In recent years, identifying the relationship between spatial pattern and scale has emerged as　a central issue in ecology and geography. Scale has been defined by grain, or resolution here. Bias in the results will occur if the scale is wrongly selected for landscape evaluation. In particular, with remote sensing becoming widespread, monitoring and detection on landscape dynamics from local to global scale has become available, selecting a satellite with appropriate spatial resolution for research objective scale is thus becoming essential. Moreover, it is necessary to understand scaling among different satellite data, which is important for improving the efficiency of remote sensing. In this research, satellite data of various resolution, QuickBird (2.5m), ALOS AVNIR-2 (10m), Terra ASTER (15m) and Landsat ETM+ (30m), were employed to analyze the scale effects of grain size. The research was implemented at Azeta, a typical Yatu landscape located in Sakura City, Chiba prefecture. Land cover classifications were first implemented using the Maximum Likelihood Method on satellite data of various resolution. Based on the results, classification maps from each satellite image were systematically resized from their original pixel size and a series of coarser resolution maps were created through the majority rule. Finally, nine of landscape metrics imbedded in the FRAGSTATS were derived from these aggregated categorical data for landscape pattern analysis. The results indicated that most landscape metrics obviously increased/decreased in scaling relations such as power-law and logarithmic among the satellites having various resolutions.

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In this study, we evaluated the pattern of agricultural landscape mosaic in Niigata Prefecture using the Satoyama Index (SI), which is a simple index composed by agricultural landscape heterogeneity and the ratio of nonagricultural land cover. At first, land cover map based on LANDSAT imagery was classified by supervised classification method. Next, we calculated landscape heterogeneity among the 400 grid cells (20 × 20 grid cells: 600m×600m) comprising each agricultural landscape unit from the agricultural landscape heterogeneity index (ALHI). We obtained index values by multiplying the ALHI by the proportion of grid cells classified as nonagricultural landscape elements without urban within the basic landscape spatial unit. SI value was high in the bordering area between slope and flat area such as edge zone of forested area and agricultural lands. In addition, SI value was high also in the portions of along the main river or the coastal forests. There was no inconsistency in the number of landscape elements and SI value within the spatial unit by comparing the spatial pattern of land cover and the SI value. Since SI evaluates the heterogeneity in the agricultural landscape, SI showed zero in the homogenized area such as the broad-leaved deciduous forests. From our results, we pointed out that SI can just quantify the degree of heterogeneity of agricultural landscape, and it is inappropriate to evaluate the biodiversity in a region only with SI value.

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To assess the feeding site utilization by duck species in the Nomigawa River, a typical urban river in Tokyo, we conducted 32 line-transect surveys during Dec. 2008 - Apr. 2010. We also collected benthic invertebrates and grass seed samples at 11 study sites in Feb. 2010. The grass seeds was most abundant at the shallow riffle connecting to the inlet of a large pool. Meanwhile, chironomid larvae and pupae were most abundant at the shallow riffle below the outlet of a large pool. The dominant species of ducks were Anas poecilorhyncha, A. acuta and A. crecca. Main feeding sites of these three duck species were shallow riffles, but A. poecilorhyncha and A. crecca were densely congregated at the shallow riffle below the outlet of a large pool, whereas A. acuta densely congregated at the shallow riffle connecting to the inlet of a large pool. Therefore, it was supposed that the bate selectivity differs between these two groups of ducks. We suggest that the physical complexity of stream environment caused by presence or absence of artificial groundsill supports the complexity of species composition and the high density of ducks.

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Relationship between bank vegetation and environmental factors were investigated in lower reach of Chino River, Kushima, southern Kyushu in order to provide basic information for restoration of natural vegetation after river construction work. Plant species composition of 37 quadrats placed on different physiognomy and topography were classified into four vegetation types by TWINSPAN. Close relationship between the four vegetation types and physical environments were detected by ANOVA, indicating a certain level of vegetation differentiation according to their site condition within a river bank. However, comparison with the natural vegetation along the similar river reported in the previous studies suggested that the vegetation of the studied reach was not fully differentiated due to the lack of intermediate conditions of micro-topography and soil moisture between dry sites on upper banks and wet sites on riverbed sediments. Among the studied site, concave slopes on the bank showed the intermediate soil condition in terms of soil hardiness and EC. We concluded that the studied vegetation of the Chino River had less diverse structure compared to the natural vegetation. We suggest that the restoration of current vegetation structure after river construction is minimum requirement, and that formation of the intermediate site condition such as concave bank slopes are desired to enrich the restored vegetation on the new channel bank.

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This research focused on topography and land ownership, and clarified changes in landscape structure and the factors that had brought about these changes. Aerial photographs and historic maps from six different dates, covering a 125 year period from 1882 to 2008, were analyzed. The landscape structure was mapped in terms of 15 different landscape element types. The target area was divided into three topographic categories, valley (lowland), slope and upland, using 5 meter mesh elevation data, and land ownership was mapped based on data provided by Sakura municipality. Changes in landscape structure were analyzed according to topography and land ownership. The results showed that on the valley floors many rice paddies were abandoned, starting during the 1970s. Other paddies were consolidated and fitted with underground drainage systems. On top of the uplands, forest landscape elements, which originally accounted for 71% of the area, decreased to 43% by 2008. In contrast, forest landscape elements on the slopes remained at 70% over the period covered by the research. More specifically, Pinus densiflora plantations, which once covered most of the uplands and slopes, disappeared totally by the 1990s, due to pine wilt disease. Cryptomeria japonica plantations also decreased from the 1980s onwards. This decrease in conifer plantations was accompanied by a corresponding increase in secondary deciduous woodland. The results also showed that ownership patterns influenced the timing of rice paddies abandonment.

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