兴隆山青扦液流特征及其与环境因子的关系

Characteristics of the sap flow of Picea wilsonii and its environmental influence factors in the Xinglong Mountain

在2018年5月1日-10月31日,对兴隆山青扦树干液流、气象因子、土壤温湿度和土壤电导率进行连续监测,分析监测期内青扦液流特征及其与环境因子之间的关系.结果表明,不同时间尺度上青扦液流量均呈单峰变化,呈先增后减趋势,相比于晴天,青扦阴天液流启动时间和液流峰值出现时间均存在滞后现象.当年生长季内,青扦蒸腾总量为273.79 mm,日均蒸腾量1.49±0.71 mm.青扦夜间液流活动与日间液流量呈极显著相关.小时和日尺度上影响青扦液流的主要环境因子是土壤电导率和空气温度,可以分别解释78.4%和81.1%的液流量变异,饱和水汽压差是月尺度上的主要影响因子,可以解释月尺度97.3%的液流量变异.

SF-L probe based on the thermal diffusion method was used to continuously monitor the sap flow of Picea wilsonii and relational environmental factors at the same time in the Xinglong Mountain,including meteorological factors,soil electrical conductivity,soil temperature and humidity,so as to study the relationship between sap flow of P.wilsonii and its related environmental influencing factors during the study period.The results showed that sap flow manifested a single peak curve under different time scales;sap flow start time and peak exsiting time lagged on cloudy days.During the growing season,the total transpiration was 273.79 mm,with the daily transpiration being 1.49±0.71 mm.Nocturnal sap flow existed and was quite significantly related to daytime sap flow.The main environmental factors affecting sap flow on hourly and daily scales were soil electrical conductivity and air temperature,which could explain the change in sap flow by 78.4%and 81.1%,respectively,and vapor pressure deficit was the main environmental factor influencing sap flow on monthly scale,can explain the change of sapflow of 97.3%.