Non-growing-season soil respiration is controlled by freezing and thawing processes in the summer monsoon-dominated Tibetan alpine grassland

NWIPB OpenIR

	Non-growing-season soil respiration is controlled by freezing and thawing processes in the summer monsoon-dominated Tibetan alpine grassland
	Wang, Yonghui ; Liu, Huiying ; Chung, Haegeun ; Yu, Lingfei ; Mi, Zhaorong ; Geng, Yan ; Jing, Xin ; Wang, Shiping ; Zeng, Hui ; Cao, Guangmin ; Zhao, Xinquan ; He, Jin-Sheng
	2014-10-01
发表期刊	GLOBAL BIOGEOCHEMICAL CYCLES ; Wang, YH; Liu, HY; Chung, H; Yu, LF; Mi, ZR; Geng, Y; Jing, X; Wang, SP; Zeng, H; Cao, GM; Zhao, XQ; He, JS.Non-growing-season soil respiration is controlled by freezing and thawing processes in the summer monsoon-dominated Tibetan alpine grassland,GLOBAL BIOGEOCHEMICAL CYCLES,2014,28(10):1081
摘要	The Tibetan alpine grasslands, sharing many features with arctic tundra ecosystems, have a unique non-growing-season climate that is usually dry and without persistent snow cover. Pronounced winter warming recently observed in this ecosystem may significantly alter the non-growing-season carbon cycle processes such as soil respiration (R-s), but detailed measurements to assess the patterns, drivers of, and potential feedbacks on R-s have not been made yet. We conducted a 4 year study on R-s using a unique R-s measuring system, composed of an automated soil CO2 flux sampling system and a custom-made container, to facilitate measurements in this extreme environment. We found that in the nongrowing season, (1) cumulative R-s was 82-89g C m(-2), accounting for 11.8-13.2% of the annual total R-s; (2) surface soil freezing controlled the diurnal pattern of R-s and bulk soil freezing induced lower reference respiration rate (R-0) and temperature sensitivity (Q(10)) than those in the growing season (0.40-0.53 versus 0.84-1.32 mu mol CO2 m(-2)s(-1) for R-0 and 2.5-2.9 versus 2.9-5.6 for Q(10)); and (3) the intraannual variation in cumulative R-s was controlled by accumulated surface soil temperature. We found that in the summer monsoon-dominated Tibetan alpine grassland, surface soil freezing, bulk soil freezing, and accumulated surface soil temperature are the day-, season-, and year-scale drivers of the non-growing-season R-s, respectively. Our results suggest that warmer winters can trigger carbon loss from this ecosystem because of higher Q(10) of thawed than frozen soils.; The Tibetan alpine grasslands, sharing many features with arctic tundra ecosystems, have a unique non-growing-season climate that is usually dry and without persistent snow cover. Pronounced winter warming recently observed in this ecosystem may significantly alter the non-growing-season carbon cycle processes such as soil respiration (R-s), but detailed measurements to assess the patterns, drivers of, and potential feedbacks on R-s have not been made yet. We conducted a 4 year study on R-s using a unique R-s measuring system, composed of an automated soil CO2 flux sampling system and a custom-made container, to facilitate measurements in this extreme environment. We found that in the nongrowing season, (1) cumulative R-s was 82-89g C m(-2), accounting for 11.8-13.2% of the annual total R-s; (2) surface soil freezing controlled the diurnal pattern of R-s and bulk soil freezing induced lower reference respiration rate (R-0) and temperature sensitivity (Q(10)) than those in the growing season (0.40-0.53 versus 0.84-1.32 mu mol CO2 m(-2)s(-1) for R-0 and 2.5-2.9 versus 2.9-5.6 for Q(10)); and (3) the intraannual variation in cumulative R-s was controlled by accumulated surface soil temperature. We found that in the summer monsoon-dominated Tibetan alpine grassland, surface soil freezing, bulk soil freezing, and accumulated surface soil temperature are the day-, season-, and year-scale drivers of the non-growing-season R-s, respectively. Our results suggest that warmer winters can trigger carbon loss from this ecosystem because of higher Q(10) of thawed than frozen soils.
文献类型	期刊论文
条目标识符	http://210.75.249.4/handle/363003/16948
专题	中国科学院西北高原生物研究所
推荐引用方式 GB/T 7714	Wang, Yonghui,Liu, Huiying,Chung, Haegeun,et al. Non-growing-season soil respiration is controlled by freezing and thawing processes in the summer monsoon-dominated Tibetan alpine grassland[J]. GLOBAL BIOGEOCHEMICAL CYCLES, Wang, YH; Liu, HY; Chung, H; Yu, LF; Mi, ZR; Geng, Y; Jing, X; Wang, SP; Zeng, H; Cao, GM; Zhao, XQ; He, JS.Non-growing-season soil respiration is controlled by freezing and thawing processes in the summer monsoon-dominated Tibetan alpine grassland,GLOBAL BIOGEOCHEMICAL CYCLES,2014,28(10):1081,2014.
APA	Wang, Yonghui.,Liu, Huiying.,Chung, Haegeun.,Yu, Lingfei.,Mi, Zhaorong.,...&He, Jin-Sheng.(2014).Non-growing-season soil respiration is controlled by freezing and thawing processes in the summer monsoon-dominated Tibetan alpine grassland.GLOBAL BIOGEOCHEMICAL CYCLES.
MLA	Wang, Yonghui,et al."Non-growing-season soil respiration is controlled by freezing and thawing processes in the summer monsoon-dominated Tibetan alpine grassland".GLOBAL BIOGEOCHEMICAL CYCLES (2014).