Estimation of throughfall in Pine tree (Pinus kesiya) in Meghalaya

In vegetated watersheds, 'throughfall' is an important hydrological input parameter. Throughfall is the part of rain water which finally reaches the ground after passing through the tree canopy. Measurement or estimation of throughfall is very important to study hydrology of land having forest cover. A study was conducted to estimate throughfall of Pine (Pinus kesiya) trees in Umiam, Meghalaya during 2002–2003. Pine was selected for the study because of its predominance in the hills of Meghalaya. Rains of different intensities were observed and weighted intensities were computed in case of successive storm events. Throughfall was found to increase with increase in the amount and intensity of rainfall. Linear relationships of rainfall amount versus throughfall and rainfall intensity versus throughfall were obtained with correlation coefficients of 0.98 and 0.61 respectively. However, correlation coefficients being low in case of rainfall intensity, it could be concluded that throughfall depends much on rainfall amount than on its intensity.