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Science China Earth Sciences 2023年第5期66卷 1072-1086页

作者： Guocheng WANG Liujun XIAO Ziqi LIN Qing ZHANG Xiaowei GUO Annette COWIE Shuai ZHANG Mingming WANG Songchao CHEN Ganlin ZHANG Zhou SHI Wenjuan SUN Zhongkui LUO Institute of Agriculture Remote Sensing and Information Technology College of Environmental and Resource SciencesZhejiang UniversityHangzhou310058China LAPC Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing100029China School of Atmospheric Sciences Guangdong Province Key Laboratory for Climate Change and Natural Disaster StudiesSun Yat-sen UniversityZhuhai519082China New South Wales Department of Primary Industries University of New EnglandArmidaleNSW2351Australia State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing210008China Academy of Ecological Civilization Zhejiang UniversityHangzhou310058China Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationZhejiang UniversityHangzhou310058China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China Key Laboratory of Agricultural Remote Sensing and Information System Zhejiang ProvinceHangzhou310058China

Plant root-derived carbon(C)inputs(I_(root))are the primary source of C in mineral bulk ***,a fraction of I_(root)may lose quickly(I_(loss),e.g.,via rhizosphere microbial respiration,leaching and fauna feeding)without contributing to long-term bulk soil C storage,yet this loss has never been quantified,particularly on a global *** this study we integrated three observational global data sets including soil radiocarbon content,allocation of photo synthetically assimilated C,and root biomass distribution in 2,034 soil profiles to quantify I_(root)and its contribution to the bulk soil C *** show that global average I_(root)in the 0-200 cm soil profile is 3.5 Mg ha^(-1)yr^(-1),~80%of which(i.e.,I_(loss))is lost rather than co ntributing to long-term bulk soil C storage.I_(root)decreases exponentially with soil depth,and the top 20 cm soil contains>60%of total I_(root).Actual C input contributing to long-term bulk soil storage(i.e.,I_(root)-I_(loss))shows a similar depth distribution to I_(root).We also map I_(loss)and its depth distribution across the *** results demonstrate the global significance of direct C losses which limit the contribution of I_(root)to bulk soil C storage;and provide spatially explicit data to facilitate reliable soil C predictions via separating direct C losses from total root-derived C inputs.

关键词： Carbon inputs root biomass Soil organic carbon Depth distribution Bulk soil carbon Radiocarbon

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.

Contribution of root Respiration to Total Soil Respiration in a Leymus chinensis （Trin.） Tzvel, Grassland of Northeast China

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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.

Fine root morphology and soil properties under influence of different tree stands along an altitudinal climosequence in the Carpathian mountains

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Forest Ecosystems 2022年第5期9卷 692-700页

作者： Karolina Staszel Ewa Błonska Jarosław Lasota Department of Ecology and Silviculture Faculty of ForestryUniversity of Agriculture in Krakow29 Listopada 46 Str31-425KrakowPoland

In an era of climate change, understanding the factors that impact root systems can improve our understanding of carbon cycling in forest ecosystems. The study objective was to determine the impact of climatic conditions on the biomass and morphology of roots of different tree species along an elevation gradient, and consequently on properties of montane forest soils. The study plots were established at three different elevations(600, 800 and1000 m a.s.l.) along a slope with an inclination of 15°. The research plots were located in a beech stand(Fagus sylvatica L.) and fir stand(Abies alba Mill.). Soil samples were collected from each study plot, for which basic physical and chemical properties were determined. Additionally, we determined the morphology, production and decomposition rate of fine roots. Our analyses confirmed the significance of climatic conditions in the formation of soil properties, in particular the amount of accumulated carbon and nitrogen content. A decrease of root biomass and reduced root growth were recorded with increasing elevation. The characteristics of roots were linked with the properties of the studied mountain soils, in particular p H, alkaline cation content and content of selected micronutrients. Limitation of root growth in higher elevations affected both study species. Additional research into the formation of tree root morphology is needed, especially in mountainous regions where changes may occur more dynamically. This will provide a better understanding of how stands can cope with different types of environmental stress.

关键词： Beech Fir Forest ecosystem root biomass Soil properties

Effect of nitrogen addition, form and clipping on competitive interactions between grassland species

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Journal of Plant Ecology 2014年第3期7卷 222-230页

作者： Carly J.Stevens David J.G.Gowing Lancaster Environment Centre Lancaster UniversityLancasterLA14YQUK Department of Earth Environment and EcosystemsThe Open UniversityWalton HallMilton KeynesMK76AAUK

Aims Although the effects of N addition on plant biomass are well understood,we know a lot less about the importance of N form even though some studies have shown different impacts from reduced and oxidized forms of ***,responses to grazing are likely to interact with the response to N *** experiment investigates the interactive effects of N addition and form with clipping on competition between three grassland *** The three species(Anthoxanthum odoratum L.,Plantago lanceolata *** Prunella vulgaris L.)were grown alone and in combination with factorial additions of deionized water,sodium nitrate and ammonium chloride,and a clipping ***-and belowground biomass was harvested after 4 *** Findings In monocultures,the results show increases in biomass with N addition,but clipping resulted in fewer changes with species displaying varying degrees of growth *** was the strongest competitor when grown with other *** monocultures without clipping,N form was not important,but in the presence of clipping and in different species combinations,N form became *** two-and three-way interactive effects were observed showing that complex interactions exist between N addition,clipping and species *** results have important implications when considering the effects of N deposition.

关键词： aboveground biomass ammonium grazing nitrate root biomass

Effects of plant roots on soil preferential pathways and soil matrix in forest ecosystems

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Journal of Forestry Research 2015年第2期26卷 397-404页

作者： Yinghu Zhang Jianzhi Niu Weili Zhu Xiaoqing Du Jiao Li Key Laboratory Soil and Water Conservation and Desertification Combating Ministry of EducationCollege of Soil and Water ConservationBeijing Forestry University

To characterize effects of plant roots on preferential flow（PF）,we measured root length density（RLD）and root biomass（RB） in Jiufeng National Forest Park,Beijing,*** were made for RLD and RB between soil preferential pathways and soil *** and RB declined with the increasing soil depth（0–10,10–20,20–30,30–40,40–50,50–60 cm） in all experimental *** was greater in soil preferential pathways than in the surrounding soil matrix and was 69.5,75.0 and72.2 % for plant roots of diameter（d）／1,1 ／ d ／ 3 and3 ／ d ／ 5 mm,*** root systems had the most pivotal influence on soil preferential flow in this forest *** all experimental plots,RB content was the sum of RB from soil preferential pathways and the soil matrix in each soil *** respect to 6 soil depth gradient（0–10,10–20,20–30,30–40,40–50,50–60 cm） in each plot,the number of soil depth gradient that RB content was greater in soil preferential pathways than in the soil matrix was characterized,and the proportion was68.2 % in all plots.

关键词： Preferential flow Preferential pathways Soil matrix root length density root biomass

Effect of repeated spring drought and summer heavy rain on managed grassland biomass production and CO_(2) efflux

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Journal of Plant Ecology 2017年第3期10卷 476-485页

作者： Eva Darenova Petr Holub Lenka Krupkova Marian Pavelka Global Change Research Institute Czech Academy of SciencesBelidla 4aCZ-60300 BrnoCzech Republic

Aims Ecosystem respiration represents an important component of the carbon *** response of respiration to climate change can have a significant effect on carbon sequestration in terrestrial ecosystems in the future when,according to climate scenarios,spring drought and consequent summer heavy rains are *** of our study were to determine the effect of repeated spring drought on biomass production and CO_(2) efflux from a mountain grassland in Beskydy Mountains in the Czech Republic and to evaluate factors driving the differences among the study *** CO_(2) efflux was measured on plots with ambient precipitation con-ditions(AMB)and on plots where drought conditions(DRY)in the first half of the growing seasons and consequent heavy rain were simulated in *** Findings The spring drought significantly decreased the amount of above-ground biomass sampled just after the simulated drought in all years except for *** the contrary,the spring drought stimulated root *** drought also resulted in a rapid decrease in CO_(2) *** was lower by up to 46%for the DRY treatment compared to AMB *** the sim-ulated drought period,differences in CO_(2) efflux between the treatments gradually *** heavy rains in DRY resulted in fast but temporary increase in CO_(2) *** can assume that the future spring drought will have a significant effect on carbon balance of grassland *** impact will depend on the length of the dry period and the time between the beginning of the growing season and the dry period.

关键词： above-ground biomass Beskydy Mountains rainfall manipulation respiration rainout shelters root biomass

Analysis of root fractal characteristics in remote areas of the Taklimakan desert,China

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Forestry Studies in China 2008年第2期10卷 67-73页

作者： YANG Xiao-lin ZHANG Xi-ming LI Yi-ling LI Shao-cai SUN Hai-long Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 R R. China Graduate University of the Chinese Academy of Sciences Beijing 100039 P. R. China Sichuan Lizi Eco-technology Co. Ltd Chengdu 610031 E R. China

Fractal geometry is a potential new approach to analyze the root architecture, which may offer improved ways to quantify and summarize root system complexity as well as yield ecological and physiological insights into the functional relevance of specific architectural patterns. Fractal analysis is a sensitive measure of root branching intensity and fractal dimension expresses the ＂space filling＂ properties of a structure. The objective of this study was to find out the fractal characteristics of root systems in a remote area of the Taklimakan desert in China. The entire root system of two naturally occurring species were excavated and exposed with shov- els in 2007. The species were Tamarix taklamakanensis and Calligonum roborovskii. A one-factorial ANOVA with species as factor showed statistically a highly significant difference in fractal dimensions, indicating differences in their pattern of root branching. There was no relationship between root diameter and two parameters of fractal root models a and q, representing general characteris- tics of root systems, for either species （a： the ratio of the sum of root cross-sectional areas after a branching to the cross-sectional area before root division; q： the distribution of the cross-sectional areas after branching）. We have found significant linear relation- ships between the diameter after branching and root length and biomass respectively, because of the self-similarity of root branching. Branching rules are the same for roots of all sizes and lengths. root biomass for the root systems of entire trees can be estimated by measuring the diameter of each root at the base of the trunk or the diameter after branching. We have shown that the diameter of each root at the base of the trunk and the diameter after branching are effective indices that can be measured easily in order to estimate the root lengths, biomass and other parameters of root architecture.

关键词： Taklimakan desert root architecture fractal dimension root length root biomass