辽西北沙地樟子松树干液流的变化特征及其影响因素

生态学杂志

辽西北沙地樟子松树干液流的变化特征及其影响因素

卢志朋^1,2,魏亚伟^1,2,李志远^1,2,郭鑫炜^1,2,周永斌^1,2*#br#

（¹沈阳农业大学林学院，沈阳 110866； ^2辽宁辽河平原森林生态系统定位研究站，辽宁昌图 112500）

出版日期:2017-11-10 发布日期:2017-11-10

Characteristics of sap flow and its influencing factors of Pinus sylvestris var. mongolica in sandy land of Northwest Liaoning.

LU Zhi-peng^1,2, WEI Ya-wei^1,2, LI Zhi-yuan^1,2, GUO Xin-wei^1,2, ZHOU Yong-bin^1,2*#br#

(¹College of Forestry, Shenyang Agricultural University, Shenyang 110866, China; ²Research Station of LiaoheRiver Plains Forest Ecosystem, Changtu 112500, Liaoning, China).

Online:2017-11-10 Published:2017-11-10

摘要/Abstract

摘要： 树干液流是量化植物蒸腾耗水的基本指标。本研究于2015年5—10月采用FLGSTDP热扩散式树干液流计对辽西北半干旱区的沙地樟子松树干液流进行连续观测，同时结合林内小气候观测系统，探讨樟子松树干液流的动态变化特征及其影响因素。结果表明：树干液流速率和日累积量均为晴天＞阴天＞雨天，树干液流速率变化均呈“倒U”型，晴天时出现“光合午休”现象；不同月际间(5—10月)，树干液流速率与月累积量为7月＞6月＞8月＞5月＞9月＞10月；不同季节间，树干液流启动时间夏季比秋季早1 h左右，且树干液流速率夏季＞秋季。树干液流受气象因子的影响较大，其中光合有效辐射、空气温度、饱和水汽压差（VPD）和风速与树干液流呈显著正相关，空气相对湿度则相反；土壤温度和含水量对树干液流的影响较为复杂，随时间(月际)、天气状况(阴天、晴天和雨天)和土层深度(5、10、20、40和100 cm)的变化而变化，其中，生长季期间和不同月际间(5—10月)、表层土壤温度(0～10 cm)与树干液流均呈显著正相关，深层土壤(20～100 cm)则相反；生长季前(5月)和生长季末期(10月)，树干液流随土壤水分的增多而增加，生长季期间(6—9月)则相反，树干液流随土壤含水量的增加而减弱。

Abstract: Sap flow is a basic indicator to quantify plant transpiration water consumption. In this study, a continuous sap flow observation of Pinus sylvestris var. mongolica in a semiarid area of northwestern Liaoning was carried out by using the FLGS-TDP thermal dissipation sap flow probe from May to October in 2015, and the microclimate in the forest was recorded simultaneously. On the basis, the dynamic characteristics of the sap flow of Pinus sylvestris var. mongolica and its influencing factors were studied. Results showed that during the growing season, the sap flow rate of Pinus sylvestris var. mongolica varied with weather conditions, both the sap flow rate and its daily cumulative volume were decreased in the sequence of sunny > cloudy > rainy. The trend of sap flow rate followed reversed "U", and there was a phenomenon of "midday depression of photosynthesis" in sunny day. From May to October, both trunk sap flow rate and monthly accumulation amounts decreased as follows: July > June > August > May > September > October. With respect to the season dynamics, the starting hour of the trunk flow in summer was about an hour earlier than that in autumn; moreover, the trunk sap flow rate was higher in summer than in autumn. In addition, the sap flow was affected significantly by meteorological factors, in which the active radiation light, air temperature, saturated vapor pressure deficit and wind speed all affected sap flow positively, while the air humidity influenced sap flow negatively. The effects of soil temperature and humidity on the sap flow changed with time (month), weather conditions (cloudy, sunny and rainy) and soil depths (5, 10, 20, 40 and 100 cm). For example, there were significantly positive correlations between the temperature of surface soil (0-10 cm) and the sap flow (unit based on day or month) during the growing season, while there were significantly negative correlations between the temperature of deep soil (20-100 cm) and the sap flow. In addition, the sap flow increased significantly with the increase of soil moisture in May and October, while decreased remarkably with the increase of soil moisture during the growing season from June to September.

卢志朋1,2,魏亚伟1,2,李志远1,2,郭鑫炜1,2,周永斌1,2*. 辽西北沙地樟子松树干液流的变化特征及其影响因素[J]. 生态学杂志.

LU Zhi-peng1,2, WEI Ya-wei1,2, LI Zhi-yuan1,2, GUO Xin-wei1,2, ZHOU Yong-bin1,2*. Characteristics of sap flow and its influencing factors of Pinus sylvestris var. mongolica in sandy land of Northwest Liaoning.[J]. cje.