Use of palm fronds as shaded cover for evaporation reduction to improve water storage efficiency

Abstract

Water bodies in arid surroundings can be subject to high evaporation losses due to oasis effect. Evaporation raises the storage requirements of water bodies and lowers the yield. Covering of water bodies can help in reducing evaporation. The work presented in this study aims at investigating the use of palm fronds as shaded cover for the reduction of evaporation from the open water surface so as to increase the storage efficiency. The material used for cover was locally available palm fronds which are a massive agricultural waste and environmental friendly by-product in Saudi Arabia. Pan evaporimeters were used in the present study. One pan was covered like a shade made of palm fronds, which were tied up on mesh wiring while the other was kept without any cover. Initially a single layer of cover was used as shaded cover which was replaced by a cover of two layers of palm fronds in order to see the effect of thickness of cover on overall evaporation. It was observed that the average reduction in evaporation in the covered pan (with single layer of cover) was about 47% as compared to the evaporation from the open pan. However, the average reduction in evaporation in the covered pan (with double layer of cover) was about 58% as compared to the evaporation from the open pan.