Sap flow characteristics in growing and non-growing seasons in three tree species in the semiarid Loess Plateau region of China,Trees

当前位置： X-MOL 学术 › Trees › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Sap flow characteristics in growing and non-growing seasons in three tree species in the semiarid Loess Plateau region of China
Trees ( IF 2.3 ) Pub Date : 2020-04-18 , DOI: 10.1007/s00468-020-01972-1
Jinlin Lyu , Qiu-Yue He , Jie Yang , Qiu-Wen Chen , Ran-Ran Cheng , Mei-Jie Yan , Norikazu Yamanaka , Sheng Du

Key message

Year-round observation suggests that sap flow in growing season represents species-specific transpiration characteristics and sap flow of deciduous broadleaved species in non-growing season is related to daily changes in stem diameter.

Abstract

Year-round observation is necessary to investigate species-specific characteristics of sap flow and its possible contribution in non-growing season. The middle Loess Plateau in China is characterized by temperate climate and vegetation cover of generally drought-tolerant deciduous broadleaved and some evergreen coniferous trees. In this study, Granier-type thermal dissipation probes were applied to measure year-round xylem sap flow in three species from April 2017 to April 2018. Solar radiation, air temperature, relative air humidity, precipitation, and soil moisture were monitored continuously. The results showed that the peak time of sap flux density (F_d) in the diurnal courses of Robinia pseudoacacia was later than that of Quercus liaotungensis and Platycladus orientalis. The peak time of F_d for R. pseudoacacia was significantly postponed during the period with higher soil moisture when compared with that at lower soil moisture, whereas the peak time was reached slightly earlier in the other two species. Sap flow during the non-growing season was relatively higher in P. orientalis than in the two broadleaved species. The diurnal course of F_d in non-growing season showed high values at nighttime and low values in daytime, opposite to that in growing season. Daily variation in stem diameter was inverse of the change in sap flow in the two broadleaved species, whereas the daily change in stem diameter of P. orientalis was very small and showed no clear relation with sap flow. The results suggest that changes in transpiration characteristics with soil moisture conditions vary with tree species; sap flow in deciduous broadleaved trees in non-growing season is small and closely related to daily changes in stem diameter.

更新日期：2020-04-18

点击分享查看原文

点击收藏

阅读更多本刊最新论文

全部期刊列表>>