Establishment of rainfall partitioning parameters for tea plantations

Abstract

ABSTRACT Tea is a popular crop in Asia and Africa, yet only limited information on tea watershed hydrology is available. This study attempts to experimentally establish the rainfall partitioning parameters (RPPs), namely throughfall (TF), stemflow (SF), and rainfall interception (IC), for a plantation of 27-year-old tea plants grown in West Bengal, India. The relative proportions of TF, SF and IC were 59–89%, 0.12%, and 10–40% with coefficients of variation of 10%, 29%, and 27%, respectively. The SF proportion, being insignificant (≤2%), can be omitted. RPP responses were also analysed against rainfall depth, intensity, and duration. All RPPs except SF showed an exponential decay with rainfall depth. The fitted/validated models were evaluated for goodness of fit using coefficient of determination, mean absolute error, root mean square error, and Nash-Sutcliffe efficiency as error metrics. These results have pragmatic significance in tea watershed hydrology.