ASSESSMENT OF WATER REQUIREMENT OF TEN SELECTED CROPS CULTIVATED IN CESTOS RIVER BASIN GREENVILLE, LIBERIA USING THE CROPWAT 8.0 SOFTWARE

Abstract

Water is the most important factor for agriculture, and with climate change, the need for efficient irrigation water for crops is increasing. Irrigation water supplies are dwindling and shortages have been reported in many parts of the world. To meet basic human needs, the increase in water consumption due to rapid population growth requires the expansion of food production through irrigation and industrial production and as such, this study aims to determine the crop water requirement as well as the irrigation schedule of ten crops; potatoes, bananas, mangos, rice, groundnut, pepper, cabbage, tomato, maize, and vegetables in the Cestos River Basin, Greenville Sinoe County, Republic of Liberia. Calculations of the crop water and irrigation requirements were carried out using CROPWAT version 8.0. The climatic data used for the calculations were obtained from the Climwat 2.0 software from the Greenville meteorological station in Sinoe County. The results of this study show a method of determining the irrigation water requirements of ten selected crops using the CROPWAT 8.0 model and the CLIMWAT 2.0 software, where rainfall was not taken into account, and as such, results showed that the ETO ranges from 3.18mm/day to 4.02mm/day and effective rainfall ranges from 102.4mm to 197.1; mango had the highest crop water requirement of 1228 mm, while vegetable had the lowest crop water requirement of 288.1 mm. The model predicted the daily, decadal, irrigation schedule as well as monthly crop water requirement at different growing stages of the ten selected crops; potatoes, bananas, mangos, rice, groundnut, pepper, cabbage, tomato, maize, and vegetables in the Cestos River Basin. For the 10 chosen crops at different growth phases, the application of scientific methodologies like CROPWAT and CLIMWAT can reliably determine the crop water requirements and provide irrigation plans and monthly crop water requirements that farmers can accept. In order to save water and meet crop water requirements, farmers can use the study's findings as a guide when deciding how frequently and how much to irrigate the crops that are the subject of the study. Water resource planners can also use these findings when making future plans.