生态学杂志2025，Vol.44Issue(4)：1114-1124,11.DOI:10.13292/j.1000-4890.202504.048
夏季干旱期沙柳昼夜蒸腾耗水特征及其对气象因子的响应
Diurnal and nocturnal water use characteristics and the response to meteorological factors in Salix psam-mophila during the summer drought period
摘要
Abstract
To gain deep insights into shrub water use patterns and its response mechanism to environmental chan-ges,it is essential to investigate the strategies of diurnal and nocturnal water use ratio by Salix psammophila under different moisture conditions.Three irrigation treatments were set in summer drought periods,including full irriga-tion(T25,irrigated when the soil water potential at 20 cm directly below the dripper reached-25 kPa),water-con-trolled irrigation(T50,irrigated when the soil water potential at 20 cm directly below the dripper reached-50 kPa),and no irrigation(CK,control).Environmental factors and the rate of sap flow in branches from different orientations were synchronously and continuously monitored.Plant water use was calculated based on the extension of branch base diameter in typical S.psammophila artificial forest of Hobq Desert.Results showed that there was a significant advantage in sap flow in the north direction of S.psammophila under T25,and no significant advantage under other treatments.During the summer drought periods,the daytime water use(Qd)and nocturnal water use(Qn)of group T25 increased by 255.6％and 72.7％,respectively,and the proportion of Qn reduced from 4.0％to 2.0％.There was a significant positive correlation between the Qd of T25 and soil moisture(θ)of the 0-40 cm soil depth(P≤0.01).There was a significant negative correlation between Qn and θ in the 40-60 cm soil layer(P≤0.05).The correlation betweenQdand Qn in the controlled irrigation group and θ was not significant.The effects of vapor pressure deficit and relative air humidity on Qd and Qn decreased with increasing θ.Precipitation positively affected Qn by increasing soil moisture(P≤0.05).We concluded that water use of S.psammophila can be derived well from the branch diameter,which was less affected by the branch orientation.The diurnal and nocturnal water use of S.psammophila was 0.27 to 0.96 mm·d-1 and 0.009 to 0.019 mm·d-1,respectively,indicating different adaptation to short-term and long-term soil moisture supply.Full irrigationdid not alter the nocturnal water use habits of S.psammophila.关键词
干旱区/灌木/耗水量/土壤含水率/权衡Key words
arid region/shrub/water use/soil moisture content/trade-off引用本文复制引用
孙凯,裴志永,郝一军,王海超,孙小添,杨建军,王鑫平,韩兆敏..夏季干旱期沙柳昼夜蒸腾耗水特征及其对气象因子的响应[J].生态学杂志,2025,44(4):1114-1124,11.基金项目
国家自然科学基金项目(52069018和32301665)、内蒙古自治区科技重大专项项目(2021ZD0008)和内蒙古自治区自然科学基金项目(2024QN03026和2023QN03029)资助. （52069018和32301665）
