干旱区生态环境知识资源中心(Arid): 灌水和放牧对荒漠草原生态系统碳交换的影响

Arid

	灌水和放牧对荒漠草原生态系统碳交换的影响
其他题名	Water Manipulations Altered Grazing Effects on Carbon Exchange in a Desert Steppe
	刘倩 1; 张方敏 1; 陈吉泉 2; 赵晓涵 1; 景元书 1
来源期刊	中国农业气象
ISSN	1000-6362
出版年	2019
卷号	40 期号:12 页码:737-746
中文摘要	依托内蒙古乌兰察布市四子王旗境内短花针茅荒漠草原的10a放牧强度(不放牧、轻度放牧、重度放牧)试验平台,于2012年和2013年在荒漠草原生长季(5-10月),设计放牧嵌套灌水的控制试验,以不灌水和不放牧为对照,研究净生态系统碳交换速率(net ecosystem exchange,NEE)、净生态系统呼吸速率(ecosystem respiration, RE)和总生态系统碳交换速率(gross ecosystem exchange, GEE)对不同水分条件(灌水、非灌水)和不同放牧强度的响应。结果表明:(1)荒漠草原生长季表现为净碳吸收(NEE和GEE<0)。不放牧条件下灌水通过增加土壤体积含水量(soli volumetric water content,Vwc)间接增加RE和生态系统碳吸收(P<0.01), NEE、RE和GEE对灌水带来的土壤水分变化较为敏感。(2)不灌水条件下,NEE、RE和GEE在不同放牧强度处理中的差异并不显著,但8月后放牧带来的DeltaNEE和DeltaGEE正偏差显著大于8月前的负偏差(P<0.001)。(3)灌水和放牧的交互作用对NEE、RE和GEE均无显著影响,但放牧条件下增加Vwc可以增加生态系统碳吸收和呼吸作用。区分放牧强度时,RE和GEE对Vwc的线性回归模型斜率的绝对值在不放牧时最大(分别为0.26和0.61),说明放牧导致荒漠草原生态系统碳交换对土壤水分变化的敏感性减小。
英文摘要	Based on a long term grazing experiment(10 years) that includes no grazing(CK), light grazing(LG) and heavy grazing(HG) over a Stipa breviflora desert steppe in Siziwang, Wulanchabu, Inner Mongolia, China, a manipulative experiment of water input was conducted during 2012-2013. The grazing plots were treated as the block factor for nested water treatments. We aimed at exploring the responses of net ecosystem exchange(NEE), ecosystem respiration(RE) and gross ecosystem exchange(GEE) of carbon under two water additions: irrigation vs no-irrigation. We found that:(1) the desert steppe was a net carbon sink. Irrigation indirectly increased RE and the ecosystem carbon sink by elevating soil volumetric water content(Vwc) without grazing(P<0.01). NEE, RE and GEE were found to be more sensitive to Vwc due to irrigation(P<0.001).(2) The differences in NEE, RE and GEE among the grazing treatments were not significant under no-irrigation treatment, whereas positive deviations of DeltaNEE and DeltaGEE with grazing after August were significantly greater than the negative deviations before August(P<0.001).(3) The interactive contributions from irrigation and grazing treatments produced no significant effect on NEE, RE and GEE, but increased Vwc under grazing that enhanced ecosystem carbon sink and RE. When the grazing intensity was explored, both the magnitudes and changes of RE and GEE with Vwc at grazed sites were higher than those at no grazing plots(0.26 and 0.61, respectively), indicating that grazing resulted in a decrease in the sensitivity of carbon exchange to Vwc.
中文关键词	灌水 ; 土壤体积含水量 ; 放牧强度 ; 荒漠草原 ; 生态系统碳交换
英文关键词	Irrigation Soil volumetric water content Grazing intensity Desert steppe Ecosystem carbon exchange
语种	中文
收录类别	CSCD
WOS类目	AGRICULTURE MULTIDISCIPLINARY
WOS研究方向	Agriculture
CSCD记录号	CSCD:6632387
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/316260
作者单位	1.南京信息工程大学/应用气象学院, 气象灾害预报预警与评估协同创新中心;;江苏省农业气象重点实验室, 南京, 江苏 210044, 中国; 2.密歇根州立大学地理环境空间科学系全球变化观测中心, 东兰辛, 4825, 美国
推荐引用方式 GB/T 7714	刘倩,张方敏,陈吉泉,等. 灌水和放牧对荒漠草原生态系统碳交换的影响[J],2019,40(12):737-746.
APA	刘倩,张方敏,陈吉泉,赵晓涵,&景元书.(2019).灌水和放牧对荒漠草原生态系统碳交换的影响.中国农业气象,40(12),737-746.
MLA	刘倩,et al."灌水和放牧对荒漠草原生态系统碳交换的影响".中国农业气象 40.12(2019):737-746.