Title: A cross-biome synthesis of soil respiration and its determinants under simulated precipitation changes

Abstract

Soil respiration (R_s) is the second-largest terrestrial carbon (C) flux. Although R_s has been extensively studied across a broad range of biomes, there is surprisingly little consensus on how the spatiotemporal patterns of Rs will be altered in a warming climate with changing precipitation regimes. Here, we present a global synthesis Rs data from studies that have manipulated precipitation in the field by collating studies from 113 increased precipitation treatments, 91 decreased precipitation treatments, and 14 prolonged drought treatments. Our meta-analysis indicated that when the increased precipitation treatments were normalized to 28% above the ambient level, the soil moisture, R_s,and the temperature sensitivity (Q₁₀) values increased by an average of 17%, 16%, and 6%, respectively, and the soil temperature decreased by -1.3%. The greatest increases in R_s and Q₁₀ were observed in arid areas, and the stimulation rates decreased with increases in climate humidity. When the decreased precipitation treatments were normalized to 28% below the ambient level, the soil moisture and Rs values decreased by an average of -14% and -17%, respectively, and the soil temperature and Q₁₀ values were not altered. The reductions in soil moisture tended to be greater in more humid areas. Prolonged drought without alterations inmore » the amount of precipitation reduced the soil moisture and Rs by -12% and -6%, respectively, but did not alter Q₁₀. Overall, our synthesis suggests that soil moisture and Rs tend to be more sensitive to increased precipitation in more arid areas and more responsive to decreased precipitation in more humid areas. The responses of R_s and Q₁₀ were predominantly driven by precipitation-induced changes in the soil moisture, whereas changes in the soil temperature had limited impacts. Finally, our synthesis of prolonged drought experiments also emphasizes the importance of the timing and frequency of precipitation events on ecosystem C cycles. Given these findings, we urge future studies to focus on manipulating the frequency, intensity, and seasonality of precipitation with an aim to improving our ability to predict and model feedback between R_s and climate change.« less

Authors:

Liu, Lingli ^[1]; Wang, Xin ^[2]; Lajeunesse, Marc J. ^[3]; Miao, Guofang ^[4]; Piao, Shilong ^[5]; Wan, Shiqiang ^[6]; Wu, Yuxin ^[7]; Wang, Zhenhua ^[2]; Yang, Sen ^[2]; Li, Ping ^[2]; Deng, Meifeng ^[2]

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+ Show Author Affiliations

1. Chinese Academy of Sciences (CAS), Beijing (China). State Key Lab. of Vegetation and Environmental Change, Inst. of Botany
2. Chinese Academy of Sciences (CAS), Beijing (China). State Key Lab. of Vegetation and Environmental Change, Inst. of Botany; Univ. of Chinese Academy of Sciences, Yuquanlu, Beijing (China)
3. Univ. of South Florida, Tampa, FL (United States). Dept. of Integrative Biology
4. North Carolina State Univ., Raleigh, NC (United States). Dept. of Forestry and Environmental Resources
5. Peking Univ., Beijing (China). Dept. of Ecology, College of Urban and Environmental Science
6. Henan Univ., Kaifeng, Henan (China). State Key Lab. of Cotton Biology, Key Lab. of Plant Stress Biology,College of Life Sciences
7. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Division

Publication Date:

Wed Nov 11 00:00:00 EST 2015

Research Org.:

Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

Sponsoring Org.:

USDOE Office of Science (SC)

OSTI Identifier:

1474928

Grant/Contract Number:  

AC02-05CH11231

Resource Type:

Accepted Manuscript

Journal Name:

Global Change Biology

Additional Journal Information:

Journal Volume: 22; Journal Issue: 4; Journal ID: ISSN 1354-1013

Publisher:

Wiley

Country of Publication:

United States

Language:

English

Subject:

54 ENVIRONMENTAL SCIENCES; apparent Q10; aridity index; drought; meta‐analysis; precipitation regime; soil moisture; soil temperature; wet