云南松松针水势日变化的研究

A Study on the Daily Water Fluctuation of Water Potential in Pinus Yunnanensis Needles

本文跟踪测定了云南松松针水势的日变化，研究了水势的变化与气温、光照、湿度变化之间的相互关系．结果表明水势与气温和光照呈负相关，与湿度呈正相关．同时还表明松针水势具有白天降低，夜间升高的变化规律．我们认为测定水势的最佳时间是凌晨露点前．

Based on the examination of the daily water potential fluctuation in Pinus yunnanensis needles,focuses on the relationship between the water potential and the air temperature,the soil temperature,the intensity of illumination and the humidity have been studied.The water potential has a negative correlation to the air temperature and the intensity of illumination,and a positive correlation to the humidity.It is discovered that the potential has a diurnal decrease and a nocturnal increase.It is therefore proposed that the predawn is the proper time to measure the water potential.