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Journal of Integrative Plant Biology 2006年第4期48卷 409-414页

作者： Wei Wang Ji-Xun Guo Jiang Feng Takehisa Oikawa Department of Ecology College of Environmental Sciences Peking University Beijing 100871 China Key Laboratory for Vegetation Ecology of the Ministry of Education Northeast Normal University Changchun 130024 China Institutes of Biological Sciences University of Tsukuba Tsukuba Ibaraki 305-8572 Japan

The loss of carbon through root respiration Is an Important component of grassland carbon budgets. However, few data are available concerning the contribution of root respiration to total soil respiration in grasslands in China. We Investigated seasonal variations of soil respiration rate, root blomaaa, microbial blomaaa C and organic C content of the soil In a semi-arid Leymus chinensis （Trin.） Tzvel. grassland of northeast China during the 2002 growing season （from May to September）. The linear regression relationship between soil respiration rate and root blomaaa was used to determine the contribution of root respiration to total soil respiration. Soil respiration rate ranged from 2.5 to 11.9 g C/m^2 per d with the maximum in late June and minimum In September. The microbial blomaaa C and organic C content of the soil ranged from 0.3 to 1.5 g C/m^2 and from 29 to 34 g C/kg respectively. root blomaaa had two peaks, In early June （1.80 kg/m^2） and mid-August （1.73 kg/m^2）. root respiration rate peaked In mid-August （6.26 g C/m^2 per d）, whereas microbial respiration rate peaked In late June （7.43 g C/m^2 per d）. We estimated that the contribution of root respiration to total soil respiration during the growing season ranged from 38% to 76%.

关键词： meadow steppe root biomass root respiration soil organic carbon soil respiration.

Contribution of root respiration to total soil respiration during non-growing season in mine reclaimed soil with different covering-soil thicknesses

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International Journal of Coal Science & Technology 2021年第5期8卷 1130-1137页

作者： Min Chen Xiaoyang Chen Zhiyong Hu Tingyu Fan Shiwen Zhang Ying Liu State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines(Anhui University of Science and Technology) Huainan 232001AnhuiChina School of Earth and Environment Anhui University of Science and TechnologyHuainan 232001AnhuiChina Anhui Engineering Laboratory for Comprehensive Utilization of Water and Soil Resources&Ecological Protection in Mining Area with High Groundwater Level Huainan 232001AnhuiChina

An accurate assessment of root respiration in mine reclaimed soil is important for effectively evaluating mining area *** study investigated dynamic changes in root respiration and the contribution of root respiration to total soil respiration(R_(r)/R_(t) ratio)during the non-growing season in mine reclaimed soil,with different covering-soil *** to the covering-soil thicknesses,the study area was divided into four sites:10-25 cm(site A),25-45 cm(site B),45-55 cm(site C),and 55-65 cm(site D).From November 2017 to April 2018(except February in 2018),the soil respiration,root respiration,temperature at 5 cm,water content,and root biomass were *** results show that soil temperature and root respiration exhibited similar diurnal and monthly *** root respiration is strongly influenced by soil temperature during the non-growing season,with an exponential and positive relationship(Proot respiration varies with the covering-soil thickness and is greatest with a covering-soil thickness of 25-45 *** R_(r)/R_(t) ratio also exhibits monthly *** the non-growing season,the mean value of the R_(r)/R_(t) ratio is 51.15%in mine reclaimed *** study indicates that root respiration is the primary source of soil respiration and is an important factor for estimating the potential emission of soil CO_(2) from mine reclaimed soil at the regional scale.

关键词： root respiration Soil respiration Soil temperature Soil water content root biomass

Adjustment of Forest Ecosystem root respiration as Temperature Warms

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Journal of Integrative Plant Biology 2008年第11期50卷 1467-1483页

作者： Andrew J.Burton Jerry M.Melillo Serita D.Frey Ecosystem Science Center Michigan Technological University School of Forest Resources and Environmental Science Michigan Technological University The Ecosystems Center Marine Biological Laboratory Department of Natural Resources University of New Hampshire

Adjustment of ecosystem root respiration to warmer climatic conditions can alter the autotrophic portion of soil respiration and influence the amount of carbon available for biomass production. We examined 44 published values of annual forest root respiration and found an increase in ecosystem root respiration with increasing mean annual temperature （MAT）, but the rate of this cross-ecosystem increase （Q10 = 1.6） is less than published values for short-term responses of root respiration to temperature within ecosystems （Q10 = 2-3）. When specific root respiration rates and root biomass values were examined, there was a clear trend for decreasing root metabolic capacity （respiration rate at a standard temperature） with increasing MAT. There also were tradeoffs between root metabolic capacity and root system biomass, such that there were no instances of high growing season respiration rates and high root biomass occurring together. We also examined specific root respiration rates at three soil warming experiments at Harvard Forest, USA, and found decreases in metabolic capacity for roots from the heated plots. This decline could be due to either physiological acclimation or to the effects of co-occurring drier soils on the measurement date. Regardless of the cause, these findings clearly suggest that modeling efforts that allow root respiration to increase exponentially with temperature, with Q10 values of 2 or more, may over-predict root contributions to ecosystem CO2 efflux for future climates and underestimate the amount of C available for other uses, including net primary productivity.

关键词： acclimation climatic warming root biomass root respiration soil warming.

Variations of root and heterotrophic respiration along environmental gradients in China’s forests

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Journal of Plant Ecology 2013年第5期6卷 358-367页

作者： Pin Li Yuanhe Yang Jingyun Fang Department of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Aims root and heterotrophic respiration may respond differently to environmental variability,but little evidence is available from largescale *** we aimed to examine variations of root and heterotrophic respiration across broad geographic,climatic,soil and biotic *** We conducted a synthesis of 59 field measurements on root and heterotrophic respiration across China’s *** Findings root and heterotrophic respiration varied differently with forest types,of which evergreen broadleaf forest was significantly different from those in other forest types on heterotrophic respiration but without statistically significant differences on root *** results also indicated that root and heterotrophic respiration exhibited similar trends along gradients of precipitation,soil organic carbon and satellite-indicated vegetation ***,they exhibited different relationships with temperature:root respiration exhibited bimodal patterns along the temperature gradient,while heterotrophic respiration increased monotonically with ***,they showed different relationships with MOD17 GPP,with increasing trend observed for root respiration whereas insignificant change for heterotrophic *** addition,root and heterotrophic respiration exhibited different changes along the age sequence,with insignificant change for root respiration and decreasing trend for heterotrophic ***,these results suggest that root and heterotrophic respiration may respond differently to environmental *** findings could advance our understanding on the different environmental controls of root and heterotrophic respiration and also improve our ability to predict soil CO_(2) flux under a changing environment.

关键词： enhanced vegetation index forest age heterotrophic respiration latitude mean annual temperature mean annual precipitation root respiration GPP

Intensive management enhances mycorrhizal respiration but decreases free-living microbial respiration by affecting microbial abundance and community structure in Moso bamboo forest soils

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Pedosphere 2024年第2期34卷 508-519页

作者： Wenhao JIN Jiangfei GE Shuai SHAO Liyuan PENG Jiajia XING Chenfei LIANG Junhui CHEN Qiufang XU Hua QIN State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China School of Environmental and Resource Sciences Zhejiang A&F UniversityHangzhou 311300China

Intensive management is known to markedly alter soil carbon(C)storage and turnover in Moso bamboo forests compared with extensive ***,the effects of intensive management on soil respiration(RS)components remain *** study aimed to evaluate the changes in different RScomponents(root,mycorrhizal,and free-living microorganism respiration)in Moso bamboo forests under extensive and intensive management practices.A1-year in-situ microcosm experiment was conducted to quantify the RScomponents in Moso bamboo forests under the two management practices using mesh screens of varying *** results showed that the total RSand its components exhibited similar seasonal variability between the two management *** with extensive management,intensive management significantly increased cumulative respiration from mycorrhizal fungi by 36.73%,while decreased cumulative respiration from free-living soil microorganisms by 8.97%.Moreover,the abundance of arbuscular mycorrhizal fungi(AMF)increased by 43.38%,but bacterial and fungal abundances decreased by 21.65%and 33.30%,respectively,under intensive *** management practices significantly changed the bacterial community composition,which could be mainly explained by soil pH and available *** fungi and intensive management affected the interrelationships between bacterial *** equation modeling indicated that intensive management changed the cumulative RSby elevating AMF abundance and lowering bacterial *** concluded that intensive management reduced the microbial respiration-derived C loss,but increased mycorrhizal respiration-derived C loss.

关键词： arbuscular mycorrhizal fungi extensive management microbial co-occurrence network root respiration soil organic C soil respiration structural equation model

Three-source partitioning of soil respiration by ^(13)C natural abundance and its variation with soil depth in a plantation

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Journal of Forestry Research 2016年第3期27卷 533-540页

作者： Wenchen Song Xiaojuan Tong Jinsong Zhang Ping Meng College of Forestry Beijing Forestry University Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration Research Institute of ForestryChinese Academy of Forestry

Partitioning soil respiration into three components is vital to identify CO_2 sink or source and can help us better understand soil carbon dynamics. However, knowledge about the influences of soil depth and the priming effect on soil respiration components under field has been limited. Three components of soil respiration（root respiration, rhizomicrobial respiration and basal respiration） in a plantation in the hilly area of the North China were separated by the 13 C natural abundance method. The results showed that the average proportions of rhizomicrobial respiration, root respiration and basal respiration at the 25-65 cm depths were about 14, 23 and 63 %, respectively. Three components of soil respiration varied with soil depth, and root respiration was the main component of soil respiration in deeper soil. The priming effect was obvious for the deep soil respiration, especially at the 40-50 cm depth. Thus, depth and priming effect should be taken into account to increase the accuracy of estimations of soil carbon flux.

关键词： Soil respirationRhizomicrobial respiration abundance Soil depth Rhizosphere respiration root respiration 13C natural

Advances on the Responses of root Dynamics to Increased Atmospheric CO_(2) and Global Climate Change

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Agricultural Sciences in China 2006年第3期5卷 161-168页

作者： ZHOU Zheng-chao SHANGGUAN Zhou-ping State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling 712100 P.R.China Northwest A ＆ F University Yangling 712100 P.R.China

Plant roots dynamics responses to elevated atmospheric CO2 concentration, increased temperature and changed precipitation can be a key link between plant growth and long-term changes in soil organic matter and ecosystem carbon balance. This paper reviews some experiments and hypotheses developed in this area, which mainly include plant fine roots growth, root turnover, root respiration and other root dynamics responses to elevated CO2 and global climate change. Some recent new methods of studying root systems were also discussed and summarized. It holds herein that the assemblage of information about root turnover patterns, root respiration and other dynamic responses to elevated atmospheric CO2 and global climatic change can help to better understand and explore some new research areas. In this paper, some research challenges in the plant root responses to the elevated CO2 and other environmental factors during global climate change were also demonstrated.

关键词： elevated CO2 temperature precipitation root turnover root respiration minirhizotrons isotope trace