Mapping of mixing ratio of deciduous broadleaves in sugi cedar [Cryptomeria japonica] plantations in a heavy snow area: An analysis using Landsat TM data and forest management information
2005
Awaya, Y.(Forestry and Forest Products Research Inst., Tsukuba, Ibaraki (Japan)) | Nishizono, T.
To understand environmental effects on cedar growth, the ratio of deciduous broadleaves in cedar plantations was analyzed using a simple and generalized method. A forest type map of four forest classes (Evergreen, Mixed-A, Mixed-B, and Deciduous) was created using forest management information in a geographical information system. Topographic effects in two TM images taken in June 1994 and September 1996 were removed using the pattern decomposition method. The surface area in the images was classified by the ISODATA method into 25 categories, which were grouped into 7 classes including the 4 forest classes by reference to the forest type map. A classification map was created by assigning each pixel to either the evergreen or deciduous class. Finally, subcompartments were classified as evergreen, mixed or deciduous classes based on the ratio of deciduous pixels in the sub-compartments. The accuracy index. KHAT, was 0.773. The classification map showed that the ratio of deciduous pixels was higher in forests on steeper slopes, and increased at elevations over 800 m. These results suggest that snow gliding, deep snow and cold air temperature inhibited cedar growth. The resultant map showed the mixing ratio of deciduous trees in cedar plantations, which should be useful for forest management, such as finding suitable areas for cedar plantations.
Показать больше [+] Меньше [-]