沖縄本島における海岸線利用に関する調査研究

抄録

The coastal zone in Okinawa is rich in natural conditions in comparison with the Seto Inland Sea. However, a serious problem situation is involved in both the present and future use of coastal zone of the Island. It has already come into artificial use by 30% of total length 564 km. Above all, the extinction of natural coast through reclamation amounts to 9.8%. The present situation of coastal zone is in danger of being radically transformed through the development policy of Okinawa, in particular the Ocean Exposition of 1975, together with the U. S. armed forces. In view of these problem situations, the writers have conducted an investigation into the use of coastal zone in Okinawa Island and pointed out some problems at issue. The coastal zone may safely be classified into natural, semi-natural, semi-artificial, and reclamation coast according to its conditions, and again into recreation, harbour, industrial, U. S. armed forces, road, and settled area coast according to its use. Then the degree of nature and closed coast rate may be caluculated. The future use of coastal zone will be basically conditioned through reclamation planning. The reclamation is the most positive type of use among many kinds of coastal zone use. It results in the direct and absolute extinction of natural features around it. So the whole plan and vision of reclamation in the Island will be examined and checked, particularly in the Bay of Kim. The planned area of reclamation is 2,658 ha, and visioned about 7,081 ha. It makes a total of about 9, 739 ha, which are twenty times as large as the existing reclamation area. Their main purposes are for industrial, leisure, harbour, and public facilities. If the plan should be wholly enforced, the ammount of extinction would come to I km of natural, 20km of semi-natural, and 5 km of semi-artificial coast, and the reclamation coast would increase by as many as 43km. The degree of nature would go down from 74.4% to as small as 66.6~~-The sea and coastal zone have been closed by the activities of U. S. armed forces since the end of the Battle in Okinawa. And the rapid closing is accelerated by the industrial activities and enclosure movement of capital, and further by many kinds of pollution near the coastal zone. But it is needed that the coastal zone is opened for every possible activity of local residents. Our task is not in consuming the natural environment (i. e. a coral reef) in a short time, which has been formed for a 10ng time, but in bringing it to life vividly. There is some hope In the future use of the coastal zone in Okinawa Island. In some self-governing bodies, there come out the trends of considering the coastal zone use in essential way, although the problem situation in these bodies may be very acute and difficult to solve. In Okinawa they find it in a rapid industrialization and development of tourist industry to correct the economic difference in quality and to get rid of the economic system conditioned by the U. S. armed forces. Though we do not keep the direct counter proposal in hand, it is possible from the study in the use of coastal zone that it is much dangerous and resultless to correct that difference with Japan proper through introducing capital from Japan.