|Budget Amount *help
¥1,600,000 (Direct Cost : ¥1,600,000)
Fiscal Year 1996 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1995 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1994 : ¥600,000 (Direct Cost : ¥600,000)
This study was done from 1994 to 1996 to develop the necessary silvicultural technique, forest operation plan and improvement ; and to find out about several fundamental factors of the denuded forests in the South-West islands. The major denuded forest of the South-West islands have small islands of wind-beaten forest lands. In the southern region of Okinawa Island, no these wind-beaten forest land, there are lots of growing areas of Leucaena leucocephala, and Miscanthus sinensis. On the growing areas of L.leucocephala etc., actual on-the-spot issues with respect of silvicultural techniques were surveyed. By using aerial photograph and image processing of LANDSAT-TM data, issues concerned with the denuded forest, forest type classification etc. necessary for forest operation planning were investigated.
(1) In the L.leucocephala forest of the southern region of Okinawa Island, generally tree heights are short, diameter of trees very small, tree density very high and is an uneven-aged pur
e forest. In the L.leucocephala forest, the growth of other tree species is very difficult. Plant heights of M.sinensis are about 4m, growing very large and suppressing other plants. (2) In using LANDSAT-TM data, area classification of small area L.leucocephala forest was done. Accurate classification of small areas less than l ha was difficult. Using Clustering method approximate classification can be done, however erroneous classifications are high. (3) In the classification of L.leucocephala forest and other forest types, the applicability of photo-interpretation and image processing of aerial photograph were investigated. The accuracy of interpretation by the steroscope of aerial photograph is very excellent. However, accuracy with respect to Clustering and supervised classification methods is low. (4) Under the image processing of aerial photographs, in classifying the wind-beaten forest on hillsides, denuded forests of L.leucocephala etc., and other forest types, it is important to investigate factors of topographical features like direction bearing, gradient etc. (5). Using LANDSAT-TM data, area classification of the wind-beaten forest land on about 1,500 ha of the island was done. Based on vegetation index and supervised classification, a practical use of an excellent result can be done. Less