Monsoonal Influence on Evapotranspiration of the Tropical Mangrove Forest in Northeast India

Abstract

Evapotranspiration (ET) is an important part of the water cycle. This study reports on the mon-soonal influence on the temporal variation in evapotranspiration of an extremely water conservative and salinity stressed tropical mangrove forest at the land-ocean boundary of northeast coast of India. The magnitude and dynamics of evapotranspiration (ET) exhibited seasonality dominated by monsoon and evaporation rate was greater (0.055 ± 0.015 g•m −2 •s −1) during the monsoon than in pre-monsoon (0.049 ± 0.018 g•m − 2 •s −1) and post-monsoon (0.044 ± 0.012 g•m −2 •s −1). Seasonal difference in evapotranpiration was mostly due to fluctuation of canopy resistance, which was the minimum during monsoon when relative humidity was greater than in the dry season (pre-and post-monsoon) and deficiency of water supply (ET ≈ ETeq) was minimum. Evapotranspiration in the Sundarban mangrove ecosystem is the predominant biophysical processes that recycles 67.7% of total precipitation annually to the atmosphere, and has significant monsoonal influence.