基于互补相关原理的三江平原蒸散发时空变化规律分析

Spatiotemporal Variation of Evapotranspiration in the Sanjiang Plain based on Complementary Relationship

研究蒸散发的变化对灌溉水分管理和水资源利用有重要作用。三江平原是中国重要的农业区,灌溉用水量巨大。研究的目的是探讨三江平原蒸散发的变化趋势,为水资源可持续发展提供科学依据。研究选用了3种基于互补相关原理的蒸散发模型,比较了其在估算三江平原蒸散发(ET_A)时的精度,并根据水量平衡方程对蒸散发模型进行参数调整,最终选择精度最高的模型用于估算1960-2020年三江平原ET_A。研究采用了多种分析方法,Mann-Kendall检验和反距离权重法用于讨论ET_A时空变化规律,相关系数和单因素敏感性分析法用于讨论气象因素对ET_A的影响。结果表明,使用原始参数值的3种蒸散发模型在估算ET_A时误差较大,在对3种模型的参数进行调整后,互补相关陆面蒸散模型表现出更高的准确性,成为估算三江平原ET_A的最优模型;三江平原年ET_A在61年间处于显著上升趋势,线性增长速率为0.4mm/a,夏季ET_A的变化趋势与年ET_A一致,其余季节的ET_A变化趋势不同,夏季ET_A的上升是影响年ET_A上升的最主要因素;ET_A的空间分布不同,多年平均值和季节平均值集中出现在三江平原的中部区域,三江平原东部ET_A的上升速率快于中部和西部区域;最低气温与ET_A的相关性最强,风速与ET_A的相关性最弱,ET_A对气温变化敏感,最高气温的变化对ET_A的影响程度最大。

Evapotranspiration change research is important for irrigation water management and water resources utilization.The Sanjiang Plain,as a vital agricultural region in China,faces substantial demands for irrigation water.The primary objective of this study is to investi⁃gate the trends in evapotranspiration(ETA)in the Sanjiang Plain,and to provide a scientific basis for the sustainable development of water re⁃sources in this area.In this study,we selected three evapotranspiration models based on the complementary relationship principle and com⁃pared their accuracy in estimating ETA in the Sanjiang Plain,then adjusted and validated the parameters of the models based on the water bal⁃ance equations.Ultimately,the model with the highest accuracy was selected for estimating the ETA in the Sanjiang Plain from 1960 to 2020.Various analytical methods were employed,including the Mann-Kendall test and the inverse distance weighting method,to explore the spa⁃tiotemporal patterns of ETA.Furthermore,correlation coefficients and single-factor sensitivity analysis were used to assess the influence of meteorological factors on ETA.The results showed that when using the original parameter values,the three evapotranspiration models intro⁃duced substantial errors in estimating ETA.However,after parameter adjustments,the complementary relationship areal evapotranspiration model exhibited superior accuracy and was selected as the optimal model for estimating ETA in the Sanjiang Plain.Over the 61-year period,the annual ETA in the Sanjiang Plain is in a significant upward trend with a linear growth rate of 0.4 mm per year.The change trend of summer ETA is consistent with the annual ETA,and the change trend of ETA in other seasons is different.The rising trend in summer ETA was the domi⁃nant factor contributing to the increase in annual ETA.The spatial distribution of ETA exhibited variations,with multi-year and seasonal aver⁃ages predominantly concentrated in the central region of the Sanjiang Plain.The ETA increase rate of the eastern part is faster than the central and western parts in the Sanjiang Plain.The minimum temperature exhibited the strongest correlation with ETA,while wind speed had the weakest correlation.ETA demonstrated sensitivity to temperature changes,with variations in maximum temperature having the most signifi⁃cant impact.