However, as predicted by the WEAP analysis, supplemental irrigation in the small-scale scheme could be possible only if the rise in water demand is counterbalanced by about 10% increase in the system efficiency and by setting limits on the cultivation of the water-intensive tomato crop in the dry season.
The unavailability of long-term historical data at present prevents the calibration and validation of the WEAP model in Ghana but the conducted scenario analysis sets the framework for further evaluation of the potential water scarcity adaptation options.
For field-level evaluation, the FAO Aqua Crop model was applied to develop an improved year-round irrigation schedule for dry-season cultivation of tomato and to assess a possibility for supplemental irrigation of maize in the rainy season under “wet” and “dry” climate scenarios.
Finally, a scenario-based analysis of irrigation performance was conducted at scheme scale for the period of 2015–2030 using the Water Evaluation and Planning System (WEAP), a decision support modeling tool.
In particular, the medium-scale irrigation scheme utilized less than 40% of total storage, whereas the small-scale scheme utilized about 70% of the storage.
The examination of field-level water management practices suggests that an application efficiency of 58–68% is achievable in both schemes by improving the irrigation scheduling of the major crops.DART-Europe e-theses portal : DART-Europe is an online portal of dissertations and theses from universities in 19 European countries.Networked Digital Library of Theses and Dissertations (NDLTD) : NDLTD aims to share knowledge worldwide by making international dissertations and theses available electronically.During the Disputation, the candidate is examined on the research presented in the dissertation as well as on other topics important to the candidate’s general field of research.Prerequisite for being accepted as a doctoral student is the completion of one of the following university degrees, with above-average results: , or an equivalent university degree from a German or foreign university in Chinese Studies or a comparable field of studies.Funding needs to be individually obtained by application to any pertaining domestic or international funding body.Dissertations at Heidelberg University may be prepared in either German or English language.Dissertations and theses submitted in partial fulfillment of the requirements for master's or doctoral degrees at the University of Michigan. dissertations at the University of Michigan in Ann Arbor are awarded by the Rackham School of Graduate Studies.This collection also includes theses written by U-M faculty. The entire system of two (a small- and a medium-scale) irrigation schemes shared by multiple users in the Upper East region of Ghana were examined, including the water reservoir, water conveyance and distribution network, cropping fields, and management entity.First, multi-level performance indicators with relevance to water delivery, water utilization, and agricultural production were adapted and applied based on measurements of meteorological, soil and groundwater parameters, irrigation water inputs, crop management and yields for two rainy and dry seasons during 2014–2016 in prevalent cropping systems.