Two Forms of Agricultural Development in Sultanat of Oman

Abstract

Sultanat of Oman located at the south-eastern edge of Arabian Peninsula covers an area of 300, 000 km2.Though almost of the area consists of desert, she has 5, 000 year history of irrigation agriculture by groundwater. Although the country produce oil, Omani people, having been aware of the limitation of the resources, have made efforts to the pervation of education and agricultural development.The country is geographically characterized by the existence of two lines of mountain range. Oman mountain chain extending 600 km long in a direction paralle to the Batinah coast consist of many steep 3, 000 m class high peaks.Dohar mountain chain facing to Arabian sea and extending east-west direction has an altitude of about 1, 000 m. Southern side of the mountain chain shows steep topographic feature of fault scarp. Contrary to the fact, northern side of the mountain ridge show very gentle slope and dips toward the Rube al Khali desert.Although Sultanat of Oman climatically belongs to the tropical dry zone, it rarely severe rains in the steep slope of mountain region caused by the upstream air current. The precipitation is the source of ground water of the country. In the Batinah coastal region, irrigation water have been drawn up by small scale wells and in recent years by deep wells with Submarin pumps.Accompany with the increase of irrigated farm, excessive pumpages have outstripped natural recharge of groundwater resulting in the intrusion of sea water.In order to prevent salinitization of groundwater a number of recharge dams which reserve flood temporary and percolate the water under the gound have been constructed.There are no cultivation in the Nejd region located at the northern gentle slope of Dhar mountain chain, owing to very poor available water resources. Only a few nomads are found here and there near the water shed.In Nejd groundwater was first found out by exploration drilling for oil in 1955. In recent years it has been clarified that plenty of good quality groundwater is confined in Tertially limestone aquifers lie 300-600 m under the ground. Hydrological and hydrogeological conditions show that recharge to the aquifers is small, development would inevitably involove mining of groundwater from aquifer storage.It was decided agricultural development must be carrid out step by step appraising the volume of groundwater resoces. Pilot farm 50 ha in area accompany with 2 production wells and 4 monitoring wells is now under construction in technical cooperation with Japan.