GIS-理論と応用
Online ISSN : 2185-5633
Print ISSN : 1340-5381
ISSN-L : 1340-5381
17 巻 , 2 号
選択された号の論文の7件中1~7を表示しています
ソフトウェア論文
原著論文
  • 吉川 沙耶花, カザディ サンガ ンゴイ
    2009 年 17 巻 2 号 p. 145-154
    発行日: 2009/12/31
    公開日: 2019/04/11
    ジャーナル フリー

    Vegetation cover change has been reported to occur over large areas in Mato Grosso, the central-western Brazil state known to have the highest deforestation rate. 5-year Digital Vegetation Model (DVM) Maps for the 1981-2001 period were created using the first components of the principal components analysis(PCA) of monthly NOAA/AVHRR multispectral data(Channels 1, 2 and 4). From these 5-year DVM vegetation change maps were obtained. Three main types of vegetation changes are identified: Degradation, Recovery and Transitional states. Vegetation and land cover changes are characterized by deforestation of tropical rainforests in the north and large-scale savannization expanding from the south. Change rates are shown to be larger over non-inhabited areas (56%) and far away from the main highways(52%), than over the populated zones in the south(42%), or within 50km of the roads (44%). These findings point not only to the role of population density and road building in accelerating deforestation, but also to that of navigable rivers, especially over the roadless north. In total, degraded and transitional areas had expanded over 53% of MT between 1981 and 2001, in relation to increasing cattle ranching and soybean production in this state. All these findings highlight the non-sustainable processes of resource development occurring in Brazil and especially in Mato Grosso.

  • 比留間 祐太, 齋藤 仁, 中山 大地, 泉 岳樹, 松山 洋
    2009 年 17 巻 2 号 p. 155-165
    発行日: 2009/12/31
    公開日: 2019/04/11
    ジャーナル フリー

    Previous studies pointed out that the distribution of Abies mariesii is determined by snow pressure, strong wind, topography, and so on. However, the ranking of the factors based on their importance has not been assessed quantitatively. Using a statistical decision-tree model, this study ranked the factors (Warmth Index, snow depth, elevation, slope, aspect, and snow pressure) around the Joetsu mountains. We found that more important factors were (1) Warmth Index, (2) snow depth, and (3) slope, or (1) Warmth Index, (2)snow depth, and (3) Warmth Index in the order of importance. The former well explained the distribution of Abies mariesii around Okushiga region, while the latter with elevation well explained the distribution around Mt. Naeba. Some of these factors are likely affected by the global warming, thus, this paper also discussed that the distribution of Abies mariesii may considerably change under the climate in future.

  • 竹添 勝俊, 龍原 哲
    2009 年 17 巻 2 号 p. 167-177
    発行日: 2009/12/31
    公開日: 2019/04/11
    ジャーナル フリー

    We predicted the dominance of planted and invading trees using the site index and site index curves. The study area was Compartment No. 25 in the University of Tokyo Forest in Chichibu, Japan. Sixty 10×10 m plots were established in a plantation of hinoki cypress (Chamaecyparis obtusa). Six factors were calculated from a digital elevation model (DEM): altitude, slope angle, flow accumulation, the wetness index, shaded relief, and curvature. The maximum heights of hinoki cypress and invading hardwood trees were classified as explanatory variables by regression trees with these factors. The Richards function was fitted to the tree height growth of them from the tree analysis data. The site index curves for them were drawn for the values of the site index classified from the regression trees, setting the tree height growth curve expressed by the Richards function as a guide curve. Comparing all combinations of the site index curves for them, we showed how many years after invasion hardwood trees take to exceed the height of hinoki cypress.

  • 熊谷 樹一郎, 何 勇, 伊勢木 祥男
    2009 年 17 巻 2 号 p. 179-190
    発行日: 2009/12/31
    公開日: 2019/04/11
    ジャーナル フリー

    In this study, we developed the analysis method of vegetation distributions in terms of prevention of the fire spreading through applying a fire-spreading model. With the fire-spreading model, we analyzed the spatial relationship between vegetation distributions and buildings in the two cases: one meant ordinary situation, the other meant current vegetation distribution was removed hypothetically. The difference between the numbers of buildings burnt in the two cases was defined as the vegetation role in preventing the fire spreading. As a result, it was shown that the differences might be the spatial information that could be useful for the estimation of the vegetation role in terms of prevention of the fire spreading. Through the comparison between the analysis result and the result of field survey, the proposed method seemed to be valid for evaluation of vegetation functions for prevention of the fire spreading in an urban area.

  • 山田 博幸, 古戸 孝, 角本 繁, 小杉 幸夫
    2009 年 17 巻 2 号 p. 191-201
    発行日: 2009/12/31
    公開日: 2019/04/11
    ジャーナル フリー

    This study proposes to improve the efficiency of victim support services based on construction of ad hoc information environment by using spatial-temporal GIS which achieves the information support to the disaster affected municipality. Cooperation with conventional back office system data can be integrated in this system environment and framework. The proposed information environment was implemented to the affected municipality in the Niigataken Chuetsu earthquake area, and the effectiveness was verified in this study. Contribution to improve the efficiency of victim support services was accepted by the municipality official, and an ad hoc system has been changed from supporting person's tool to municipality official's tool. It is clarified that the implemented ad hoc system based on dynamic topology calculation and the spacial temporal data base contributes to improve the efficiency of victim support services in the municipality of the conventional system environment.

研究・技術ノート
  • 島川 陽一, 鹿島 茂
    2009 年 17 巻 2 号 p. 203-209
    発行日: 2009/12/31
    公開日: 2019/04/11
    ジャーナル フリー

    Although digital spatial statistics and map are becoming available recently, it is insufficient to study the configuration methods of data and parameter for a traffic assignment. In this paper, configuration methods are studied for traffic assignment using a GIS data. In detail, a method constructing road network from digital map and a set up method of a link parameter are studied. Moreover, methods speeding up assignment calculation in term of data configuration are explained. In numerical simulation, the methods are evaluated by assigning traffic in Tokyo metropolitan area and the results are shown in calculation time suitable for practical use and in assignment accuracy.

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