西双版纳人工橡胶林冠层温度及其影响因子

Canopy temperature and its drivers of rubber plantation in Xishuangbanna,Southwest China

冠层温度(T_(c))是衡量植物水分和热量的关键生理生态指标之一。本研究以西双版纳地区橡胶林为对象,利用红外温度传感器及常规气象监测数据,分析了2014—2016年橡胶林冠层温度和气象因子的变化,旨在揭示西双版纳地区橡胶林冠层温度的变化特征及其与气象因子之间的关系。结果表明:T_(c)的年变化和干季日变化特征都呈现出单峰趋势,而雨季日变化呈现出双峰趋势。T_(c)与各气象因子的相关性为:大气温度>饱和水汽压差>净辐射>风速>相对湿度>降水量,其中,大气温度与T_(c)的相关性最强(r=0.92,P<0.01,n=1096)。偏相关分析发现,大气温度、净辐射和饱和水汽压差对干、雨两季的T_(c)都有显著影响,但干季影响T_(c)的因素主要是大气温度和净辐射,雨季影响T_(c)的主要因素是大气温度和饱和水汽压差。本研究初步得出了西双版纳地区冠层温度的变化特征及其与气象因子的关系,为深入探究冠层温度的影响因子提供了基础。

Canopy temperature(T) is one of the key ecophysiological indices to measure plant moisture and heat. In this study, we measured Tand other meteorological parameters(air temperature, precipitation, relative humidity, vapor pressure deficit, net radiation, and wind speed) during 2014 to 2016 in a rubber plantation, Xishuangbanna, Southwest China. We aimed to reveal the variations of Tand its relationship with meteorological factors. The results showed that the diurnal variation of Texhibited a single peak in dry season and bimodal trend in rainy season. The annual variation of Tshowed a unimodal trend. The Twas higher in rainy season than that in dry season. Furthermore, the mean Twas always higher than air temperature throughout the year. The correlation between Tand meteorological factors was as follows: air temperature>vapor pressure deficit>net radiation>wind speed>relative humidity>precipitation, with air temperature having the strongest effects on T(r=0.92, P<0.01, n=1096). Partial correlation analysis showed that air temperature, net radiation and vapor pressure deficit had significant effects on Tin both rainy and dry seasons. The main factors influencing Twere air temperature and net radiation in dry season, whereas air temperature and vapor pressure deficit were main factors for rainy season. This study manifested the variation characteristics of Tand its relationship with meteorological factors in Xishuangbanna, which provided a basis for understanding the affecting factors of T.