Sustainability of irrigated agriculture in Keta district, Ghana

Irrigated agriculture is one of the main economic activities in the Keta district both as source of employment and means of income. The district is very well known for its vegetable production especially shallot. The coastal areas of Ghana including Keta are generally characterized by low rainfall and high evapotranspiration. In most cases, the amount of rainfall is not sufficient to meet the wafer requirement of crops. To meet water deficiency, farmers in the district have a good experience of adopting irrigated agriculture. Farmers use hand-dug shallow wells as source of water and buckets to distribute the water on the fields. This source of water which is basically ground water, is very much susceptible to salt water intrusion, because the agricultural land in Keta is sandwiched between the sea and the greater Keta lagoon which are both salty in nature. The ground water quality in the district is influenced by the sea and the lagoon because of the district’s low altitude. In some places it is around one meter deep and in others even flows freely on the surface. These are typical hydromorphic soils and wetlands along the coast. Various irrigation and water related studies in the region have clearly indicated that irrigation in such environment will highly enhance the upward movement of soluble salts which will move ultimately to the surface and thereby hamper plant growth. Farmers in the district try to suppress the effects of salinity by importing fresh soil from long distance and organic manure like animal dung and plant residues, which increases their production cost. A close observation of this practice will show that this is not long-lasting solution, rather the problem continues year after year with possible increase in salinity. The cumulative effect of the above problems can be summarized as - 1. The agricultural soil in the district is getting damaged gradually a l 7t may reach the level of total toxicity to produce any food crop in the future. 2. The attempt of farmers to overcome the problem has resulted in increasing their cost of production. The economic return from irrigated agriculture is therefore less attractive. In addition to these marketing problem, lack of credit facility and low extension coverage has led the farmers to relay totally on one crop, that is shallot. Irrigation is not a new activity in Keta at all. The people in the district have been practising it for quite a long time. The only change now is that, in former times they were growing plants like coconut trees which have a natural tolerance to salinity, but nowadays because of plant diseases, farmers have changed to shallots and other vegetables. Unfortunately, these vegetables have little tolerance to salinity problems. The general situation in the district indicates that irrigated agriculture is going to remain the main economic activity for the foreseeable future. Some of the problems are built-in by their nature which comes from the practice of irrigation in low land areas. Others can be mitigated by comprehensive irrigation planning approach. Improving the present irrigation practice, diversifying production, extension support and irrigation water with low salt level are some of the measures. These are short term solution& long lasting solutions can be found by approaching the problem from different angles and by trying to incorporate the interest of different groups which have multiple objectives. These can help tremendously in maintaining the benefits from the practice without permanently damaging the natural resource base, with moderate return.

Source: KNUST