Effects of carbon turnover time on terrestrial ecosystem carbon storage
Yaner Yan1,2,Xuhui Zhou2,3,Lifeng Jiang4,and Yiqi Luo4,5,6Yaner Yan et al. Yaner Yan1,2,Xuhui Zhou2,3,Lifeng Jiang4,and Yiqi Luo4,5,6
1Key Laboratory for Eco-Agricultural Biotechnology around Hongze
Lake/Collaborative Innovation Center of Regional Modern Agriculture &
Environmental Protection, Huaiyin Normal University, Huai'an 223300, China
2Tiantong National Station for Forest Ecosystem Research, Shanghai Key
Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological
and Environmental Sciences, East China Normal University, Shanghai 200062,
China
3Center for Global Change and Ecological forecasting, East China Normal
University, Shanghai 200062, China
4Center for Ecosystem Science and Society, Northern Arizona University,
Arizona, 86011, USA
5Department of Microbiology and Plant Biology, University of Oklahoma,
OK, USA
6Center for Earth System Science, Tsinghua University, Beijing, China
1Key Laboratory for Eco-Agricultural Biotechnology around Hongze
Lake/Collaborative Innovation Center of Regional Modern Agriculture &
Environmental Protection, Huaiyin Normal University, Huai'an 223300, China
2Tiantong National Station for Forest Ecosystem Research, Shanghai Key
Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological
and Environmental Sciences, East China Normal University, Shanghai 200062,
China
3Center for Global Change and Ecological forecasting, East China Normal
University, Shanghai 200062, China
4Center for Ecosystem Science and Society, Northern Arizona University,
Arizona, 86011, USA
5Department of Microbiology and Plant Biology, University of Oklahoma,
OK, USA
6Center for Earth System Science, Tsinghua University, Beijing, China
Received: 11 May 2017 – Discussion started: 29 May 2017 – Revised: 12 Oct 2017 – Accepted: 25 Oct 2017 – Published: 04 Dec 2017
Abstract. Carbon (C) turnover time is a key factor in determining C storage capacity in various plant and soil pools as well as terrestrial C sink in a changing climate. However, the effects of C turnover time on ecosystem C storage have not been well explored. In this study, we compared mean C turnover times (MTTs) of ecosystem and soil, examined their variability to climate, and then quantified the spatial variation in ecosystem C storage over time from changes in C turnover time and/or net primary production (NPP). Our results showed that mean ecosystem MTT based on gross primary production (GPP; MTTEC_GPP = Cpool/GPP, 25.0 ± 2.7 years) was shorter than soil MTT (MTTsoil = Csoil/NPP, 35.5 ± 1.2 years) and NPP-based ecosystem MTT (MTTEC_NPP = Cpool/NPP, 50.8 ± 3 years; Cpool and Csoil referred to ecosystem or soil C storage, respectively). On the biome scale, temperature is the best predictor for MTTEC (R2 = 0.77, p < 0.001) and MTTsoil (R2 = 0.68, p < 0.001), while the inclusion of precipitation in the model did not improve the performance of MTTEC (R2 = 0.76, p < 0.001). Ecosystem MTT decreased by approximately 4 years from 1901 to 2011 when only temperature was considered, resulting in a large C release from terrestrial ecosystems. The resultant terrestrial C release caused by the decrease in MTT only accounted for about 13.5 % of that due to the change in NPP uptake (159.3 ± 1.45 vs. 1215.4 ± 11.0 Pg C). However, the larger uncertainties in the spatial variation of MTT than temporal changes could lead to a greater impact on ecosystem C storage, which deserves further study in the future.
The effects of C turnover time on ecosystem C storage have not been well explored, so we quantified the spatial variation in ecosystem C storage over time from changes in C turnover time and/or NPP. Our results showed that the terrestrial C release caused by the decrease in MTT only accounted for about 13.5 % of that due to the change in NPP uptake. However, the larger uncertainties in the spatial variation of MTT than temporal changes would lead to a greater impact on ecosystem C storage.
The effects of C turnover time on ecosystem C storage have not been well explored, so we...
