Changes of carbon stocks in alpine grassland soils from 2002 to 2011 on the Tibetan Plateau and their climatic causes

• Published in: Geoderma
• Main Authors: Chen, Litong, Jing, Xin, Flynn, Dan F. B., Shi, Yue, Kuehn, Peter, Scholten, Thomas, He, Jin-Sheng
• Other Authors: Chen, LT (reprint author), Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China., Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China., Peking Univ, Coll Urban & Environm Sci, Dept Ecol, Beijing 100871, Peoples R China., Peking Univ, Key Lab Earth Surface Proc, Minist Educ, Beijing 100871, Peoples R China., Arnold Arboretum Harvard Univ, 1300 Ctr St, Boston, MA USA., Chinese Acad Sci, Inst Bot, State Key Lab Vegetat Environm Change, Beijing 100093, Peoples R China., Univ Tubingen, Dept Geosci Soil Sci & Geomorphol, D-72079 Tubingen, Germany.
• Format: Journal/Newspaper
• Language: English
• Published: GEODERMA 2017
• Subjects: Soil organic carbon (SOC); SOC stocks; Repeated soil inventory; Alpine meadow; Alpine steppe; Tibetan Plateau; NET PRIMARY PRODUCTIVITY; ORGANIC-CARBON; TERRESTRIAL ECOSYSTEMS; RECENT DECADES; ARCTIC TUNDRA; FOREST SOILS; GREEN-UP; NITROGEN; CHINA; DYNAMICS; Arctic; Climate change; Tundra
• Online Access: https://hdl.handle.net/20.500.11897/475143; https://doi.org/10.1016/j.geoderma.2016.11.016

Based on field observations, remote sensing, and modeling, recent studies have reported inconsistent changes in soil organic carbon (SOC) stocks in grasslands of the Tibetan Plateau over the past few decades. However, direct evidence about the changes in SOC stocks in the plateau's grasslands coming from in situ, site-by-site, repeated surveys is rare. In this study, we carried out a repeated soil sampling to assess the changes in SOC stocks in the alpine grasslands across the Tibetan Plateau. Across all 41 sites in the alpine grasslands, SOC stocks exhibited a significant increase from 2002 to 2011 at an overall rate of 4.66 g Cm-2 yr(-1). Mesic and low-temperature-limited alpine meadows showed an average carbon gain of 25.8 g Cm-2 yr(-1), whereas the relatively dry alpine steppes exhibited a slight carbon loss of 11.9 g Cm-2 yr(-1). Spatially, the changes in SOC stocks were significantly related to the original SOC stocks across alpine steppes, and soils with low carbon tended to gain carbon. Moreover, the changes in SOC stocks were also associated with March-April precipitation in alpine meadows, and with mean annual precipitation (MAP) in alpine steppes, with drier sites generally gaining carbon. Overall, the alpine grasslands of the Tibetan Plateau significantly accumulated SOC over this 10-year period, but many more site surveys are needed to comprehensively access the changes in SOC stocks across alpine grasslands on the plateau; and management strategies enhancing the ability of C sequestration should differ between alpine meadows and steppes due to their contrasting climate conditions. (C) 2016 Elsevier B.V. All rights reserved. Strategic Priority Research Program - "Climate Change: Carbon Budget and Relevant Issues" of the Chinese Academy of Sciences [XDA05050404]; National Natural Science Foundation of China [31570481]; National Basic Research Program of China [2014CB954004] SCI(E) ARTICLE 166-174 288