摘要
蒸散发(Evapotranspiration,ET)是陆地与大气系统中水循环与能量交换的重要因素。为了提高估算区域尺度ET的精度,更加准确的为气候演变研究、水资源管理、环境保护等提供现实数据与理论支撑,论文基于2017—2018年Landsat8 OLI遥感影像与气象站数据,运用SEBS (Surface Energy Balance System)模型估算河套灌区日尺度蒸散发,采用Penman-Monteith公式计算结果对其进行精度验证,并探讨其时空变化特征及驱动力。结果表明:(1) SEBS模型估算值与彭曼公式计算的5个气象站的平均相对误差分别为15.07%、17.94%、16.17%、9.93%、13.18%,表明估算研究区日尺度蒸散发可以基于SEBS模型实现,并且估算效果较好。(2)研究区内ET空间上呈现纬度递减变化,ET随着纬度的降低呈增大的趋势。(3)基于SEBS模型得到的日蒸散量与NDVI、地表反照率、地表温度等3个地表参数拟合系数从大到小依次排序为:地表温度>地表反照率>NDVI。(4)日尺度SEBS模型得到的蒸散发与气象因素进行主成分分析,与第一主成分密切相关的驱动因子为气温,方差贡献率为40.434%。综合可见, SEBS模型能够很好的对河套灌区蒸散发进行模拟,模拟潜在蒸散发量具有明显的年内分配特征,在4—10月中整体表现为先增大再减小趋势,ET最高值出现在7月, ET的主要特征影响因子为气温。
Evapotranspiration(ET)is an important factor of water cycle and energy exchange between terrestrial and atmospheric systems.It aims to improve the accuracy of regional scale ET estimation and provide more accurate data and theoretical support for climate change research,water resources management and environmental protection,based on the Landsat8 OLI remote sensing image and weather station data from 2017 to 2018.The results showed that:(1)the average relative errors of SEBS model and Penman formula were 15.07%,17.94%,16.17%,9.93%and 13.18%,indicating that the estimation of daily evapotranspiration in the study area could be realized based on SEBS model,and the estimation effect was good.(2)In the study area,the ET space showed a decreasing trend of latitude,and the ET increased with the decrease of latitude.(3)Based on SEBS model,the fitting coefficients of daily evapotranspiration with NDVI,surface albedo and surface temperature were ranked as surface temperature>surface albedo>NDVI.(4)Principal component analysis showed that the driving factor closely related to the first principal component was air temperature,and the variance contribution rate was 40.434%.It can be seen that SEBS model can well simulate the evapotranspiration of Hetao Irrigation District,and the simulated potential evapotranspiration has obvious annual distribution characteristics,which first increases and then decreases from April to October.The highest value of ET appears in July,and the main characteristic influencing factor of ET is temperature.
作者
张志胤
李瑞平
王秀青
王燕鑫
贾博中
ZHANG zhiyin;LI Ruiping;WANG xiuqing;WANG yanxin;JIA bozhong(College of Water Conservancy and Civil Engineering,Inner Mongolia Agricultural University,Hohhot 010018,China;The Inner Mongolia mapping and Geographic Information Center,Hohhot 010010,China)
出处
《生态科学》
CSCD
2023年第4期9-17,共9页
Ecological Science
基金
国家自然科学基金项目(51769021,51839006)。
