3-2. Optimal implementation strategies of rice and vegetable irrigation using small reservoirs in northern Ghana

Small-scale irrigation using rainwater-harvesting reservoirs is effective in enhancing the adaptation of predominantly rainfed and vulnerable production systems to climate change in African drylands. However, the required technological improvement, participatory breakthroughs, farm risk management, and investment justification are rarely established comprehensively and integrated into adaptive planning. This chapter highlights the outputs from Koide et al. (2021), which explored reservoir-based irrigation cropping strategies synthesizing technological, participatory, managerial, and investment capabilities. They crafted an innovative rice and vegetable pond irrigation system as a technological contribution. The system was validated through a five-year participatory on-farm experiment in northern Ghana. Using agronomic, hydrological, and socioeconomic data obtained from the experiments and surveys, they constructed bioeconomic models to identify optimal irrigation cropping strategies that are the most efficient in securing smallholders’ food and income and resilient to interannual climate fluctuations. The net present values were computed to determine the financial effects of the identified strategies on the investment payback of the pond system. The on-farm experiment results indicate that supplementary irrigation increased the average rice yield by 23%, more than doubled the profitability, and lowered the coefficients of its variation compared to rainfed rice (from 48% to 38%). Vegetable irrigation in the dry season was even more profitable. The optimal cropping strategies identified by bioeconomic models mainly combined multiple rainfed crop choices with balanced irrigation allocation between rice and vegetables, enabling food self-sufficiency and increased income level and stability. A pond storage capacity of 5000 m3 was sufficient to secure these benefits under the observed climate fluctuations. The cropping strategy found to produce sufficient financial increments to achieve mid-term (8–12-years) payback of pond investment under the same level of risk that smallholders accepted under rainfed systems is among the most advisable.

言語

内容記述

内容記述タイプ

Other

内容記述

Chapter 3: Issues and model-based optimization of smallholder technology adoption in lowland cropping systems : Case of irrigation technology in northern Ghana

言語

出版者

Japan International Research Center for Agricultural Sciences

言語

eng

資源タイプ

資源タイプ識別子

http://purl.org/coar/resource_type/c_3248

資源タイプ

book part

出版タイプ

VoR

出版タイプResource

http://purl.org/coar/version/c_970fb48d4fbd8a85

ID登録

10.34556/0002000781

ID登録タイプ

JaLC

Versions

Ver.1

2025-04-03 02:23:50.205702

Show All versions

Cite as

エクスポート

OAI-PMH

JPCOAR 2.0
JPCOAR 1.0
DublinCore
DDI

Other Formats

JSON
BIBTEX

インデックスリンク

インデックスツリー

アイテム