Vegetation Mapping of Kushiro Wetland in Northeast Hokkaido, Japan: Application of SPOT images, Aerial Balloon Photographs and airborne color near infrared ( CNIR ) Images for classification Airborne CNIR video images clustered The CNIR video images were clustered (ISODATA) by using aerial balloon mosaicked photo as the training data. Figure 6 shows the clustered image taken from Nadir angle. On the supervised classification, the training area in the video image could be chosen as pure pixels according to the photo manual interpretation. Akanuma marsh vegetation was classified into the following 13 community types; 3 types in the low-moor ; (1). Aquihebosa plants, (2). Alunus japonica, Alunus japonica - Phragmites communis, Alunus japonica - Carex.spp, Alunus japonica - Carex.spp - Phragmites communis, (3). Carex.spp - Phragmites, 4 types in the transitional-moor ; (1). Myrica gale var. tomentosa, (2). Myrica gale var. tomentosa-perennial plant, (3). Carex.spp-prennial plant (4). Carex, 6 types in the high-moor; (1). Sphagnum bog, (2). Sphagnum bog - small shrub, (3) Sphagnum-perennial herb, (4). Sphagnum bog - alpine plant - monocots grass, (5). Sphagnum bog - alpine plant (6). dwarf shrub - alpine plant. Although the coverage size of the aerial mosaicked photo is smaller than the airborne CNIR video image, we could identify the typical communities. Compared to the results of vegetation base map, we could not directly identify the component of sub species in the video image taken from Nadir angle. (such as Sphagnum dominated species in high moor and Myrica gale var. tomentosa in the transitional moor.) While monocots (hard) grass were easily identified into the species level as well as the base map.
SPOT images As for the supervised classification of SPOT images ( Figure 7), the phenology of Carex spp mixed shrub was clearly detected than Chamedaphne calyculata Moench or Alunus japonica. These results are important because this level of detailed classification up to the species level and categories could not be retrieved without utilizations of balloons. Since this classification up to species level could not be identified from any of the satellite image data sets directly for small-scale studies. By using balloon as the platform, it was possible for us to take aerial photographs whenever we want to conduct the experiment. We could monitor the change of phenology and the status of the condition among the vegetation of green grasses and sedge. It was certain that balloon technique helped us provide the additional information of analyzing the SPOT images. The utilization of balloons as the platform of monitoring the terrestrial material is one of the basic techniques in the remote sensing methods. However, it is one of a most effective technique to get the reliable information of vegetation for detailed classification. The availability of these kinds of mapping, as the status of vegetation and the detailed community types will be indispensable and feasible to the conservation for such as biodiversity and spatial heterogeneity. Since wetlands come under the pressure of human activity, it will help us apply to the observation of disturbance dynamics, restoration and invasive species.  Figure 7. Supervised classification of Spot 2 (HRV) images. The training map composed by the mosaicked photo was used for the classification. Images were aquired on 10 June 1998 and 17 June 2000. References
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