拆分典型草原群落蒸散组分方法研究  

The Study on Methods of Separating Evapotranspiration Components of Typical Grassland Plant Communities

作　　者：张泽 孙贺阳[1,2,3] 李陶珂 郑云暖 王敏 杨劼 清华[1,2,3] 包铁军 ZHANG Ze;SUN He-yang;LI Tao-ke;ZHENG Yun-nuan;WANG Min;YANG Jie;QING Hua;BAO Tie-jun(School of Ecology and Environment,Inner Mongolia University,Hohhot 010021,China;Key Laboratory of Ecology and Resource Use of the Mongolian Plateau of Ministry of Education,Hohhot 010021,China;Key Laboratory of Grassland Ecology of Inner Mongolia,Hohhot 010021,China)

机构地区：[1]内蒙古大学生态与环境学院,内蒙古呼和浩特010021 [2]蒙古高原生态学与资源利用教育部重点实验室,内蒙古呼和浩特010021 [3]省部共建草地生态学重点实验室,内蒙古呼和浩特010021

出　　处：《中国草地学报》2021年第4期87-95,共9页Chinese Journal of Grassland

基　　金：内蒙古自治区科技专项(2019ZD002、2020SZD0031);国家自然科学基金项目(31560174、32060268);内蒙古自然科学基金(2018MS03072)。

摘　　要：在内蒙古锡林郭勒典型草原,采用氢氧稳定同位素法和微型蒸渗仪法,分别对典型草原群落蒸散通量进行观测和拆分,以期为草原群落的蒸腾、蒸发观测方法的选择提供参考依据。结果表明:水汽同位素组成随高度增加逐渐减小,每次较大的降雨过程都会导致水汽同位素组成显著降低。环境因素尤其是相对湿度对土壤蒸发同位素组成的计算会产生较大影响,土壤水同位素组成较土壤蒸发水汽同位素组成发生显著富集。在11:30~14:30时段,微型蒸渗仪与稳定同位素方法拆分结果非常接近,蒸腾/蒸散(F T)值分别为80.86%和78.07%,说明应用水同位素法在草原生态系统进行蒸散拆分是可行的。以上两种方法的F T值在5~9月均呈抛物线趋势,在7月中旬至8月底达到峰值。To provide basis for the selection of methods for observation of transpiration and evaporation of typical grassland plant communities,the hydrogen and oxygen stable isotope method and the micro-lysimeter method were used to observe and separate the evapotranspiration components of plant communities in the typical grassland of Xilin Gol in Inner Mongolia.The results showed that the isotopic composition of water vapor gradually decreased with the increase in altitude,and the water vapor isotopic composition was decreased significantly with each heavy rainfall.Environmental factors,especially relative humidity,have a greater impact on the calculation of soil evaporative isotope composition.Due to the isotope fractionation effect,the isotopic composition of soil water was significantly enriched compared with that of soil evaporation water vapor.From 11:30 to 14:30,the separation results of the micro-lysimeter and isotopic method were similar that the ratio of transpiration to evaporation(F T)values derived from above methods were 80.86%and 78.07%,respectively.This indicated that the water isotope method was a feasible way to separate the evapotranspiration in the grassland ecosystem.The F T value of the above two methods showed a parabolic trend from May to September,which reached the peak from the middle of July to the end of August.

关 键 词：典型草原 蒸散拆分 稳定同位素 微型蒸渗仪 

分 类 号：Q948.1[生物学—植物学]