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Estimation and testing of linkages between forest structure and rainfall interception characteristics of a Robinia pseudoacacia plantation on China’s Loess Plateau

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Journal of Forestry Research 2022年第2期33卷 529-542页

作者： changkun ma Yi Luo Mingan Shao Xiaoxu Jia State Key Laboratory of Eco-Hydraulics in Northwest Arid Region Xian University of TechnologyXianChina Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China

Understanding the interaction between canopy structure and the parameters of interception loss is essential in predicting the variations in partitioning rainfall and water resources as affected by changes in canopy structure and in implementing water-based management in semiarid forest *** this study,seasonal variations in rainfall interception loss and canopy storage capacity as driven by canopy structure were predicted and the linkages were tested using seasonal filed *** study was conducted in nine 50 m×50 m Robinia pseudoacacia plots in the semiarid region of China’s Loess *** rain-fall,throughfall and stemflow were measured in seasons with and without leaves in 2015 and *** show that measured average interception loss for the nine plots were 17.9% and 9.4% of gross rainfall during periods with leaves (the growing season) and without leaves, respectively. Average canopy storage capacity estimated using an indirect method was 1.3 mm in the growing season and 0.2 mm in the leafless season. Correlations of relative interception loss and canopy storage capacity to canopy variables were highest for leaf/wood area index (LAI/WAI) and canopy cover, fol-lowed by bark area, basal area, tree height and stand density. Combined canopy cover, leaf/wood area index and bark area multiple regression models of interception loss and canopy storage capacity were established for the growing season and in the leafless season in 2015. It explained 97% and 96% of the variations in relative interception loss during seasons with and without leaves, respectively. It also explained 98% and 99% of the variations in canopy storage capacity during seasons with and without leaves, respectively. The empiri-cal regression models were validated using field data col-lected in 2016. The models satisfactorily predicted relative interception loss and canopy storage capacity during seasons with and without leaves. This study provides greater under-standing a

关键词： Rainfall interception loss Canopy storage Canopy structure Regression models China’s Loess Plateau

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Impact of climate change on the streamflow in the glacierized Chu River Basin, Central Asia

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Journal of Arid Land 2015年第4期7卷 501-513页

作者： ma changkun SUN Lin LIU Shiyin SHAO Ming'an LUO Yi College of Natural Resources and Environment Northwest A&F University Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences

Catchments dominated by meltwater runoff are sensitive to climate change as changes in precipitation and temperature inevitably affect the characteristics of glaciermelt/snowmelt, hydrologic circle and water resources. This study simulated the impact of climate change on the runoff generation and streamflow of Chu River Basin （CRB）, a glacierized basin in Central Asia using the enhanced Soil and Water Assessment Tool （SWAT）. The model was calibrated and validated using the measured monthly streamflow data from three discharge gauge stations in CRB for the period 1961-1985 and was subsequently driven by downscaled future climate projections of five Global Circulation Models （GCMs） in Coupled Model Inter-comparison Project Phase 5 （CMIP5） under three radiative forcing scenarios （RCP2.6, RCP4.5 and RCP8.5）. In this study, the period 1966-1995 was used as the baseline period, while 2016-2045 and 2066-2095 as the near-future and far-future period, respectively. As projected, the climate would become warmer and drier under all scenarios in the future, and the future climate would be characterized by larger seasonal and annual variations under higher RCP. A general decreasing trend was identi- fied in the average annual runoff in glacier （-26.6% to -1.0%）, snow （-21.4% to ＋1.1%） and streamflow （-27.7% to -6.6%） for most of the future scenario periods. The projected maximum streamflow in each of the two future scenarios occurred one month earlier than that in the baseline period because of the reduced streamflow in summer months. Results of this study are expected to arouse the serious concern about water resource availability in the headwater region of CRB under the continuously warming climate. Changes in simulated hydrologic outputs underscored the significance of lowering the uncertainties in temperature and precipitation projection.

关键词： glacier snow meltwater runoff climate change hydrologic modeling

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高应力条件下尾矿破碎特性及坝体稳定性研究

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中国安全生产科学技术 2022年第2期18卷 20-26页

作者：杨春和张超马昌坤李雪婷马垒中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071 中科院武汉岩土力学研究所矿山边坡安全风险预警与灾害防控应急管理部重点实验室湖北武汉430071

高应力条件下尾矿破碎特性与坝体稳定性研究是高尾矿坝避免溃坝事故的重要参考。分析尾矿颗粒破碎过程中级配曲线的演化规律,提出采用BET测试颗粒比表面积以定量化表征颗粒破碎指标;在室内高应力三轴试验的基础上,阐述高应力条件下尾矿... 详细信息

高应力条件下尾矿破碎特性与坝体稳定性研究是高尾矿坝避免溃坝事故的重要参考。分析尾矿颗粒破碎过程中级配曲线的演化规律,提出采用BET测试颗粒比表面积以定量化表征颗粒破碎指标;在室内高应力三轴试验的基础上,阐述高应力条件下尾矿的力学行为,提出高应力条件下尾矿强度准则,并基于该准则对工程实例进行应用分析。结果表明:相比于常用破碎指标,从能量观点出发的BET法比表面积表征尾矿颗粒破碎更为合理;采用线性Mohr-Coulomb准则计算尾矿在低应力阶段的内摩擦角,采用幂函数Mohr强度准则计算尾矿在高应力阶段的内摩擦角;提出1套考虑高应力条件下尾矿强度折减的坝体稳定性分析方法,以供实际工程参考。

关键词：尾矿坝高应力破碎指标强度准则

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西北旱区农业高质量发展体系的生态农业内涵与路径

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农业工程学报 2023年第20期39卷 221-232页

作者：陶汪海邓铭江王全九苏李君马昌坤宁松瑞西安理工大学西安710048 西北旱区生态水利国家重点实验室西安710048 寒旱区水资源与生态水利工程研究中心乌鲁木齐830099

西北旱区自然条件恶劣,水土资源不匹配,农业发展受到诸多障碍。为探索一条突破环境制约,且资源集约高效利用的现代农业发展道路,该文系统分析了国内外农业发展沿革与趋势,明晰了西北旱区农业发展面临的问题与挑战,构建了针对西北旱区的... 详细信息

西北旱区自然条件恶劣,水土资源不匹配,农业发展受到诸多障碍。为探索一条突破环境制约,且资源集约高效利用的现代农业发展道路,该文系统分析了国内外农业发展沿革与趋势,明晰了西北旱区农业发展面临的问题与挑战,构建了针对西北旱区的生态农业发展理论框架,提出了西北旱区多业态生态农业结构与提质增效途径。研究发现,生态农业是通过现代科学技术与生态工程原理,形成产供销全链条绿色循环且生态功能持续提升的一种农业体系。生态农业应具备农业资源集约化、生产过程生态化、农业经营产业化、农业管理智能化、农业功能多元化五大基本特征。该文构建了以高效益、高效率、高品质、高素质为目标的生态农业高质量发展体系,提出了集优质棉业、精品果业、优质粮草、生态养殖、特色小镇、地理产品为一体的西北旱区多业态生态农业结构,阐明了以节水控盐协同模式、生境智能管控模式、“园机”一体化模式、循环经济发展模式、城乡统筹发展模式、“三产”一体化模式为核心的西北旱区生态农业提质增效技术体系,明确了以农业高效用水和生态功能提升为核心的关键途径。同时实践经验显示,绿色可持续的生态农业发展理念对促进区域经济水平与生态环境建设效果显著,如陕西眉县绿色林果业品牌入选中欧地理标志产品名单、综合产值达58.5亿元,甘肃广河县和宁夏青铜峡市畜禽粪污资源化率超90%,新疆生产建设兵团七十七团通过秸秆资源化技术单产增加8%、土壤有机质达21.2%,内蒙古科尔沁旗通过优质牧草种植、良种培育的生态畜牧业实现了规模生产与草场保护的双赢。

关键词：生态农业理论体系西北旱区高质量发展

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New Developments in Catalytic Asymmetric [2,3]-Sigmatropic Rearrangement of Sulfur Ylides Generated from Carbenoids

New Developments in Catalytic Asymmetric [2,3]-Sigmatropic R...

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中国化学会第十三届金属有机化学学术讨论会

作者： Ming ma, Lingling Peng, changkun Li and Jianbo Wang Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education. Department of Chemical Biology, College of Chemistry, Peking University, Beijing 100871

＜正＞ The catalytic asymmetric inductions in oxygen or sulfur ylides generated from carbenoids have attracted considerable attention in recent years. In particular, the [2,3]-sigmatropic rearrangement of sulfur ylides generates a chiral center containing a C-S bond, which is difficult to prepare with other methods. However, catalytic asymmetric reaction of sulfur ylide has been less developed. We have carried out the catalytic asymmetric [2,3]-sigmatropic rearrangement of sulfur ylides, which are generated from the reaction of aryl diazoacetate and

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西北现代生态灌区建设理论与技术保障体系构建

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农业机械学报 2022年第8期53卷 1-13页

作者：邓铭江陶汪海王全九苏李君马昌坤宁松瑞西安理工大学省部共建西北旱区生态水利国家重点实验室西安710048 寒旱区水资源与生态水利工程研究中心乌鲁木齐830000

灌区是我国粮食安全和现代农业发展的基础保障,同时也是区域经济发展和生态环境保护的重要基石。然而西北地区独特的气候、地貌及社会经济状况导致了灌区生产能力和生态服务功能难以满足现代生态农业发展的需求。通过系统分析西北灌溉... 详细信息

灌区是我国粮食安全和现代农业发展的基础保障,同时也是区域经济发展和生态环境保护的重要基石。然而西北地区独特的气候、地貌及社会经济状况导致了灌区生产能力和生态服务功能难以满足现代生态农业发展的需求。通过系统分析西北灌溉农业发展中面临的水资源过度开发、土壤盐碱化严重、生态环境功能低下等方面的问题,阐述了西北现代生态灌区的内涵与特征,并基于农业生产“功能水分”来源,将西北灌区划分成了灌溉依赖型灌区、灌溉主导型灌区、灌溉补充型灌区和灌溉提质型灌区4类。以灌区农业生产系统、物能输配系统、生态环境系统为建设对象,提出了灌区生态服务功能优化配置、灌区农田物能调控和灌区生态系统安全评估三大核心理论,构建了灌区系统控污与景观价值提升技术、灌排系统管控技术、作物生境要素综合调控技术三大关键技术,从而形成了西北现代生态灌区理论与技术保障体系,为我国西北灌溉农业高质量可持续发展提供理论与技术指导。

关键词：现代生态灌区生态景观生态功能灌排系统物能调控生境要素

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