流减沙效益高于人工植被,自然植被在A雨型下减流减沙效益最好(87.3%~95.2%),人工植被在C雨型下减流减沙效益最差(39.2%~52.7%);③降雨量和平均雨强显著影响径流深和土壤流失量(P苦豆子>霸王>紫穗槐>骆驼刺>狗牙根>榆树>驼绒藜。【结论】伊犁河谷进行植被恢复可有效减少水土流失,不同雨型下自然植被的减流减沙效益优于人工植被,单一植被的减流减沙效益与其覆盖度有关。研究结果可为西北干旱区国土绿化、土地荒漠化和水土流失防治提供理论基础。

关键词：降雨类型坡面径流植被恢复水土流失灰色关联度

Variation of Sediment Concentration and Its Drivers Under Different Soil Management Systems

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Pedosphere 2010年第5期20卷 578-585页

作者： zhang wen-tai YU Dong-Sheng SHI Xue-Zheng TAN Man-Zhi LIU Liu-Song State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) College of Geography Sciences Nanjing Normal University Nanjing 210046 (China) Graduate University of the Chinese Academy of Sciences Beijing 100049 (China)

In order to prevent soil erosion in southern China,a study was performed to determine the drivers of sediment concentration variation using simulated rainfall and four soil management systems under field *** soil management systems,i.e.,forest and grass coverage(FG),forest coverage with disturbed soil surface(FD),contour tillage(CT) and downslope tillage(DT),were exposed to two rainfall intensities(40 and 54 mm h-1) using a portable rainfall *** drivers of sediment concentration variation were determined by the variations of runoff rate and sediment concentration as well as their *** effects of the four soil management systems in preventing water and soil losses were compared using runoff rates and sediment concentrations at steady *** runoff initial stage,sediment concentration variation was mainly driven by rainfall and *** degree of sediment concentration variation driven by flow varied with different soil management *** best relationships between runoff rate and sediment concentration were identified,i.e.,reciprocal(CT),quadratic(FG and FD) and exponential(DT).At steady state,runoff rates of the four soil management systems varied slightly,whereas their sediment concentrations varied *** and CT were recommended as the best soil management systems for preventing water and soil losses.

关键词： runoff rate runoff steady state simulated rainfall soil erosion

Variability of Soil Salinity at Multiple Spatio-Temporal Scales and the Related Driving Factors in the Oasis Areas of Xinjiang,China

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Pedosphere 2014年第6期24卷 753-762页

作者： zhang wen-tai WU Hong-Qi GU Hai-Bin FENG Guang-Long WANG Ze SHENG Jian-Dong College of Grassland and Environmental Sciences Xinjiang Agricultural University State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences

Located in the inland arid area of central Asia, salt-affected farmlands take up one third of the total irrigated land area in Xinjiang of Northwest China. Spatio-temporal variability of soil salinity and the underlying mechanism are fundamental problems challenging the sustainability of oasis agriculture in China. In this study, the data of total dissolved solids(TDS) measured for soil samples collected from 27 representative study areas in the oasis areas of Xinjiang were analyzed and the coefficient of variation(CV) and stratification ratio(SR) of TDS were used to describe the lateral and vertical soil salinity variations, respectively. Weekly, monthly,and annual changes in soil salinity were also summarized. Results showed that the top(0–20 cm) soil salinity was highly variable(CV> 75%) for most studied areas. Lateral variation of soil salinity was significantly correlated with the sampling interval; as a result, a maximum sampling interval of 0.9 m was found for reducing evaluation uncertainty. The top 0–20 cm soil salt accounted for about25.2% of the total salt in the 0–100 cm soil profile. The stratification ratio values(the ratio of TDS at the 20–40 cm depth to that at the 0–20 cm depth) were mostly smaller than 1 and on average 0.92, illustrating that the top 0–20 cm soil contained slightly more salt and a considerable amount of salt still existed in subsurface and deep horizons. Irrigation reduced top soil salinity by 0.52 g kg-1, or14.6%, within the first week. On average, the relative range of soil salinity, calculated to indicate monthly changes in soil salinity, was58.2% from May to September. A 27-year experiment indicated that cultivation increased soil salinity by 44.4% at a rate of 0.14 g kg-1year-1. At small spatio-temporal scales, soil salinity variation was mainly affected by anthropogenic factors, such as irrigation and land use. However, natural factors, including groundwater, topography, and climate conditions, mainly influenced soil salinity

关键词： coefficient of variation cultivation irrigation salinization stratification ratio sustainable agriculture total dissolved solids

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新疆红花的产量等级划分及增产措施

湖北农业科学 2024年第7期63卷 110-114页

作者：孟景怡张文太胡桂清王丽耿青云王秀珍新疆农业大学资源与环境学院/新疆土壤与植物生态过程自治区级重点实验室乌鲁木齐830052 裕民县农业技术推广站新疆塔城834800 塔城地区农业技术推广中心新疆塔城834700

采用文献整合分析的方式,利用联合国粮食及农业组织官网下载的世界及中国的红花子粒产量数据,调查了新疆红花生长指标、产量及增产措施效果。结果表明,新疆红花株高、茎粗、分枝高、果球直径的均值分别为88.97、1.58、36.45、2.50 cm,... 详细信息

采用文献整合分析的方式,利用联合国粮食及农业组织官网下载的世界及中国的红花子粒产量数据,调查了新疆红花生长指标、产量及增产措施效果。结果表明,新疆红花株高、茎粗、分枝高、果球直径的均值分别为88.97、1.58、36.45、2.50 cm,单株平均果球数为15.71个,平均千粒重为43.61 g,花丝产量为152.00~1 350.00 kg/hm^(2),平均为421.06 kg/hm^(2),子粒产量为540.00~2 913.00 kg/hm^(2),平均为1 699.35 kg/hm^(2)。相关分析表明,红花花丝产量与各生长指标间存在不同程度的相关性,子粒产量未呈显著相关性。2016—2021年全球与中国红花子粒产量均值分别为949.4 kg/hm^(2)和1 458.5 kg/hm^(2),将子粒产量1 800 kg/hm^(2)及以上作为高产田,1 350~1 800 kg/hm^(2)作为中高产田,900~1 350 kg/hm^(2)作为中产田,900 kg/hm^(2)以下作为低产田。合理密植、灌溉、施肥等措施均能提高红花产量。适当提高种植密度可提高产量31%~54%,合理灌溉可增加产量33%~92%,而合理施肥可提高产量约1倍。新疆红花产量变异较大,有必要进一步探索红花高产稳产栽培技术体系。

关键词：红花(Carthamus tinctorius L.) 生长指标子粒产量增产措施新疆

Reliability ensemble averaging reduces surface wind speed projection uncertainties in the 21st century over China

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Advances in Climate Change Research 2024年第2期15卷 222-229页

作者： Zheng-tai zhang Chang-Ai XU Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China

Accurate prediction of future surface wind speed(SWS)changes is the basis of scientific planning for wind *** studies have projected SWS changes in the 21st century over China on the basis of the multi-model ensemble(MME)of the 6th Coupled Model Intercomparison Project(CMIP6).However,the simulation capability for SWS varies greatly in CMIP6 multi-models,so the MME results still have large *** this study,we used the reliability ensemble averaging(REA)method to assign each model different weights according to their performances in simulating historical SWS changes and project the SWS under different shared socioeconomic pathways(SSPs)in *** results indicate that REA considerably improves the SWS simulation capacity of CMIP6,eliminating the overestimation of SWS by the MME and increasing the simulation capacity of spatial *** spatial correlations with observations increased from 0.56 for the MME to 0.85 for ***,REA could eliminate the overestimation of the SWS by 33%in *** for southeastern China,the SWS generally decreases over China in the near term(2020-2049)and later term(2070-2099),particularly under high-emission *** SWS reduction projected by REA is twice as high as that by the MME in the near term,reaching-4%to-3%.REA predicts a larger area of increased SWS in the later term,which expands from southeastern China to eastern *** study helps to reduce the projected SWS uncertainties.

关键词： Surface wind speed Uncertainty Multi-model ensemble Reliability ensemble averaging CMIP6

Laser-rewritable room temperature phosphorescence based on in-situ polymerized tartaric acid

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Science China Chemistry 2024年第9期67卷 3029-3038页

作者： Tuo-Yu Zhou tai-wen Li Hai-Fu zhang Rui-Lin Chai Qian Zhao Penglin zhang Guang-Yue Li Qian-wen Wang Chang Li Yu Shu Zhi Fan Sheng-Hua Li College of Chemical Engineering and Materials Science College of SciencesTianjin University of Science&TechnologyTianjin 300457China College of Chemical Engineering North China University of Science and TechnologyTangshan 063210China Tianjin Key Laboratory of Multiplexed Identification for Port Hazardous Chemicals Tianjin University of Science&TechnologyTianjin 300457China

Organic room temperature phosphorescence(RTP)materials have potential applications in information technology and ***,the precise control of the afterglow in reversible manners remains challenging for organic ***,we report a kind of organic RTP material fabricated by simple heating mixtures of tartaric acid(TA)and aromatic acids,which can switch their phosphorescence by *** mixtures show tunable phosphorescence from indigo to orange with phosphorescence efficiency of up to 53.99% due to locking different organic luminogens by the TA-formed matrix through the noncovalent *** afterglow of those materials lasts a few seconds and disappears by water fumigation,which can be repeated in response to wet/heat *** drop-casting those materials on glass slides,a laser-repatternable phosphorescence is achieved by facile laser direct writing and quenched by water *** results open the opportunity for the design of smart stimuli-responsive phosphorescence materials from sustainable natural products.

关键词： room temperature phosphorescence tunable afterglows tartaric acid laser direct writing stimuli-response

State of the art of lightweight aggregates used in lightweight refractories for working lining of high-temperature furnaces

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Journal of Iron and Steel Research International 2024年第6期31卷 1320-1343页

作者： Wei zhang wen-yong Dai Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina Research and Development Department AGC Plibrico(Dalian)Industries Inc.Dalian 116600LiaoningChina

Lightweight refractories for the working lining of high-temperature furnaces play an important role in the smelting of advanced steels and *** prepare lightweight refractories for the working lining of high-temperature furnaces,the synthesis of lightweight aggregates is the ***,the research on the synthesis of lightweight aggregates with high service temperature,low thermal conductivity,high strength,and good slag resistance has received widespread *** available literature on the synthesis of lightweight aggregates was summarized,including corundum,mullite,mullite-corundum,spinel,corundum-spinel,cordierite,cordierite-mullite,calcium hexaluminate,corundum-calcium hexaluminate,bauxite,magnesia,magnesia-based,and forsterite-based ***,the future development trend of lightweight aggregates was proposed.

关键词： Lightweight aggregate Lightweight refractory Working lining Apparent porosity Closed porosity Thermal conductivity Pore-forming approach

Porous nanofibrous dressing enables mesenchymal stem cell spheroid formation and delivery to promote diabetic wound healing

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Chinese Journal of Chemical Engineering 2024年第4期68卷 156-164页

作者： Kexin zhang wenmin zhang Heng An Zhe Huang Yanzhen wen Xiangyu Jiao Yongqiang wen College of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan 030024China Beijing Key Laboratory for Bioengineering and Sensing Technology Daxing Research InstituteSchool of Chemistry&Biological EngineeringUniversity of Science&Technology BeijingBeijing 100083China

Delayed and nonhealing of diabetic wounds imposes substantial economic burdens and physical pain on *** stem cells(MSCs)promote diabetic wound *** when MSCs aggregate into multicellular spheroids,their therapeutic effect is ***,traditional culture platforms are inadequate for the efficient preparation and delivery of MSC spheroids,resulting in inefficiencies and inconveniences in MSC spheroid *** this study,a three-dimensional porous nanofibrous dressing(NFD)is prepared using a combination of electrospinning and homogeneous *** thermal crosslinking,the NFD not only achieves satisfactory elasticity but also maintains notable *** the design of its structure and chemical composition,the NFD allows MSCs to spontaneously form MSC spheroids with controllable sizes,serving as MSC spheroid delivery systems for diabetic wound *** importantly,MSC spheroids cultured on the NFD exhibit improved secretion of vascular endothelial growth factor,basic fibroblast growth factor,and hepatocyte growth factor,thereby accelerating diabetic wound *** NFD provides a competitive strategy for MSC spheroid formation and delivery to promote diabetic wound healing.

关键词： Electrospinning Homogenization Biomedical engineering Nanomaterials Stem cell spheroids Diabetic wound healing

Distributed dynamic task allocation for unmanned aerial vehicle swarm systems:A networked evolutionary game-theoretic approach

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Chinese Journal of Aeronautics 2024年第6期37卷 182-204页

作者： Zhe zhang Ju JIANG Haiyan XU wen-An zhang College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China

Task allocation is a key aspect of Unmanned Aerial Vehicle(UAV)swarm collaborative *** an continuous increase of UAVs’scale and the complexity and uncertainty of tasks,existing methods have poor performance in computing efficiency,robustness,and realtime allocation,and there is a lack of theoretical analysis on the convergence and optimality of the *** paper presents a novel intelligent framework for distributed decision-making based on the evolutionary game theory to address task allocation for a UAV swarm system in uncertain scenarios.A task allocation model is designed with the local utility of an individual and the global utility of the ***,the paper analytically derives a potential function in the networked evolutionary potential game and proves that the optimal solution of the task allocation problem is a pure strategy Nash equilibrium of a finite strategy ***,a PayOff-based Time-Variant Log-linear Learning Algorithm(POTVLLA)is proposed,which includes a novel learning strategy based on payoffs for an individual and a time-dependent Boltzmann *** former aims to reduce the system’s computational burden and enhance the individual’s effectiveness,while the latter can ensure that the POTVLLA converges to the optimal Nash equilibrium with a probability of *** simulation results show that the approach is optimal,robust,scalable,and fast adaptable to environmental changes,even in some realistic situations where some UAVs or tasks are likely to be lost and increased,further validating the effectiveness and superiority of the proposed framework and algorithm.

关键词： Task allocation Unmanned Aerial Vehicles(UAV) Game theory Log-linear learning Distributed optimization algorithm