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Mechanism of plant-soil feedback in a degraded alpine grassland on the Tibetan Plateau

Journal of Plant Ecology 2024年第2期17卷 188-199页

作者： tiancai zhou Jian Sun Peili Shi Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Tibetan Plateau Earth System Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Biodiversity and Environment on the Qinghai-Tibet Plateau Ministry of EducationLhasa 850011China Tibet Research Academy of Eco-environmental Sciences Lhasa 850000China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Although biotic and abiotic factors have been confirmed to be critical factors that affect community dynamics,their interactive effects have yet to be fully considered in grassland ***,we tested how soil nutrients and microbes regulated plant-soil feedback(PSF)in a degraded alpine *** results indicated that soil total carbon(STC;from 17.66 to 12.55 g/kg)and total nitrogen(STN;from 3.16 to 2.74 g/kg)exhibited significant(P<0.05)decrease from non-degraded(ND)to severely degraded(SD).Despite higher nutrients in ND soil generating significantly(P<0.05)positive PSF(0.52)on monocots growth when the soil was sterilized,a high proportion of pathogens(36%)in ND non-sterilized soil resulted in a strong negative PSF on *** contrast,the higher phenotypic plasticity of dicots coupled with a higher abundance of mutualists and saprophytes(70%)strongly promoted their survival and growth in SD with infertile *** findings identified a novel mechanism that there was a functional group shift from monocots with higher vulnerability to soil pathogens in the ND fertile soil to dicots with higher dependence on nutritional mutualists in the degraded infertile *** emerging irreversible eco-evolutionary in PSF after degradation might cause a predicament for the restoration of degraded grassland.

关键词： plant-soil feedback plant function groups degradation alpine grassland Tibetan Plateau

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青藏高原高寒草地土壤酶活性海拔地带性特征

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生态学报 2024年第1期44卷 405-415页

作者：霍皇煜米琦周天财李洋张建香陈俊合汪亚峰孙建青藏高原地球系统与资源环境全国重点实验室中国科学院青藏高原研究所北京100101 中国科学院大学资源与环境学院北京100049 兰州大学生态学院兰州730000 兰州大学资源环境学院兰州730000

土壤酶是土壤生态系统中具有催化功能的一类蛋白质,由植物根系分泌物、微生物和动植物残体释放到土壤中,参与了土壤中所有的生物化学过程,其活性的大小可以灵敏地反应土壤中生化反应的方向和强度。青藏高原因海拔高和气候寒冷,被认为是... 详细信息

土壤酶是土壤生态系统中具有催化功能的一类蛋白质,由植物根系分泌物、微生物和动植物残体释放到土壤中,参与了土壤中所有的生物化学过程,其活性的大小可以灵敏地反应土壤中生化反应的方向和强度。青藏高原因海拔高和气候寒冷,被认为是气候变化的敏感区和脆弱区。全球气候变化使土壤酶活性受到强烈的影响,这些影响可能使土壤的质量发生改变,进而对青藏高原高寒草地植被生产力产生一定影响。土壤酶在生态系统物质循环和能量流动中起着关键作用,其格局、功能和转换过程已被广泛的研究,但高寒草地生态系统土壤酶活性的海拔地带性特征还需深入探讨。因此,以青藏高原高寒草地为研究对象,将土壤酶活性海拔梯度研究从站点尺度拓展到样带尺度,分析了与土壤碳循环密切相关的土壤β-1,4-葡萄糖苷酶(βG)、与土壤氮循环密切相关的土壤N-乙酰-β氨基葡萄糖苷酶(NAG)、土壤亮氨酸肌肽酶(LAP)以及与土壤磷循环密切相关的土壤碱性磷酸酶(ALP)的海拔地带性,进一步明晰其主要驱动因子。结果表明:(1)ALP和βG活性在海拔梯度上,展现出显著分异,在约为3546 m和3364 m出现拐点,且低海拔显著高于高海拔(P<0.01)。而NAG和LAP的活性与海拔无显著关系。(2)高低海拔模式下,ALP活性均与年平均降水量显著相关(P<0.01),而不受年平均温度的影响。高海拔模式下,βG活性受降水的影响;低海拔模式下,气候影响不明显。综合而言,海拔变化引起的温度和降水变化会直接或间接地影响土壤酶活性,其中降水是影响青藏高原高寒草地土壤酶活性的关键因子之一,这种适应性的改变使土壤酶能够在不同的环境条件下适应并发挥其功能,从而影响着土壤生态系统的物质循环和能量转化过程。研究结果可以评估不同海拔地带土壤的养分转化、有机质分解和循环等生态系统功能,为生态系统管理和保护提供科学依据,对理解高寒草地生物地球化学循环过程和机制具有重要意义。

关键词：青藏高原高寒草地土壤酶活性垂直地带性降水

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Dynamics and controls of ecosystem multiserviceability across the Qingzang Plateau

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Geography and Sustainability 2023年第4期4卷 318-328页

作者： Ruowei Li Guodong Han Jian Sun tiancai zhou Junhe Chen Wen He Yi Wang College of Grassland Resources and EnvironmentKey Laboratory of Grassland Resources of the Ministry of Education of Chin1Inner Mongolia Agricultural UniversityHohhot 010019China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Institute for Disaster Management and Reconstruction Sichuan University-Hongkong Polytechnic UniversityChengdu 610207China School of Life Sciences Sun Yat-sen UniversityGuangzhou 510275China

Ecosystem multiserviceability(EMS),a comprehensive and significant ecological indicator,reflects the capacity of ecosystems to offer multiple services *** climate change and human activity are continu-ously altering ecosystem functions,services,and ***,numerous studies have only focused on one or a few ecosystem services,rarely taking into account spatial-temporal distribution and drivers of EMS on behalf of different *** calculated EMS including pastoralist(PA),environmental protection agency(EPA),bio-diversity conservation agency(BCA),and climate change mitigation agency(CCMA)using grassland production,habitat quality,water conservation,and carbon ***,the effects of geographical features,climate factors,and human activities on spatial-temporal patterns of EMS were *** result indicated that EMS showed a decreasing tendency from the southeast to northwest on the Qingzang Plateau(QZP).Meanwhile,there were no obvious fluctuations in four simulated scenarios(PA,EPA,BCA and CCMA)among different vegetation types during 2000 to ***,EMS of all simulated scenarios decreased in the alpine steppe ecosystem,but negligible changes were found in other ecosystems from 2015 to ***,the relative importance of precipitation in annual mean value(from 2000 to 2020)of PA,EPA,BCA and CCMA were 0.13,0.11,0.30 and 0.19,***,precipitation played the dominant role on the dynamics of EMS,followed by elevation and human *** findings highlighted that understanding the patterns and drivers of EMS could provide a reference for the regional management and maintenance of ecosystem stability on QZP.

关键词： Ecosystem multiserviceability Qingzang Plateau Spatial-temporal patterns Drivers

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优势种对藏北草原群落稳定性具有主导作用

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Journal of Plant Ecology 2023年第3期16卷 165-176页

作者： Ge Hou Peili Shi tiancai zhou Jian Sun Ning Zong Minghua Song Xianzhou Zhang Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China

优势种作为群落动态和生态系统的重要驱动因素,对生物条件以及与其他物种的相互作用具有强烈的影响,这一现象在高寒草地生态系统中尤其明显。然而,不同生态系统中优势种对群落稳定性的影响作用却知之甚少。本文研究了藏北草原4大高寒草... 详细信息

优势种作为群落动态和生态系统的重要驱动因素,对生物条件以及与其他物种的相互作用具有强烈的影响,这一现象在高寒草地生态系统中尤其明显。然而,不同生态系统中优势种对群落稳定性的影响作用却知之甚少。本文研究了藏北草原4大高寒草地(高寒草甸、高寒草甸草原、高寒草原和高寒荒漠草原)地上生产力的时间稳定性(2014-2020年)和群落稳定性机制,并分析了群落特征和物种组成的变化。研究结果表明,高寒草甸的群落稳定性显著高于其他3种草地。这种差异主要归因于高寒草甸较高的补偿效应和选择效应。此外,优势种通过增加其稳定性和异步性来维持群落稳定性。这些研究结果表明了优势种作为群落的基础物种,可能在塑造高寒草原群落稳定性方面发挥着主导作用。因此,在日益加剧的环境波动下,保护优势种对于脆弱生态系统稳定生态系统功能至关重要。

关键词：群落稳定性物种丰富度优势种补偿效应选择效应

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Nonlinear Flap-Wise Vibration Characteristics ofWind Turbine Blades Based onMulti-Scale AnalysisMethod

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Energy Engineering 2024年第2期121卷 483-498页

作者： Qifa Lang Yuqiao Zheng tiancai Cui Chenglong Shi Heyu Zhang School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou730050China

This work presents a novel approach to achieve nonlinear vibration response based on the Hamilton *** chose the 5-MW reference wind turbine which was established by the National Renewable Energy Laboratory(NREL),to research the effects of the nonlinear flap-wise vibration *** turbine wheel is simplified by treating the blade of a wind turbine as an Euler-Bernoulli beam,and the nonlinear flap-wise vibration characteristics of the wind turbine blades are discussed based on the simplification ***,the blade’s large-deflection flap-wise vibration governing equation is established by considering the nonlinear term involving the centrifugal ***,it is truncated by the Galerkin method and analyzed semi-analytically using the multi-scale analysis method,and numerical simulations are carried out to compare the simulation results of finite elements with the numerical simulation results using Campbell diagram analysis of blade *** results indicated that the rotational speed of the impeller has a significant impact on blade *** the wheel speed of 12.1 rpm and excitation amplitude of 1.23 the maximum displacement amplitude of the blade has increased from 0.72 to *** the amplitude-frequency curve,it can be seen that the multi-peak characteristic of blade amplitude frequency is under centrifugal *** phase trajectories in blade nonlinear vibration,exhibiting periodic motion characteristics,are found through phase diagrams and Poincare section diagrams.

关键词： Wind turbine blades nonlinear vibration Galerkin method multi-scales method

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Considerations of Forest Distribution and Native Tree Species for Afforestation in the High Altitudes on the Eastern Tibetan Plateau

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Journal of Resources and Ecology 2022年第1期13卷 100-106页

作者： SHI Peili ZHENG Lili zhou tiancai HOU Ge ZHAO Guangshuai Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences andNatural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China School of Life Science Taizhou UniversityTaizhouZhejiang 318000China China National Forestry-Grassland Economics and Development Research Center National Forestry and Grassland AdministrationBeijing 100714China

Forests are the main components of terrestrial ecosystems and play an important role in the protection and construction of the national ecological security barrier. For a long time, China’s large-scale afforestation had been practiced in areas with rainfall higher than the 400 mm threshold, but the issue of afforestation in high altitudes on the Tibetan Plateau remains elusive in both practical experience and theoretical exploration. It is worth thinking further about what principles should be followed in the selection of tree species and suitable altitudes for afforestation in high-altitude areas, as well as what experiences and lessons of previous afforestation efforts should be applied in high-altitude areas. As per the law of vegetation zonal distribution, this paper argues that afforestation at high altitudes should comply with the principle of vegetation zonal distribution and the low temperature limitation,and points out that afforestation is feasible only within the forest distribution area and below the altitudes of climate timberlines. Furthermore, we demonstrate the potential spatial areas of afforestation, and determine the local tree species that may be used for afforestation based on the existing problems of afforestation in eastern Tibet. In summary, afforestation in high-altitude areas of the eastern Tibetan Plateau must comply with the law of zonal vegetation distribution, focus on the upper limit of altitude and the selection of suitable tree species, and adopt only suitable native tree species.

关键词： eastern Tibetan Plateau natural forest distribution climatic treeline low-temperature limitation afforestation upper limit afforestation species selection

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Friction reactions induced by selective hydrogenation of textured surface under lubricant conditions

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Friction 2024年第1期12卷 174-184页

作者： Naizhou DU Xubing WEI Xiaowei LI Zan CHEN Shiqi LU Jiaqing DING Cunao FENG Kai CHEN Jianghao QIAO Dekun ZHANG Kwang-Ryeol LEE tiancai ZHANG School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo 315201China Computational Science Center Korea Institute of Science and TechnologySeoul 136-791Republic of Korea Technology Development Department Shipbuilding Technology Research InstituteShanghai 200032China

The passivation of hydrogen atoms and the conformation of textured surfaces under oil-lubricated conditions are effective strategies to obtain amorphous carbon(a-C)films with extremely low *** is critical to understanding the influence mechanism of selective surface hydrogenation on the tribological behaviors of textured a-C film under oil-lubricated *** particular,the interactions of hydrogen atoms and lubricants are confusing,which is enslaved to the in situ characterization *** reactive molecular dynamics(RMD)simulations were conducted to analyze the friction response of textured a-C films with selective hydrogenation surfaces under oil-lubricated *** results indicate that the existence of hydrogen atoms on specific bump sites significantly decreases the friction coefficient(μ)of textured a-C film,which is highly dependent on the surface hydrogen *** repulsion between hydrogen atoms and lubricant molecules prompts the formation of a dense lubricant film on the surface of the mating ***,with the enhancement of the surface hydrogen content,the passivation of the friction interface and the repulsion between hydrogen atoms and lubricants play dominant roles in reducing the friction coefficient instead of hydrodynamic lubrication.

关键词： textured amorphous carbon(a-C) selective hydrogenation oil lubrication friction mechanism reactive molecular dynamics(RMD)

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Studies of Primary Angle Qosure Glaucoma in China

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眼科学报 1997年第3期13卷 120-124页

作者： Ningli Wang, Wenbin zhou, tiancai Ye, Qiang Yu, Mingying Lai, Meihua LeZhongshan Ophthalmic Center, Sun Yat-sen University of Medical Sciences, Guangzhou 510060, China

The resent researches on primary angle closure glaucoma (PACG) in China were reviewed. The prevalence of PACG (0.41%) in chinese is between the Caucasian and Eskimos, and chronic type is the dominant type in PACG. However, with the economic development and medical care improvements, the prevalence condition of PACG may change; several researches discovered that the mechanism of PACG, especially the chronic type, is not only because of pupil-blocking but also closely related to the mechanism of crowding of peripheral iris and the anterior location of the ciliary body. We supposed that PACG can be divided into several subtypes based on this machnism. Also, we believe that the use of ultrasound biomicroscopy (UBM) and ophthalmic laser in China has promoted the research of PACG and improved the level of prevention and treatment of PACG. Eye Science 1997; 13 : 120- 124.

关键词：闭角型青光眼初期中国多频生物显微

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青藏高原东缘沙化草甸植物氮磷的分配和耦合特征

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草业科学 2021年第2期38卷 209-220页

作者：刘天源周天财孙建王毅叶冲冲中国科学院地理科学与资源研究所北京100101 中国科学院大学资源与环境学院北京100190 成都理工大学地球科学学院四川成都610059 西南石油大学土木工程与建筑学院四川成都610500

植物氮、磷元素及其耦合关系对揭示植物群落变化乃至生态系统的功能与过程具有重要意义。本研究以青藏高原东部高寒草甸为研究对象,分析沙化胁迫下植物地上、地下部分的氮、磷含量与氮磷比的变化特征、分配差异及影响因素。结果表明:(1... 详细信息

植物氮、磷元素及其耦合关系对揭示植物群落变化乃至生态系统的功能与过程具有重要意义。本研究以青藏高原东部高寒草甸为研究对象,分析沙化胁迫下植物地上、地下部分的氮、磷含量与氮磷比的变化特征、分配差异及影响因素。结果表明:(1)植物地上部分的氮含量(平均值为15.3 mg·g^(−1))和氮磷比(平均值为5.2)整体低于地下部分的氮含量(平均值为28.2 mg·g^(−1))和氮磷比(平均值为12.5);随着沙化程度加剧,植物地上和地下部分的氮含量呈先升高后下降的趋势,而植物地上和地下部分的磷含量无明显变化趋势。(2)植物地上和地下部分普遍受到氮限制,氮、磷元素之间耦合关系在沙化胁迫下几乎没有协同性。(3)土壤含水量是影响植物地上和地下部分氮、磷含量的关键因素,植物地上和地下部分都会提高自身氮、磷含量以应对土壤水分降低的胁迫。在全球草地沙化的严峻形势下,本研究将为环境胁迫下植物的生存策略及其驱动机制提供理论参考。

关键词：沙化高寒草地植物氮磷生态化学计量土壤水分

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1984-2013年青藏高原土壤侵蚀时空变化特征

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应用与环境生物学报 2018年第2期24卷 245-253页

作者：康琳琦周天财干友民孙建王金牛四川农业大学动物科技学院成都611130 中国科学院地理科学与资源研究所生态网络观测与模拟重点实验室北京100101 成都理工大学地球科学学院成都610059 中国科学院成都生物所成都610041

土壤侵蚀严重威胁着区域生态安全与社会经济的发展乃至人类的共同福祉. 采用土壤侵蚀模型（RUSLE）得到青藏高原1984-2013年的土壤侵蚀情况，并分析土壤侵蚀强度的时空变化特征，探讨不同生态系统土壤侵蚀的变化特征及原因. 结果表明，1... 详细信息

土壤侵蚀严重威胁着区域生态安全与社会经济的发展乃至人类的共同福祉. 采用土壤侵蚀模型（RUSLE）得到青藏高原1984-2013年的土壤侵蚀情况，并分析土壤侵蚀强度的时空变化特征，探讨不同生态系统土壤侵蚀的变化特征及原因. 结果表明，1984-2013年青藏高原的土壤侵蚀量逐年波动变化，土壤侵蚀强度由南向北逐渐减弱，剧烈侵蚀主要分布在青藏高原南部（日喀则地区、拉萨市、昌都地区和山南北部地区）. 其中灌木、高寒草甸和稀疏植被生态系统侵蚀强度较大；土壤侵蚀量最大的是高寒草甸生态系统（2.17 ×10^10 t），其次是高寒草原（1.59 ×10^10 t）和稀疏植被生态系统（1.30 ×10^10 t）. 海拔3 000-4 000 m的土壤侵蚀强度最大，但土壤侵蚀量最大的是海拔4 000-5 000 m的地区. 30年里，研究区主要生态系统土壤侵蚀量有所减少（-1.78 ×10^8 t/a）. 其中，土壤侵蚀增加的区域主要包括羌塘高原南部地区和柴达木盆地外围地区；明显减少区域则分布于横断山脉—喜马拉雅山脉中部地区. 研究区主要植被生态系统覆盖度的增加有利于减少土壤侵蚀，但降雨量的改变主导了土壤侵蚀的变化. 降雨量增加导致低覆盖度且脆弱的高寒草原生态系统土壤侵蚀明显增强（增加量为1.19 ×10^8 t/a）；森林和灌木生态系统由于稳定性较高且降雨量明显减少，土壤侵蚀减弱（减少量分别为-0.77 ×10^8 t/a和-1.65 ×10^8 t/a）；稀疏植被系统土壤侵蚀量因降雨量的略微减少而少量减少（-0.44 ×10^8 t/a）；虽然高寒草甸生态系统降雨量明显增加，但其较高的植被覆盖度在一定程度上削弱了降雨侵蚀力的变化，土壤侵蚀量有所减少（-0.11 ×10^8 t/a）. 本研究揭示了青藏高原土壤侵蚀较为严重的地区、海拔及生态系统，分析了不同生态系统土壤侵蚀量变化可能的原因，可为水土流失的科学治理提供基础数据和理论参考. （图6 表4 参45）

关键词：修正通用土壤流失方程(RUSLE) 土壤侵蚀时空变化生态系统青藏高原

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