Grazing intensity alters soil respiration in an alpine meadow on the Tibetan plateau

NWIPB OpenIR

	Grazing intensity alters soil respiration in an alpine meadow on the Tibetan plateau
	Cao, GM ; Tang, YH ; Mo, WH ; Wang, YA ; Li, YN ; Zhao, XQ
	2004-02-01
发表期刊	SOIL BIOLOGY & BIOCHEMISTRY ; Cao Guangmin, Tang Yanhong, Mo Wenhong, Wang Yuesi, Li Yingnian, Zhao Xinquan.Grazing intensity alters soil respiration in an alpine meadow on the Tibetan plateau. SOIL BIOLOGY & BIOCHEMISTRY,2004,36(2):237-243
摘要	Grazing intensity may alter the soil respiration rate in grassland ecosystems. The objectives of our study were to (1) determine the influence of grazing intensity on temporal variations in soil respiration of an alpine meadow on the northeastern Tibetan Plateau; and (2) characterise, the temperature response of soil respiration under different grazing intensities. Diurnal and seasonal soil respiration rates were measured for two alpine meadow sites with different grazing intensities. The light grazing (LG) meadow site had a grazing intensity of 2.55 sheep ha(-1), while the grazing intensity of the heavy grazing (HG) meadow site, 5.35 sheep ha(-1), was approximately twice that of the LG site. Soil respiration measurements - showed that CO2 efflux was almost twice as great at the LG site as at the HG site during the growing season, but the diurnal and seasonal patterns of soil respiration rate were similar for the two sites. Both exhibited the highest annual soil respiration rate in mid-August and the lowest in January. Soil respiration rate was highly dependent on soil temperature. The Q(10) value for annual soil respiration was lower for the HG site (2.75) than for the LG site (3.22). Estimates of net ecosystem CO2 exchange from monthly measurements of biomass and soil respiration revealed that during the period from May 1998 to April 1999, the LG site released 2040 g CO2 m(-2) y(-1) to the atmosphere, which was about one third more than the 1530g CO2 m(-2) y(-1) released at the HG site. The results suggest that (1) grazing intensity alters not only soil respiration rate, but also the temperature dependence of soil CO2 efflux; and (2) soil temperature is the major environmental factor controlling the temporal variation of soil respiration rate in the alpine meadow ecosystem. (C) 2003 Elsevier Ltd. All fights reserved.; Grazing intensity may alter the soil respiration rate in grassland ecosystems. The objectives of our study were to (1) determine the influence of grazing intensity on temporal variations in soil respiration of an alpine meadow on the northeastern Tibetan Plateau; and (2) characterise, the temperature response of soil respiration under different grazing intensities. Diurnal and seasonal soil respiration rates were measured for two alpine meadow sites with different grazing intensities. The light grazing (LG) meadow site had a grazing intensity of 2.55 sheep ha(-1), while the grazing intensity of the heavy grazing (HG) meadow site, 5.35 sheep ha(-1), was approximately twice that of the LG site. Soil respiration measurements - showed that CO2 efflux was almost twice as great at the LG site as at the HG site during the growing season, but the diurnal and seasonal patterns of soil respiration rate were similar for the two sites. Both exhibited the highest annual soil respiration rate in mid-August and the lowest in January. Soil respiration rate was highly dependent on soil temperature. The Q(10) value for annual soil respiration was lower for the HG site (2.75) than for the LG site (3.22). Estimates of net ecosystem CO2 exchange from monthly measurements of biomass and soil respiration revealed that during the period from May 1998 to April 1999, the LG site released 2040 g CO2 m(-2) y(-1) to the atmosphere, which was about one third more than the 1530g CO2 m(-2) y(-1) released at the HG site. The results suggest that (1) grazing intensity alters not only soil respiration rate, but also the temperature dependence of soil CO2 efflux; and (2) soil temperature is the major environmental factor controlling the temporal variation of soil respiration rate in the alpine meadow ecosystem. (C) 2003 Elsevier Ltd. All fights reserved.
文献类型	期刊论文
条目标识符	http://210.75.249.4/handle/363003/50875
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	Cao, GM,Tang, YH,Mo, WH,et al. Grazing intensity alters soil respiration in an alpine meadow on the Tibetan plateau[J]. SOIL BIOLOGY & BIOCHEMISTRY, Cao Guangmin, Tang Yanhong, Mo Wenhong, Wang Yuesi, Li Yingnian, Zhao Xinquan.Grazing intensity alters soil respiration in an alpine meadow on the Tibetan plateau. SOIL BIOLOGY & BIOCHEMISTRY,2004,36(2):237-243,2004.
APA	Cao, GM,Tang, YH,Mo, WH,Wang, YA,Li, YN,&Zhao, XQ.(2004).Grazing intensity alters soil respiration in an alpine meadow on the Tibetan plateau.SOIL BIOLOGY & BIOCHEMISTRY.
MLA	Cao, GM,et al."Grazing intensity alters soil respiration in an alpine meadow on the Tibetan plateau".SOIL BIOLOGY & BIOCHEMISTRY (2004).