Simulation of evapotranspiration based on leaf area index, precipitation and pan evaporation: A case study of Poyang Lake watershed, China

Zihao Bian,Yan Gu,Jing Zhao,Ye Pan,Yongtai Li,C. Zeng,Lachun Wang

Published 2019 in International Journal of Ecohydrology and Hydrobiology

ABSTRACT

Abstract Evapotranspiration (ET) is a major component of land hydrological processes, where it determines the transfer of moisture and energy in the soil–vegetation–atmosphere system. In this study, an empirical ET model (PYH-ET) was established based on the relationships between the monthly ET and the leaf area index (LAI), precipitation (PRE), and pan evaporation (EVP) in the whole Poyang Lake watershed (China). Then, this model was applied to sub-watersheds of the Poyang Lake watershed and analyzed the contributions of the three variables to ET. The results showed that the correlation coefficients between the monthly ET and the monthly LAI, PRE, and EVP were 0.969, 0.380, and 0.894, respectively. The moving average of the PRE per 2 months was used to replace the monthly PRE as a variable in the model. The accuracy of the PHY-ET model was high where the R value for the model was 0.98 and the relative error of the model was 10.2% when the data of 2014 were used to validate the model built according to the data during 2000–2013. The contribution of LAI to ET was highest in all sub-watersheds, followed by EVP, whereas PRE made the lowest contribution. In addition, the contributions of these three factors to ET in this watershed conformed to the law of the minimum, where the variation in ET was limited by the factor with the smallest change. The proposed high accuracy empirical model requires a small number of readily available parameters and it is suitable for integration with hydrological models.

PUBLICATION RECORD

  • Publication year

    2019

  • Venue

    International Journal of Ecohydrology and Hydrobiology

  • Publication date

    Unknown publication date

  • Fields of study

    Environmental Science

  • Identifiers
  • External record

    Open on Semantic Scholar

  • Source metadata

    Semantic Scholar

CITATION MAP

EXTRACTION MAP

CLAIMS

  • No claims are published for this paper.

CONCEPTS

  • No concepts are published for this paper.

REFERENCES

Showing 1-36 of 36 references · Page 1 of 1

CITED BY

Showing 1-19 of 19 citing papers · Page 1 of 1