Sap flow changes and climatic responses over multiple-year treatment of rainfall exclusion in a sub-humid black locust plantation

Qiu Yue He, Mei Jie Yan, Yoshiyuki Miyazawa, Qiu Wen Chen, Ran Ran Cheng, Kyoichi Otsuki, Norikazu Yamanaka, Sheng Du

研究成果: Contribution to journalArticle査読

9 被引用数 (Scopus)

抄録

Black locust (Robinia pseudoacacia) plantations have been widely established in the semiarid and sub-humid areas of central China. Under the condition of global climate change, which is introducing much uncertainty of precipitation patterns in this region, it is of special significance to investigate their responses to precipitation. Here, we investigated sap flow response to reduced throughfall. Stem sap flow was measured from 2011 to 2017 using Granier-type sensors. By placing waterproof panels within tree rows, about 47.5% precipitation was excluded from treated plots since April 2015. Differences in soil water content gradually increased to 4.3% between treated and control plots with continued throughfall exclusion. Decreased precipitation input significantly reduced the average sap flux density in treated plots by 9.1%–45.3%. The extent of this reduction depended on precipitation in the previous and current years. Transpiration and forest growth were negatively affected by the treatment. Furthermore, sap flow response to environmental factors became insensitive, with the discrepancy increasing with increasing drought duration, but was regained by rainfall recharge to soil water in the first two treatment years. However, prolonged drought might damage transpiration resilience capacity, as the saturated sap flux after soil water recharging during the wet period was still lower than that in the control plot in the latter year. Predawn leaf water potential was significantly lower in the treated plot compared to the control plot, whereas midday leaf water potential was similar. Whole tree hydraulic conductance (GP) was also similar between the two plots, except in extreme drought months when GP was much lower in the treated plot. In addition, the specific leaf area and stomatal density decreased in the treated plot. Therefore, decreases in precipitation would cause a transpiration reduction, weakening the tree's response to meteorological variables and lowering growth and productivity, potentially damaging transpiration resilience. These results suggest that black locust is sensitive to water changes, its capacity of drought tolerant is restrained by the drought time scale or drought severity, the use of such species in reforestation in semiarid regions should be implemented with caution.

本文言語英語
論文番号117730
ジャーナルForest Ecology and Management
457
DOI
出版ステータス出版済み - 2 1 2020

All Science Journal Classification (ASJC) codes

  • 林業
  • 自然保全および景観保全
  • 管理、モニタリング、政策と法律

フィンガープリント

「Sap flow changes and climatic responses over multiple-year treatment of rainfall exclusion in a sub-humid black locust plantation」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル