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This study clarified the spatio-temporal structure of the buildings in Sapporo City and the reconcentration of dwelling space in the central area. The data for analysis was the gross floor area ratio and the data sources were the basic survey data for city planning of Sapporo City in 1980, 1986, 1991, 1996 and 2001. First, this research applied the quasi three-mode factor analysis to the three-dimensional matrix ( 3,934 districts, 14 building uses, 5 years ), and considered the spatio-temporal structure of the buildings in Sapporo City. Next, this research analyzed the location of houses, apartments, and commercial establishments by the direction from the central area, and the accessibility to railroad and subway stations. The main results were as follows. As for the spatio-temporal structure of buildings in Sapporo City, commercial establishments excel in the central area, and houses and apartment houses occupy most of the surrounding area. The density of buildings was greater along the subway line. Apartment houses increased in density as opposed to commercial establishments or houses near the stations around the central area. It is thought that reconcentration of this dwelling space in the central area was a phenomenon seen through the period for this research, and accelerated from the second half of the 1990s. Moreover, GIS was useful in the creation of the map data that have a new boundary line, as well as in the calculation of the attribute data accompanying the boundary changes in the analyses.

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The purpose of this study is to analyze and evaluate the landslide susceptibility at catchment scale in the Akaishi Mountains using Decision tree technique which is a kind of data mining techniques. Estimation processes are explicitly and quantitatively represented by tree-structures of Decision tree technique, therefore, tree-structures of the Decision tree model were also analyzed.
To analyze the landslide susceptibility, topographic characteristics (elevation, slope angle, profile curvature, plan curvature, dissection and undissection height) and lithology were used as explanatory variables. These topographic characteristics were calculated from the DEM (Digital Elevation Model). Objective variable was landslides data which occurred or enlarged from 1992 to 2002 as depicted by satellite image analysis. Landslide susceptibility was examined from the ensemble learning using Decision tree technique. In order to evaluate the landslide susceptibility, landslides data which occurred or enlarged from 2002 to 2004 was used.
Accuracy of landslide susceptibility detected by Decision tree technique is as large as 82.4%. This estimation is accurate enough in comparison with previous studies. Namely, Decision tree technique can analyze the landslide susceptibility with high accuracy. Landslide susceptibility was evaluated using landslides data which occurred or enlarged from 2002 to 2004. It was clarified that from 2002 to 2004, landslides tend to occur or enlarge in the catchments which have high landslide susceptibility. Consequently, landslide susceptibility in this study demonstrates the occurrence or enlargement of landslides in the Akaishi Mountains.
Tree-structures indicate that landslides occurred or enlarged frequently in the catchments which have larger than 29 degrees and 33 degrees in average and mode of slope angle, respectively. This result well agrees with previous studies, and, tree-structures of Decision tree indicate important explanatory variables at the higher order in the tree-structure. In conclusion, this study indicates the quantitative relationship between occurrence of landslides, topography and lithology.

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In order to understand the geomorphological features of the slope failures triggered by the Noto Hanto and the Niigataken Chuetsu-oki Earthquakes in 2007, gradient, curvature and aspect of each slope on which slope failure occured were calculated from digital elevation model, and analyzed statistically. It was clarified that the frequencies of slope failures for the steep and convex slopes are relatively high. As for the slope aspect, there exists the tendency of concentration into a particular direction. Results of the analysis of crustal deformation data of GPS continuous stations suggests that the direction of the displacement of ground surface may control such anisotropy of slope failures.

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Arunachal Pradesh (Assam Himalaya) is near Bhutan and Tibet and is composed of 22-24 ethnic groups (51 groups in detail). As the foreigner has been forbidden to enter the area for long time from the border dispute of India and China, it has been veiled in mystery. The foreigner is allowed to stay in the area for only ten days by the permission now. I particularly report nature and human activity in Dirang Dzong area.
1. Topography and land use: Almost residences and cultivated lands are located on the landslide slope and talus slope. Their landforms work in favor for the location of both residences and cultivated lands from shape of landform and sediment.
2. Use of forest: As only fallen leaves are used as manure in cultivated lands, the fallen leaves are the important property of people. The forest is classified into the Conservation area and Non-conservation area and the use of trees vary from area to area. The proprietary rights of fallen leaves are different in inhabitants.
3. Agriculture: Cultivated land is distributed below 2400m (rice field is below 1700m) in altitude and grazing land of yak is above 2000m. The grazing land is formed by the artificial tree death using the poison. The butter and cheese of yak is important income for people.
4. Period inhabited and cultivated by people: It is considered that people have settled since 2000 years ago and intensively done slash-and burn farming since 500 years ago in Ziro area, from the ¹⁴C date of buried humus. In Dirang Dzong area, the date of tree buried in rice field is estimated at 1957-1961 from ¹⁴C concentration. I will examine the period of cultivating in this area from even more humus and tree buried in the soil.

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Mount Fuji is a relatively new mauntain which erupted intermittently until 1707. The tree limit on Mount Fuji is composed of larches (Larix leptolepis). The limit ranges from 1400 to 2900 meters, depending on the slopes. Around Oniwa on the northwestern slope of Mount Fuji, a larch scrub community is scattered in patches, forming an island, where the tree line is 2,700 meters altitude. All of larches are severely deformed toward the northeast causing by strong wind. In this report, the keeping factor of the larch scrub community is examined referring tree size and tree age.
The tree size shortens rapidly crossing the altitude of 2390 meters on the northwestern slope, where is the forest limit. On this slope, we can observe both a group of trees showing s stronger tendency toward the growth in elongation and another group in thickness. These growth patterns change depending on altitudes, namely the higher the altitude, the greater the thickening growth, and the lower the altitude, the greater the elongation growth. On the other hand, the relationships between tree size and tree age show a tendency, in the lower altitude part the older the greater elongation growth, in the higher part the older the greater thickening growth not elongation one. These facts suggest that a larch scrub community is formed controlling by the length of exposure to the severe environment. This also matches that the older the greater deformation.
It's considered that the embolism is a plausible cause for controlling tree size, especially tree height, since frost action, severe transpiration should frequently occur on this slope. As a result, a scrub formation would be fixed. We would like to discuss on a tree form controlled by aging.

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1.Introduction
The amount of surface runoff is influenced by land use and land cover, especially in forested areas. Shi et al. (2007) also pointed out that human activities, land use changes, and urban growth affect runoff characteristics. Mohd &Mansorr (1999) used data from the Landsat Thematic Mapper (TM) to map predicted flood areas and determine the amount of runoff of each sub watershed for the Klang Valley in Malaysia. The SCS TR55 model has been widely used but not for watershed management in Myanmar. We applied the model using the curve number method to estimate surface runoff of the Bago watershed. In the past decade, the Bago River basin has experienced rapid changes in land cover. The main purpose of our study is clarification for the surface runoff characteristics based on land cover change analysis.

2.Methodology
Landsat5 of 1990 and the landsat 7ETM+(2000) was used for surface runoff for the same period was simulated using the U.S. SCS TR55 Model.
The SCS TR55 model can be represented as
Q=(P-0.2S)2/P-0.8S P>0.2S (1)
Q=0 if P<0.2S
Q is runoff (m³/s), P is the amount of rainfall (mm), and S is the potential maximum retention after runoff begins. The watershed storage, S, and the curve number,CN,are related as follows,
S=25400/CN-254 (2)
When using the SCS TR-55 model, a curve number is assigned to portion of a watershed based on soil type, land use/cover type, hydrological soil classification, and antecedent moisture condition.

3. Results
On the basis of our visual interpretation of the satellite imagery, we classified land use/cover of the study area into six categories: closed forest, open forest, scrub and grass, agriculture, settlement areas and bodies of water. From 1990 to 2000, the percentage of forested area (closed forest) to the total area fell from 35.55% to 9.18%. The percentage of degraded forest area (open forest) to the total area increased from 14.76% and 31.7% over the same time period. Father more we compared maximum flood peak discharge at 1%, 2%, 5% and 50% rainfall probability. Our analysis showed the total surface runoff volume increased from 478.41*10000 m³ in 1990 to 516.25 *10000 m³ in 2000. The study area experiences annual flooding in June, July, and August. The mean monthly rainfall of these three months is 3057 mm, or 61.26% of the yearly total. We calculated the surface runoff volume during June, July, and August of 1990 to be 665.02 * 10000 m³ (63.28% of the total) and that of 2000 to be 628.86 *10000m³ (69.9%). Monthly and total surface runoff volume has gradually increased, and it is directly related to the changing land cover conditions.

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The arsenic distribution in aquifers is mainly restricted within the Holocene alluvial plain, the lowland Terai. Hot spot locates very randomly but probably according to the local geology with the lateral and vertical variability, such as sedimentary facies, remains of former meandering, north-dipping thrusts, and multiple folds.
In order to identify the source of arsenic we investigated water quality and geology in four areas in Nepal, Mountain, Hill, Siwalik, and Terai. The metamorphic rocks of the Himalayas will least contribute arsenic contaminations in Terai because they are crystalline mainly consisting of feldspar, quartz and marble. However, weathered marine sediments with fluvial and fluvio-glacial deposits are identified in Jomsom (Annapurna Mountain area) where arsenic rich minerals including arsenopyrite (FeAsS) and arsenic trioxide (As2O3) are generally considered to have been eroded and transported by Kali Gandaki River. Arsenic bearing minerals were deposited at the specific beds in Terai during early-mid Holocene sea level rise.
Arsenic is mobilized in local groundwater with the alkaline nature and can be easily removed and adsorbed in aquifer sediments influenced by pH and redox conditions and by iron related geochemistry. By our study positive correlations have been confirmed among the total concentrations of boron and Fe with arsenic in the groundwater of Parasi in Terai.

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