摘要
应用先进的PHYTALK植物生理生态监测系统对塔里木河下游英苏断面胡杨的茎流、相关环境因子以及茎直径的日变化进行了监测。结果表明:在极端干旱区塔里木河下游的胡杨茎流日变化表现多峰值,且夜晚仍保持一定流速;茎流变化受太阳辐射、风速和大气温度影响明显,而其它环境因子如空气湿度、土壤湿度等影响则不大;同时,日变化中,不同时段起主导作用的因子不尽相同。胡杨茎直径对植株水分状况响应灵敏,夜晚植株组织含水充足,茎直径相对较大,白天植株失水,茎直径减小;胡杨随着干旱胁迫程度的增加,茎直径日最大值和最小值都显明显下降趋势。
The sap flow rate of Populus euphratica, relative environmental factors and the variation of stem diameters have been observed for 3 days at Yingsu in the lower reaches of Tarim river with advanced PHYTALK system. The results showed the following regularities： the diurnal variation of sap flow rate of Populus euphratica appears multl-peaks; there is still sap flow in night; the net radiation, air temperature and wind speed play critical role to affect sap flow; however, soil humidity and air humidity have minor influence on it; furthermore, during the diurnal variation of sap flow, different periods have different determinants; the variation of stem diameters could respond sensitively to plant moisture content condition; the water of plant tissue is abundant at night but scarce at daytime, accordingly the stem diameter is thicker at night than at daytime; moreover, the maximum and minimum of stem diameter decreased during drought period.
出处
《干旱区地理》
CSCD
北大核心
2007年第2期223-230,共8页
Arid Land Geography
基金
中国科学院知识创新项目
国家自然科学基金(90502007
30500081)资助
关键词
胡杨
茎流
茎直径
干旱胁迫
塔里木河
Populus euphratica
sap flow
stem diameter
drought stress
the Tarim river
