干旱区生态环境知识资源中心(Arid): Sap flow characteristics and physiological adjustments of two dominant tree species in pure and mixed plantations in the semi-arid Loess Plateau of China

Arid

	Sap flow characteristics and physiological adjustments of two dominant tree species in pure and mixed plantations in the semi-arid Loess Plateau of China
	Tang Yakun; Wu Xu; Chen Yunming
来源期刊	Journal of Arid Land
ISSN	1674-6767
出版年	2018
卷号	10 期号:6 页码:833-849
英文摘要	It is essential to understand the water consumption characteristics and physiological adjustments of tree species under drought conditions, as well as the effects of pure and mixed plantations on these characteristics in semi-arid regions. In this study, the normalized sap flow (SF_n), leaf water potential, stomatal conductance (g_s), and photosynthetic rate (P_r) were monitored for two dominant species, i.e., Pinus tabuliformis and Hippophae rhamnoides, in both pure and mixed plantations in a semi-arid region of Chinese Loess Plateau. A threshold-delay model showed that the lower rainfall thresholds (R~L) for P. tabuliformis and H. rhamnoides in pure plantations were 9.6 and 11.0 mm, respectively, and the time lags (tau) after rainfall were 1.15 and 1.76 d for corresponding species, respectively. The results indicated that P. tabuliformis was more sensitive to rainfall pulse than H. rhamnoides. In addition, strong stomatal control allowed P. tabuliformis to experience low gs and Pr in response to drought, while maintaining a high midday leaf water potential (Psi_m). However, H. rhamnoides maintained high gs and Pr at a low Psim expense. Therefore, P. tabuliformis and H. rhamnoides can be considered as isohydric and anisohydric species, respectively. In mixed plantation, the values of RL for P. tabuliformis and H. rhamnoides were 6.5 and 8.9 mm, respectively; and the values of tau were 0.86 and 1.61 d for corresponding species, respectively, which implied that mixed afforestation enhanced the rainfall pulse sensitivity for both two species, especially for P. tabuliformis. In addition, mixed afforestation significantly reduced SFn, gs, and Pr for P. tabuliformis (P<0.05), while maintaining a high leaf water potential status. However, no significant effect of mixed afforestation of H. rhamnoides was observed at the expense of leaf water potential status in response to drought. Although inconsistent physiological responses were adopted by these species, the altered water consumption characteristics, especially for P. tabuliformis indicated that the mixed afforestation requires further investigation.
英文关键词	normalized sap flow physiological adjustments mixed afforestation Pinus tabuliformis Hippophae rhamnoides
类型	Article
语种	英语
开放获取类型	Bronze
收录类别	CSCD
WOS研究方向	Forestry
CSCD记录号	CSCD:6384002
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/336037
作者单位	Tang Yakun, Northwest A&F University, State Key Laboratory of Soil Erosion and Dry-land Farming on the Loess Plateau, Yangling, Shanxi 712100, China.; Chen Yunming, Northwest A&F University, State Key Laboratory of Soil Erosion and Dry-land Farming on the Loess Plateau, Yangling, Shanxi 712100, China.; Wu Xu, Institute of Soil and Water Conservation, Chinese Academy of Sciences and the Ministry of Water Resources;;University of Chinese Academy of Sciences, State Key Laboratory of Soil Erosion and Dry-land Farming on the Loess Plateau;;, Yangling;;, ;;Beijing 712100;;100049.
推荐引用方式 GB/T 7714	Tang Yakun,Wu Xu,Chen Yunming. Sap flow characteristics and physiological adjustments of two dominant tree species in pure and mixed plantations in the semi-arid Loess Plateau of China[J],2018,10(6):833-849.
APA	Tang Yakun,Wu Xu,&Chen Yunming.(2018).Sap flow characteristics and physiological adjustments of two dominant tree species in pure and mixed plantations in the semi-arid Loess Plateau of China.Journal of Arid Land,10(6),833-849.
MLA	Tang Yakun,et al."Sap flow characteristics and physiological adjustments of two dominant tree species in pure and mixed plantations in the semi-arid Loess Plateau of China".Journal of Arid Land 10.6(2018):833-849.