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Correlation Between CO_2 Efflux and Net Nitrogen Mineralization and Its Response to External C or N Supply in an Alpine Meadow Soil

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Pedosphere 2011年第5期21卷 666-675页

作者： SONG Ming-Hua JIANG Jing xu xing-liang SHI Pei-Li Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 (China) State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) Graduate University of Chinese Academy of Sciences Beijing 100049 (China)

In nutrient-limited alpine meadows,nitrogen(N) mineralization is prior to soil microbial immobilization;therefore,increased mineral N supply would be most likely immobilized by soil microbes due to nutrient shortage in alpine *** addition,low temperature in alpine meadows might be one of the primary factors limiting soil organic matter decomposition and thus N mineralization.A laboratory incubation experiment was performed using an alpine meadow soil from the Tibetan *** levels of NH4NO3(N) or glucose(C) were added,with a blank without addition of C or N as the control,before incubation at 5,15,or 25 ℃ for 28 ***2 efflux was measured during the 28-d incubation,and the mineral N was measured at the beginning and end of the incubation,in order to test two hypotheses:1) net N mineralization is negatively correlated with CO2 efflux for the control and 2) the external labile N or C supply will shift the negative correlation to *** results showed a negative correlation between CO2 efflux and net N immobilization in the *** inorganic N supply did not change the negative *** external labile C supply shifted the linear correlation from negative to positive under the low C addition ***,under the high C level,no correlation was *** suggested that the correlation of CO2 efflux to net N mineralization strongly depend on soil labile C and C:N ratio regardless of *** research should focus on the effects of the types and the amount of litter components on interactions of C and N during soil organic matter decomposition.

关键词： C:N ratio inorganic N labile C organic matter temperature

Alterations to biological soil crusts with alpine meadow retrogressive succession affect seeds germination of three plant species

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Journal of Mountain Science 2016年第11期13卷 1995-2005页

作者： LI Yi-kang OUYANG Jing-zheng LIN Li xu xing-liang ZHANG Fa-wei DU Yan-gong LIU Shu-li CAO Guang-min HAN Fa Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810001China University of Chinese Academy of Sciences Beijing 100049China Institute of Geographic Sciences&Natural Resources Research the Chinese Academy of SciencesBeijing 100101China Liancheng National Nature Reserve of Gansu Province Yongdeng Country 730000China

Biological soil crusts(BSCs) are the important components of alpine meadow *** extent and morphology of BSCs vary greatly with alpine meadow retrogressive succession due to grazing *** is significant interest in impacts of crust composition on plant seed germination,especial l y in(semi-) arid ***,little is known about the influences of BSCs,and their associations with alpine meadow succession,on germination of typical alpine meadow vascular plant *** a full factorial common-gardenexperiment,we studied effects of:(1) crust type,(2) seed position,and(3) surface texture on seed *** chose three typical alpine meadow plant species(*** pratensis,Tibetia himalaica and Potentillen nivea),which belonged to different functional groups(graminoids,legumes,and forbs) and play important roles in all alpine meadow succession *** type and seed position influenced seed germination,and the inhibitory effects of BSCs depended on the crust type and seed species *** major factors influencing seed germination were BSC type,seed position,soil texture,and the interactions between BSC type and seed position; species and seed position; species andsurface texture; and species,crust type,and surface *** crust significantly inhibited germination of all *** position also had a significant effect on seed germination(p < 0.001).Fewer seedlings germinated on the surface than below the surface,this was especially true for *** within cyanobacteria and lichen *** germination rates of *** on the soil surface were significantly correlated with plant occurrence frequency within the alpine meadow *** poor correlation for the other two species is possibly that they are *** results clearly demonstrated that BSCs can be biological filters during seed germination,depending on the BSC succession *** their influences on seed germination,BSCs can strongly

关键词： Crust type Seed position Microenvironment Germination Tibetan Plateau Vascular plants

Effects of Temperature and Water Saturation on CO_2 Production and Nitrogen Mineralization in Alpine Wetland Soils

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Pedosphere 2009年第1期19卷 71-77页

作者： GAO Jun-Qin OUYANG Hua xu xing-liang ZHOU Cai-Ping ZHANG Feng Beijing Forestry University Beijing 100083 （China） 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）

Relationships between carbon (C) production and nitrogen (N) mineralization were investigated in two alpine wetland soils of the Tibetan Plateau using laboratory incubation under different temperatures (5, 15, 25, and 35 ℃) and water saturation (noninundation and inundation). A significant positive relationship was found between CO2 production and N mineralization under increasing temperatures from 5 to 35 ℃ with the same water saturation condition in the marsh soil (r2 > 0.49, P 0.38, P 0.70, P 0.61, P < 0.013). In conclusion, temperatures and water saturation could regulate the relationship between CO2 production and net N mineralization in the Tibetan alpine marsh and peat soils.

关键词： CO2 production N mineralization temperature water saturation wetland

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富水条件下软岩巷道变形特征与过程控制研究

中国矿业大学学报 2007年第3期36卷 298-302页

作者：许兴亮张农中国矿业大学能源与安全工程学院江苏徐州221116

富水条件下泥质软岩巷道破坏及稳定性机制比一般软岩巷道更复杂,不仅需要采用多种复合支护控制围岩非线性大变形,还必须进一步控制其泥化进程.针对此情况,提出了动态过程控制的支护原理,采用预拉力锚杆、锚索、桁架和围岩滞后注浆堵水... 详细信息

富水条件下泥质软岩巷道破坏及稳定性机制比一般软岩巷道更复杂,不仅需要采用多种复合支护控制围岩非线性大变形,还必须进一步控制其泥化进程.针对此情况,提出了动态过程控制的支护原理,采用预拉力锚杆、锚索、桁架和围岩滞后注浆堵水加固相结合的全过程控制围岩技术.结果表明,在成功阻断泥化诱因"水"之后,高强预应力锚杆组合支护体系可有效控制巷道变形,避免泥化导致随后的锚固失效.此技术在淮北桃园煤矿裂隙水患严重的三软煤巷支护中取得成功.

关键词：富水条件泥质软岩变形特征过程控制

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不同密度下拟南芥的亲缘选择

生态学杂志 2016年第12期35卷 3299-3305页

作者：李洁王静徐兴良梁涛中国科学院地理科学与资源研究所陆地表层格局与模拟重点实验室北京100010 中国科学院大学北京100049 国家林业局西北林业调查规划设计院西安710048

亲缘选择理论认为亲缘个体之间通过亲缘认知而相互合作以增加其适合度。前期的相关研究证实了一些植物物种之间具有亲缘选择作用,而且不同物种对亲缘选择的响应方式各有差异。但是,现有的试验物种较少,且未考虑其他环境因子的影响。为... 详细信息

亲缘选择理论认为亲缘个体之间通过亲缘认知而相互合作以增加其适合度。前期的相关研究证实了一些植物物种之间具有亲缘选择作用,而且不同物种对亲缘选择的响应方式各有差异。但是,现有的试验物种较少,且未考虑其他环境因子的影响。为了验证拟南芥(Arabidopsis thaliana)不同生态型对亲缘选择的响应方式,本试验选取3个拟南芥生态型[Columbia(Col)、Landsbergerecta(Ler)和Wassileskijia(Ws)]作为研究对象,在3种密度条件下,通过测度植物表型特征(株高、莲座面积、叶面积和种子数等)和各构件生物量特征(根、茎、叶和种子生物量)在亲缘处理组和非亲缘组的差异,来探索密度对亲缘选择结果的影响。结果表明,拟南芥各生态型亲缘组与非亲缘组差异主要表现在地上部分,而地下部分在亲缘和非亲缘组并没有显著差异;3种生态型拟南芥对亲缘选择的响应方式不同,Col主要表现在种子生物量上,Ler主要表现在叶和茎生物量上,Ws主要表现在种子和茎生物量上;拟南芥不同生态型对亲缘选择的响应方式依赖于种植密度,密度是影响拟南芥亲缘选择表现的重要因素。

关键词：亲缘选择表型特征生物量根系分配密度

Superhydrophobic and corrosion-resistant siloxane-modified MgAl-LDHs coatings on magnesium alloy prepared under mild conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 450-463页

作者： Wenxi Zhang Zhangzelong Zhuo Dan xu liang Wu Zhihui Xie Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province College of Chemistry and Chemical EngineeringChina West Normal UniversityNanchong 637002China College of Materials Science and Engineering/National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China

We have developed a superhydrophobic and corrosion-resistant LDH-W/PFDTMS composite coating on the surface of Mg *** composite comprised a tungstate-intercalated(LDH-W)underlayer that was grown at low temperature(relative to hydrothermal reaction conditions)under atmospheric pressure and an outer polysiloxane layer created from a solution containing perfluorodecyltrimethoxysilane(PFDTMS)using a simple immersion *** successful intercalation of tungstate into the LDH phase and the following formation of the polysiloxane layer were confirmed through X-ray diffraction(XRD),Fourier transform infrared(FTIR)spectroscopy,and X-ray photoelectron spectroscopy(XPS).The corrosion resistance of the LDH-W film,both before and after the PFDTMS modification,was evaluated using electrochemical impedance spectroscopy(EIS),Tafel curves,and immersion *** results showed that Mg coated with LDH-W/PFDTMS exhibited significantly enhanced corrosion protection compared to the unmodified LDHW film,with no apparent signs of corrosion after exposure to 3.5wt%NaCl solution for 15 ***,the LDH-W/PFDTMS coating demonstrated superior superhydrophobicity and self-cleaning properties against water and several common beverages,as confirmed by static contact angle and water-repellency *** results offer valuable insights into preparing superhydrophobic and corrosion-resistant LDH-based composite coatings on Mg alloy surfaces under relatively mild reaction conditions.

关键词： Mg alloy corrosion coating layered double hydroxide

基于生态系统演变机理的生态系统脆弱性、适应性与突变理论

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应用生态学报 2022年第3期33卷 623-628页

作者：徐兴良于贵瑞中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室北京100101 中国科学院大学资源与环境学院北京100049

随着气候变化影响广度与深度的增加,生态系统脆弱性、适应性与突变理论逐渐被广泛应用到生态学研究领域中,探讨和评估各类生态系统对气候变化的敏感性、脆弱性和适应性,可谋求更好的方式来应对气候变化对区域生态系统带来的深远影响,服... 详细信息

随着气候变化影响广度与深度的增加,生态系统脆弱性、适应性与突变理论逐渐被广泛应用到生态学研究领域中,探讨和评估各类生态系统对气候变化的敏感性、脆弱性和适应性,可谋求更好的方式来应对气候变化对区域生态系统带来的深远影响,服务于国家生态系统可持续管理及生态安全建设。虽然相关研究已获取许多进展,区分了气候敏感区和某些生态系统的潜在转折点,但是学界对这些概念尚存在多种的理解和阐释,这一定程度上影响了相关理论的进一步发展与应用。针对此,本文梳理了相关概念的发展历程,并从生态系统生态学角度深入剖析了这些概念内涵,进一步提出了基于生态系统演变机理的生态系统脆弱性和适应性及突变理论框架和相应的计算方法,以期推动生态系统脆弱性、适应性与突变理论深入发展。

关键词：生态系统脆弱性生态系统适应性生态系统突变生态系统演替气候变化

综放工作面煤柱尺寸对顶板破断结构及裂隙发育的影响规律

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煤炭学报 2015年第4期40卷 850-855页

作者：许兴亮魏灏田素川张蓓中国矿业大学矿业工程学院江苏徐州221116 中国矿业大学煤炭资源与安全开采国家重点实验室江苏徐州221116 中国矿业大学深部煤炭资源开采教育部重点实验室江苏徐州221116

煤层开采后基本顶破断结构直接影响上覆岩层裂隙区的范围和发育程度,运用理论分析和数值模拟相结合的方法,对不同煤柱条件下基本顶破断结构以及由此带来的顶板裂隙发育区演化规律进行了研究。上工作面侧向破断"三铰拱"结构使下工作面基... 详细信息

煤层开采后基本顶破断结构直接影响上覆岩层裂隙区的范围和发育程度,运用理论分析和数值模拟相结合的方法,对不同煤柱条件下基本顶破断结构以及由此带来的顶板裂隙发育区演化规律进行了研究。上工作面侧向破断"三铰拱"结构使下工作面基本顶破断由固支悬臂梁结构变为铰支结构,煤柱两侧形成不对称裂隙发育区。研究结果表明:中小煤柱时,岩块铰接回转,岩块长度大于基本顶悬臂极限断裂长度且随煤柱尺寸增加逐渐增加,裂隙发育区范围随之增加;大煤柱时,下工作面基本顶破断超出上工作面侧向结构影响范围外,岩块长度不变。回转角度由岩块长度和下沉量共同决定,并通过理论分析得到了相应的计算公式。

关键词：基本顶结构煤柱尺寸演化规律裂隙发育区

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不同组构砂岩微观破坏特征分析

东北大学学报（自然科学版） 2024年第4期45卷 584-591页

作者：孙大增赵文许兴亮王鑫东北大学资源与土木工程学院辽宁沈阳110819 中国矿业大学煤炭资源与安全开采国家重点实验室江苏徐州221116

为了研究不同组构砂岩宏观-微观破坏特征的内在联系,对香花岭矿区三种砂岩开展物相分析、沉积相判别及单轴压缩和剪切试验,观察微观结构差异.研究结果表明:陆相沉积石英砂岩抗压强度最大,长石砂岩次之,海相沉积海绿石砂岩最小;单轴压缩... 详细信息

为了研究不同组构砂岩宏观-微观破坏特征的内在联系,对香花岭矿区三种砂岩开展物相分析、沉积相判别及单轴压缩和剪切试验,观察微观结构差异.研究结果表明:陆相沉积石英砂岩抗压强度最大,长石砂岩次之,海相沉积海绿石砂岩最小;单轴压缩试验宏观上石英砂岩、长石砂岩发生脆性破坏,而海绿石砂岩呈现出具有软化特性的延性破坏,微观上石英砂岩发生沿晶破坏,断面平整,长石砂岩发生沿晶和穿晶破坏,断面呈小扇贝状,表面附着少量碎屑,海绿石砂岩断面呈平板-花团复合状,晶粒破碎且擦痕明显,晶粒、胶结物质及结构弱面共同控制破坏特征;剪切试验微观上石英砂岩先发生沿晶破坏后发生穿晶破坏,断面不平整、擦痕及碎屑多,长石砂岩以沿晶破坏为主伴随穿晶破坏,断面部分平整、擦痕及碎屑较多,海绿石砂岩同时发生沿晶破坏和穿晶破坏,断面平整、几乎无擦痕和碎屑,砂岩微观破坏特征受晶粒和晶间胶结物质强度的共同影响.

关键词：砂岩矿物组成微观结构破坏特征强度

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