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Effects of long-term fencing on soil microbial community structure and function in the desert steppe,China

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Journal of Arid Land 2024年第3期16卷 431-446页

作者： PAN Yaqing KANG Peng QU Xuan RAN Yichao li xinrong Shapotou Desert Research and Experiment Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Biological Science and Engineering North Minzu UniversityYinchuan 750021China

One of the goals of grazing management in the desert steppe is to improve its ecosystem.However,relatively little is known about soil microbe communities in the desert steppe ecosystem under grazing management.In this study,we investigated the diversity and aboveground biomass of Caragana korshinskii Kom.shrub communities in long-term fencing and grazing areas,combined with an analysis of soil physical-chemical properties and genomics,with the aim of understanding how fence management affects plant-soil-microbial inter-relationships in the desert steppe,China.The results showed that fence management(exclosure)increased plant diversity and aboveground biomass in C.korshinskii shrub area and effectively enhanced soil organic carbon(233.94%),available nitrogen(87.77%),and available phosphorus(53.67%)contents.As well,the Shannon indices of soil bacteria and fungi were greater in the fenced plot.Plant-soil changes profoundly affected the alpha-and beta-diversity of soil bacteria.Fence management also altered the soil microbial community structure,significantly increasing the relative abundances of Acidobacteriota(5.31%-8.99%),Chloroflexi(3.99%-5.58%),and Glomeromycota(1.37%-3.28%).The soil bacterial-fungal co-occurrence networks under fence management had higher complexity and connectivity.Based on functional predictions,fence management significantly increased the relative abundance of bacteria with nitrification and nitrate reduction functions and decreased the relative abundance of bacteria with nitrate and nitrite respiration functions.The relative abundances of ecologically functional fungi with arbuscular mycorrhizal fungi,ectomycorrhizal fungi,and saprotrophs also significantly increased under fence management.In addition,the differential functional groups of bacteria and fungi were closely related to plant-soil changes.The results of this study have significant positive implications for the ecological restoration and reconstruction of dry desert steppe and similar areas.

关键词： desert steppe fence management Caragana korshinskii soil physical-chemical property soil microorganism

Artificial Intelligence in the Oil and Gas Industry:Opportunities,Challenges,and Strategies

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China Oil & Gas 2024年第2期31卷 20-26页

作者： Wang Jinxiao Sun Qian li xinrong CNOOC Energy Economics Institute School of Economics and Management Tsinghua University Chinese Academy of Science and Technology for Development

Introduction The current new wave of the digital revolution is sweeping the world with unprecedented breadth and depth.With the acceleration of digital transformation,artificial intelligence(AI),which is known as the engine of the“Fourth Industrial Revolution”,is playing a significant role in driving the digital transformation and intelligent development of related industries,and generating substantial social and economic benefits.In the oil and gas industry,it has become an inevitable trend to utilize AI technology to achieve automatic data collection,real-time monitoring,intelligent production optimization,and smart decision-making.

关键词： utilize generating driving

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庚戌新军起义善后与广州舆论的“悼惜”风潮

史学月刊 2024年第2期 65-75页

作者：李欣荣中山大学历史学系广东广州510275

庚戌(1910年)广州新军起义,作为清末孙中山领导的第九次起义,载入辛亥革命的史册。吊诡的是,起义被镇压后,官方与绅、商、学界围绕事件性质与善后问题产生了激烈的意见冲突。广东当局公布革命党人的口供和物证,力证其为叛乱行动,并解散... 详细信息

庚戌(1910年)广州新军起义,作为清末孙中山领导的第九次起义,载入辛亥革命的史册。吊诡的是,起义被镇压后,官方与绅、商、学界围绕事件性质与善后问题产生了激烈的意见冲突。广东当局公布革命党人的口供和物证,力证其为叛乱行动,并解散涉事的七营全体士兵。以粤商自治会为首的多数舆论则认为这是粤省当局处置不善导致的兵变。特别是巡防营在镇压过程中军纪败坏,而由“良家子弟”组成的新军虽然失败但仍不愿扰民,引发“悼惜新军”的舆论风潮。可见粤省绅、商、学界对于革命态度暧昧,更重视保护本省与自身的权益。清廷在舆论压力下选择惩处镇压有功的粤省官吏,后者唯有掩盖新军既存问题直至皇朝倾覆,反映了筹备立宪语境下民意勃发,政局不稳,清廷却盲目推动新军建设的时代矛盾。

关键词：广州新军巡防营袁树勋粤商自治会

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基于科学的企业外部治理全过程模型研究

科研管理 2024年第2期45卷 165-175页

作者：方帅李欣融雷家骕中国地质大学(北京)经济管理学院北京100083 中国科学技术发展战略研究院博士后科研工作站北京100038 清华大学经济管理学院北京100084

基于科学的企业是由科学家主导或参与创建,从事基础科学研究,通过基础科学成果的应用开发和商业转化获取经济利益,并在此过程中做出补充性科学研究的企业。针对基于科学的企业外部治理的研究呈现碎片化特征,有必要对现有研究进行系统性... 详细信息

基于科学的企业是由科学家主导或参与创建,从事基础科学研究,通过基础科学成果的应用开发和商业转化获取经济利益,并在此过程中做出补充性科学研究的企业。针对基于科学的企业外部治理的研究呈现碎片化特征,有必要对现有研究进行系统性梳理和回顾。通过对相关文献检索和分析发现,由于基于科学的企业其特殊性,其外部治理框架相较于传统企业呈现出独特的外部治理视角:主要围绕传统的外部治理元素(政府规制、资本市场)和独特的外部治理元素(科技教育界行规)展开,因此本文着重深入关注这三类治理元素及其治理机制,以政府规制、资本市场、科技教育界行规为逻辑框架,对基于科学的企业外部治理机制涉及的元素、过程、治理效果及理论机制进行分析,全面回顾和总结了基于科学的企业外部治理研究现状和相关主题内容,归纳整合了基于科学的企业外部治理机制的全过程模型,并指出了未来的研究方向。本文丰富和拓展了基于科学的企业外部治理研究框架,为启发中国情境下基于科学的企业的外部治理理论与实践提供借鉴。

关键词：基于科学的企业外部治理政府规制资本市场科技教育界行规

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印花面料的边缘轮廓快速提取方法

纺织学报 2024年第5期45卷 165-173页

作者：文嘉琪李新荣冯文倩李瀚森天津工业大学机械工程学院天津300387 天津市现代机电装备技术重点实验室天津300387

工业协作型缝纫机器人代替操作工自动完成缝合是未来发展的必然趋势,但当前的工业协作型缝纫机器人难以快速精准地定位面料边缘轮廓信息,影响缝纫效率与缝纫质量。针对印花面料提出线下使用深度学习建立面料检测模型,线上调用面料检测... 详细信息

工业协作型缝纫机器人代替操作工自动完成缝合是未来发展的必然趋势,但当前的工业协作型缝纫机器人难以快速精准地定位面料边缘轮廓信息,影响缝纫效率与缝纫质量。针对印花面料提出线下使用深度学习建立面料检测模型,线上调用面料检测模型分割面料与背景并结合传统轮廓检测算法快速准确提取面料边缘轮廓的方法。首先,建立面料图像数据集,并通过卷积拆分和融合损失函数对VGG-UNet模型进行优化,将面料数据集输入至优化的VGG-UNet模型进行训练学习并构建最优面料检测模型;其次,利用最优面料检测模型分割面料与背景;然后,采用数学形态学算法对分割后的面料图像进行自适应开运算去除面料边缘的毛边;最后,利用Canny算子对去除毛边后的面料图像进行轮廓提取。实验结果表明,本文方法可较好去除面料毛边并快速精准提取印花面料的边缘轮廓,所提取的轮廓与面料边缘轮廓高度拟合,轮廓提取精度高于99%,轮廓提取时间仅需0.216 s。本文研究可为后续机器人的轨迹规划提供快速准确的坐标信息,提高缝合质量和效率,推进无人化、自动化缝合生产线的实现。

关键词：印花面料边缘轮廓提取机器视觉深度学习 VGG-UNet模型缝纫质量

Carbon fixation and influencing factors of biological soil crusts in a revegetated area of the Tengger Desert,northern China

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Journal of Arid Land 2014年第6期6卷 725-734页

作者： Lei HUANG ZhiShan ZHANG xinrong li Shapotou Desert Research and Experimental Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions of Gansu Province

Biological soil crusts （BSCs） are an important type of land cover in arid desert landscapes and play an important role in the carbon source-sink exchange within a desert system. In this study, two typical BSCs, moss crusts and algae crusts, were selected from a revegetated sandy area of the Tengger Desert in northern China, and the experiment was carried out over a 3-year period from January 2010 to November 2012. We obtained the effec- tive active wetting time to maintain the physiological activity of BSCs basing on continuous field measurements and previous laboratory studies on BSCs photosynthesis and respiration rates. And then we developed a BSCs carbon fixation model that is driven by soil moisture. The results indicated that moss crusts and algae crusts had significant effects on soil moisture and temperature dynamics by decreasing rainfall infiltration. The mean carbon fixation rates of moss and algae crusts were 0.21 and 0.13 g C/（m2.d）, respectively. The annual carbon fixations of moss crusts and algae crusts were 64.9 and 38.6 g C/（m2.a）, respectively, and the carbon fixation of non-rainfall water reached 11.6 g C/（m2.a）（30.2% of the total） and 8.8 g C/（m2.a）（43.6% of the total）, respectively. Finally, the model was tested and verified with continuous field observations. The data of the modeled and measured CO2 fluxes matched notably well. In desert regions, the carbon fixation is higher with high-frequency rainfall even the total amount of seasonal rainfall was the same.

关键词： moss crusts algae crusts soil moisture dynamics non-rainfall water effective wetting time

Patterns of shrub species richness and abundance in relation to environmental factors on the Alxa Plateau:Prerequisites for conserving shrub diversity in extreme arid desert regions

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Science China Earth Sciences 2009年第5期52卷 669-680页

作者： xinrong li HuiJuan Tan MingZhu He XinPing Wang XiaoJun li Shapotou Desert Research and Experiment Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Shrub species are considered the dominant plants in arid desert ecosystems,unlike in semiarid steppe zones or in grassland ecosystems.On the Alxa Plateau,northern China,sparse vegetation with cover ranging from 15% to 30% is characterized mainly by multifarious shrubs because herbaceous species are strongly restricted by the extreme drought climate,wind erosion,overgrazing and sand burial.Patterns in shrub species richness and species abundance in relation to environmental conditions were examined by DCA(detrended correspondence analysis) and interpreted by a biplot.The rela-tionships between species diversity and environmental factors were examined using regression analyses.Our results show that the distributions of the shrub species in response to environmental conditions can be grouped into four ecological types,corresponding with the biological traits of the shrubs and their responses to the gradients of soil texture and soil water content.Patterns in species richness and species abundance were mainly determined by the deeper soil water content,instead of the soil texture as hypothesized by numerous studies in semiarid grasslands.With exception of the deeper soil water content,soil organic matter and total N content were positively correlated with species abundance,while pH was negatively correlated with it.These findings imply that it is vital for cur-rent shrub diversity conservation to reduce agricultural water use in the middle reaches of the Heihe River,which supplies water for the lower reaches in the western parts of the plateau,and to reduce the amount of groundwater exploitation and urban and oasis water use,to increase the water supply from Helan Mountain to the eastern desert of the Alxa Plateau.

关键词： biodiversity conservation shrub species richness abundance Alxa Plateau desert ecosystems

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高校继续教育创新人才培养路径分析

中国成人教育 2024年第3期 35-41页

作者：李昕荣上海交通大学终身教育学院党委上海200240 上海市终身教育研究会上海200240

高校继续教育在终身学习型社会建设进程中具有引领示范作用,与本科生教育、研究生教育共同构成大学人才培养体系,为社会提供不同层次、有特色的高质量人才。以理论逻辑、历史逻辑和现实逻辑审视继续教育人才培养路径,采取多模态交叉组... 详细信息

高校继续教育在终身学习型社会建设进程中具有引领示范作用,与本科生教育、研究生教育共同构成大学人才培养体系,为社会提供不同层次、有特色的高质量人才。以理论逻辑、历史逻辑和现实逻辑审视继续教育人才培养路径,采取多模态交叉组合课程,走向非平衡与非线性教学模式,满足实践应用的前沿研究,探索我国继续教育在终身学习型社会背景下优化人才培养的共识度、耦合度、互动度和融合度。

关键词：高校继续教育人才培养课程体系

维普期刊数据库博看期刊

Soil water repellency and influencing factors of Nitraria tangutorun nebkhas at different succession stages

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Journal of Arid Land 2014年第3期6卷 300-310页

作者： HaoTian YANG xinrong li liChao liU YanHong GAO Gang li Rongliang JIA Shapotou Desert Research and Experiment Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Abstract： Soil water repellency （WR） is an important physical characteristic of soil surface. It is capable of largely influencing the hydrological and geomorphological processes of soil, as well as affecting the ecological processes of plants, such as growth and seed germination, and has thus been a hot topic in recent research around the world. In this paper, the capillary rise method was used to study the soil WR characteristics of Nitraria tangutorun nebkhas. Soil water repellencies at different succession stages of Nitraria tangutorun were investigated, and the relationships between soil WR and soil organic matter, total N, and total P, soil texture, pH, and concentrations of CO32, HCO3-, CI, SO42-, Na~, K~, Ca2~ and Mg2＋ were discussed. Soil WR may be demonstrated at the following nebkhas dune evolvement stages： extremely degraded〉degraded〉stabilized〉well developed〉newly developed〉quick sand. Apart from some soil at the bottom, the WR of other soils （crest and slope of dune） was found to be largest at the topsoil, and decreased as the soil depth increased. The results showed that multiple factors affected soil WR characteristics e.g. WR increased significantly as the contents of soil organic matter and total N increased, but did not change as the total P content increased. Soil texture was a key factor affecting soil WR; soil WR increased significantly as clay content increased, and decreased significantly as sand content increased. Low pH was shown to be more suitable for the occurrence of soil WR. Four cations （Ca2＋, Mg2＋, K＋ and Na＋） and two anions （CI and SO42） enhanced soil WR, while CO32-decreased it. HCO3- did not show any observable effect. Finally, we established a best-fit general linear model （GLM） between soil-air-water contact angle （CA） and influencing factors （CA=5.606 sand＋6.496 （clay and silt）-2.353 pH＋470.089 CQ2＋11.346 Na＋-407.707 Cl--14.245 SO42-＋0.734 total N-519.521 ）. It was concluded that all soils contain subcritical WR （0°〈CA〈90°）. The development and succession of Nitraria tanguto

关键词： hydrophobicity soil-air-water contact angle capillary rise method Nitraria tangutorun nebkhas vegetation succession stage