[in Japanese]

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This paper addresses the estimation method of discharge for tidal river. Water level in the tidal river is greatly changed in response to the influence of a tide. Thus, the river flow near estuary is characterized by a density current. Consequently, the existing H-Q rating curve gives a large error to estimate the discharge. In this research, time-series of discharge has been observed by using the Acoustic Doppler Current Profiler (ADCP) to improve the discharge estimation. We proposed the new estimation method of discharge based on the analysis of measured flow velocity and water level variation, instead of the H-Q rating curve method.

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We have been developed a Database for Iseri River. This database is made by using Macromedia Flash which is easy to see pictures on the web pages and it is possible to animate some explanations.In this study, the video of harvest mouse is add and possible to see this video for animals in Iseri river catchment.

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[in Japanese]

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The Barato River in northern Sapporo was formed when a meander of the Ishikari River was cut off in the early Showa Era (1933). Eutrophication as evidenced by water bloom results from the hydraulic stagnancy and inflow load from the surround area.In this study, we developed a water quality model toward understanding the water quality formation factors. Flows were calculated using a one-dimensional unsteady flow model. Because the Barato River is situated in a backwater section of Ishikari River, it has a complicated hydraulic structure in which flow direction changes repeatedly. Water quality was simulated by applying the ecosystem model. By taking into account the chlorophyll-a concentration resulting from diatom, green algae and cyanobacteria separately and the nutrient supply from the bottom, water quality related to eutrophication was properly estimated for the long term.

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[in Japanese]

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LTFHR has set up an observation system at three experimental forests in Japan. The observation system sends the data in comma separated text (CSV) format to a remote server via e-mail every day through a cellular phone. All the data sent to the remote server are archived on XML database and published through the web. This web site is made by rich Internet application. The client is derived by Macromedia Flash plug-in on the web browser and the server has a combination of the Servlet on Jetty web container and the eXist XML database. Jetty and eXist are the open source programs.Currently, these data are viewable on-line in the form of tablesand charts in PNG format on the Macromedia Flash player.

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In this study, we carried out a simulation of a heat thunderstorm within the Lake Biwa Basin during the intensified observation period of the Lake Biwa Project 2001 and compared the simulation results with various meteorological observation data. It was found that both atmospheric environment and local circulation, which is strongly affected by land surface processes, are important for prediction of such heat thunderstorms. Therefore, it is indicated that improvement of the land surface processes can be a effective solution in order to improve the prediction accuracy of heat thunderstorms.

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This study shows that the distributed model of permeabilities in geostatistics is proposed and uniquely solved in the numerical test. A hypothetical aquifer divided into twenty piecewise zones is designed. Twenty permeabilities are individually identified with inaccuracy. The exact distribution can be mapped from geostatistical model using accurately estimated parameters. A sensitive range of improvements in such parameters is assessed through water levels and seen over the whole area. It can be proven that the proposed approach is greatly helpful in describing a permeability distribution.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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