Evaluating on Agricultural Practices for Effective Sediment Yield Reduction on Sugarcane Fields, Okinawa

Abstract

Soil erosion and runoff have led to agricultural and environmental problems throughout the world. Especially in tropical or subtropical region, the corals have been damaged due to oversupply of sediment and nutrients from the river basin including agricultural zones. Therefore effective treatments which can reduce sediment yield in the farmland are necessary. The authors have carried out field plot tests in sugarcane fields to compare the amounts of sediment yield depending on the difference of agricultural practices. From the observations, no-tillage, intercropping, and grass strip reduced sediment yield by 89%, 45%, and 17%, respectively. Moreover, the managements of perennial sugarcane farming and combination of strip tillage planting and intercropping were found to reduce sediment yield by 85% and 69%, respectively. Therefore a sugarcane farming cycle combining these two managements is supposed to be the best-case scenario to reduce sediment yield.