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Soil and Root Respiration Under Elevated CO_2 Concentrations During Seedling Growth of Pinus sylvestris ***

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Pedosphere 2007年第5期17卷 660-665页

作者： LIU Ying han shi-jie ZHOU Yu-Mei LI Xue-Feng College of Resource Science and Papermaking Engineering South China University of Technology Guangzhou 510640 （China） Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China）

The objectives of this study were to investigate the effect of higher CO2 concentrations （500 and 700 μmol mol^-1） in atmosphere on total soil respiration and the contribution of root respiration to total soil respiration during seedling growth of Pinus sylvestris vat. sylvestriformis. During the four growing seasons （May-October） from 1999 to 2003, the seedlings were exposed to elevated concentrations of CO2 in open-top chambers. The total soil respiration and contribution of root respiration were measured using an LI-6400-09 soil CO2 flux chamber on June 15 and October 8, 2003. To separate root respiration from total soil respiration, three PVC cylinders were inserted approximately 30 cm deep into the soil in each chamber. There were marked diurnal changes in air and soil temperatures on June 15. Both the total soil respiration and the soil respiration without roots showed a strong diurnal pattern, increasing from before sunrise to about 14：00 in the afternoon and then decreasing before the next sunrise. No increase in the mean total soil respiration and mean soil respiration with roots severed was observed under the elevated CO2 treatments on June 15, 2003, as compared to the open field and control chamber with ambient CO2. However, on October 8, 2003, the total soil respiration and soil respiration with roots severed in the open field were lower than those in the control and elevated CO2 chambers. The mean contribution of root respiration measured on June 15, 2003, ranged from 8.3% to 30.5% and on October 8, 2003, from 20.6% to 48.6%.

关键词： contribution of root respiration elevated CO2 concentration total soil respiration

Carbon and Nitrogen Transformations in Surface Soils Under Ermans Birch and Dark Coniferous Forests

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Pedosphere 2009年第2期19卷 230-237页

作者： DENG Xiao-Wen han shi-jie HU Yan-Ling ZHOU Yu-Mei Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Tianjin Academy of Environmental Sciences Tianjin 300191 China

Soil samples were taken from an Ermans birch （Betula ermanii）-dark coniferous forest （Picea jezoensis and Abies nephrolepis） ecotone growing on volcanic ejecta in the northern slope of Changbai Mountains of Northeast China, to compare soil carbon （C） and nitrogen （N） transformations in the two forests. The soil type is Umbri-Gelic Cambosols in Chinese Soil Taxonomy. Soil samples were incubated aerobically at 20℃ and field capacity of 700 g kg^-1 over a period of 27 weeks. The amount of soil microbial biomass and net N mineralization were higher in the Ermans birch than the dark coniferous forest （P 〈 0.05）, whereas the cumulative C mineralization （as CO2 emission） in the dark coniferous forest exceeded that in the Ermans birch （P 〈 0.05）. Release of the cumulative dissolved organic C and dissolved organic N were greater in the Ermans birch than the dark coniferous forest （P 〈 0.05）. The results suggested that differences of forest types could result in considerable change in soil C and N transformations.

关键词： dissolved organic C dissolved organic N Ermans birch-dark coniferous forest soil C transformation soil N transformation

Contribution of Root Respiration to Total Soil Respiration in a Betula ermanii-Dark Coniferous Forest Ecotone of the Changbai Mountains, China

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Pedosphere 2005年第4期15卷 448-455页

作者： LIU Ying han shi-jie ZHOU Yu-Mei ZhanG Jun-Hui Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China）.

Total and root-severed soil respiration rates for five plots set up 50 m apart in a Betula ermanii Cham.-dark coniferous forest ecotone on a north-facing slope of the Changbai Mountains, China, were measured to evaluate the seasonal variations of soil respiration, to assess the effect of soil temperature and water content on soil respiration, and to estimate the relative contributions of root respiration to the total soil respiration. PVC cylinders in each of 5 forest types of a B. ermanii-dark coniferous forest ecotone were used to measure soil respirations both inside and outside of the cylinders. The contribution of roots to the total soil respiration rates ranged from 12.5% to 54.6%. The mean contribution of roots for the different plots varied with the season, increasing from 32.5% on June 26 to 36.6% on August 3 and to 41.8% on October 14. In addition, there existed a significant (P ship between total soil respiration rate and soil temperature at 5 cm soil depth. Also, a similar trend was observed for the soil respiration and soil water content at the surface (0-5 cm) during the same period of time.

关键词： Betula ermanii Cham. dark coniferous forest ecotone root respiration soil respiration

Microbial Activity in a Temperate Forest Soil as Affected by Elevated Atmospheric CO_2

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Pedosphere 2010年第4期20卷 427-435页

作者： ZHENG Jun-Qiang han shi-jie ZHOU Yu-Mei REN Fei-Rong XIN Li-Hua ZhanG Yan Forestry Center Institute of Applied Ecology Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 （China）

Microorganisms play a key role in the response of soil ecosystems to the rising atmospheric carbon dioxide （CO2） as they mineralize organic matter and drive nutrient cycling. To assess the effects of elevated CO2 on soil microbial C and N immobilization and on soil enzyme activities, in years 8 （2006） and 9 （2007） of an open-top chamber experiment that begun in spring of 1999, soil was sampled in summer, and microbial biomass and enzyme activity related to the carbon （C）, nitrogen （N） and phosphorus （P） cycling were measured. Although no effects on microbial biomass C were detected, changes in microbial biomass N and metabolic activity involving C, N and P were observed under elevated CO2. Invertase and .dehydrogenase activities were significantly enhanced by different degrees of elevated CO2. Nitrifying enzyme activity was significantly （P 〈 0.01） increased in the August 2006 samples that received the elevated COs treatment, as compared to the samples that received the ambient treatment. Denitrifying enzyme activity was significantly （P 〈 0.04） decreased by elevated COs treatments in the August 2006 and June 2007 （P 〈 0.09） samples, β-N-acetylglucosaminidase activity was increased under elevated CO2 by 7% and 25% in June and August 2006, respectively, compared to those under ambient CO2. The results of June 2006 samples showed that acid phosphatase activity was significantly enhanced under elevated CO2. Overall, these results suggested that elevated CO2 might cause changes in the belowground C, N and P cycling in temperate forest soils.

关键词： CO2 enrichment microbial biomass soil carbon cycling soil nitrogen cycling

Relationship between diversity of forest plant and community dynamics in eastern mountain area of Heilongjiang Province, China

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Journal of Forestry Research 2006年第4期17卷 289-292页

作者： WANG Qing-gui XING Ya-juan ZHOU Xiao-feng han shi-jie Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 P.R. China Heilongjiang University Harbin 150080 P.R. China Northeast Forestry University Harbin 150040 P.R. China

The biodiversity was studied in 26 communities with different structures in Maoershan National Park and Liangshui Natural Reserve of Northeast Forestry University in Heilongjiang Province, China. Composition index （CI） was taken as a parameter to quantify the community dynamics, which can nicely describe forest community dynamics, meanwhile, the relationship between diversity and community dynamics were also investigated and analyzed. Results showed that the total number species of community, richness, evenness, and Shannon-Wiener diversity index were obviously different in every community. The richness decreased with the increasing CI of every community, which means richness was in inverse proportion to community dynamics. The Shannon-Wiener index of every community increased from the initial stage to the middle stage of succession, and then decreased in the climax stage. The coverage weighted foliage-height diversity index increased along with the increase of CI, which was similar as the oattem diversity.

关键词： Eastern mountain area of Heilongjiang province Shannon-wiener diversity Pattern diversity Community dynamics

大气CO_2浓度非均匀动态分布条件下的气候模拟

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地球物理学报 2012年第9期55卷 2809-2825页

作者：杨成荫王汉杰韩士杰赵苏璇解放军理工大学气象学院南京211101 空军哈尔滨飞行学院哈尔滨150001 中国科学院东亚区域气候-环境重点实验室北京100029 中国科学院沈阳应用生态研究所沈阳110016 南京军区空军气象中心南京210018

利用现有大气本底站的大气CO2浓度观测信息,综合考虑不同经济区划与土地覆盖类型对应的CO2浓度差异及其季节变化规律,构建模式区域内以月为单位的网格化大气CO2浓度非均匀动态分布数据模型.由此数据模型驱动RegCM4-CLM3.5区域气候模式运... 详细信息

利用现有大气本底站的大气CO2浓度观测信息,综合考虑不同经济区划与土地覆盖类型对应的CO2浓度差异及其季节变化规律,构建模式区域内以月为单位的网格化大气CO2浓度非均匀动态分布数据模型.由此数据模型驱动RegCM4-CLM3.5区域气候模式运行,对东亚区2000年3月—2009年2月之间的气候变化特征进行了模拟,进而对大气CO2浓度非均匀动态分布可能引起的区域气候效应进行了初步研究.结果表明:目前气候模式中CO2浓度的常态均匀分布假设可能将温室效应夸大了10%左右.对大气CO2浓度非均匀动态分布影响气温变化的可能机制进行研究表明:CO2的自身效应(改变大气透射率)并不是导致Exp2试验温度降低的主要原因.大气CO2浓度的变化影响了大气与植物胞间CO2分压差,陆地植被通过改变气孔阻力适应这种变化,气孔阻力的变化直接影响到植物与大气间水分的交换,这种作用一方面通过蒸发冷却改变环境温度,另一方面,蒸发水分改变了近地面层湿度,进而水汽扩散到空中影响低云的分布.冬季,植物处于非生长季,对大气CO2浓度变化响应微弱,湿度和低云变化不明显;夏季,植物生长旺盛,由CO2生理学强迫激发的云反馈效应强烈,其效果是使中低云趋于增加,进而减弱了到达对流层低层的太阳短波辐射,造成温室效应减弱.

关键词：大气CO2浓度非均匀动态分布温室效应云反馈 CO2生理学强迫

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氮沉降对森林生态系统土壤碳库的影响

生态学杂志 2007年第10期26卷 1622-1627页

作者：邓小文韩士杰中国科学院沈阳应用生态研究所

森林土壤碳库是陆地生态系统碳库的重要组成部分,对维持全球碳平衡具有重要意义。不断加剧的全球氮沉降有可能改变森林生态系统中碳元素的地球化学循环过程,从而引起森林土壤碳储量的变化。本文从森林土壤碳收支的角度,将氮沉降对森林... 详细信息

森林土壤碳库是陆地生态系统碳库的重要组成部分,对维持全球碳平衡具有重要意义。不断加剧的全球氮沉降有可能改变森林生态系统中碳元素的地球化学循环过程,从而引起森林土壤碳储量的变化。本文从森林土壤碳收支的角度,将氮沉降对森林生态系统土壤碳库影响的复杂过程划分为凋落物分解、细根周转、土壤呼吸和土壤可溶性有机碳淋失4个相对独立的过程。综合国内外研究现状,对其进行了简要评述,指出了目前研究的不足,并探讨了这一研究领域的发展方向。

关键词：氮沉降森林土壤碳库碳收支分解速度碳循环

Synthesis and Crystal Structure of Ferrocenesulfonyl Benzimidazole Derivatives

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有机化学 2003年第Z1期23卷 291-291页

作者： WANG Lu-Yao han jie shi Zhen Department of Chemistry Northwest University Xi''an 710069 Department of Chemistry Northwest University Xi''an 710069 Department of Chemistry Northwest University Xi''an 710069

　　Ferrocene derivatives have attracted much attention over the past two decades in many fields due to their diversebiological activities. [1,2] As a part of a continuing investigation into these compounds, we report here six novel com pounds and the crystal structure of 2a. The synthetic routes of the novel compounds are shown in Scheme 1.……

关键词： crystal structure

Responses of soil microorganisms to elevated CO2 in experiment sites of Pinus sylvestriformis and Pinus koraiensis

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Journal of Forestry Research 2005年第3期16卷 219-222页

作者： JIA Xia han shi-jie ZHOU Yu-mei Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 P. R. China College of Earth Seience and Land Resottrces Management Chang＇an University Xi＇an 710064 P R. China Gradnate Academy of the Chinese Academy of Sciences Beijing 100039 P R. China

Responses of soil microbial activities to elevated CO, in experiment sites of Pinus sylvestriformis and Pinus koratensts seecllmgs were studied in summer in 2003. The results indicated the number of bacteria decreased significantly （p 〈 0.05） under elevated CO, for Pinus syivestriformis and Pinups koraiensis. Amylase and invertase activities in soil increased for Pinus syivestriformis and decreased for Pinus koraiensis with CO2 enrichment compared with those at ambient （350 pmol·mol^-1）. The size of microbial biomass C also decreased significantly at 700 μmol- mol^-1 CO2. Bacterial community structure had some evident changes under elevated CO, by DGGE （Denaturing Gradient Gel Electrophoresis） analysis of bacterial 16S rDNA gene fragments amplified by PCR from DNA extracted directly from soil. The results suggested that responses of soil microorganisms to elevated CO2 would be related to plant species exposed to elevated CO2.

关键词： Bacterial community Bacterial numbers Elevated CO2 Soil enzyme activity.