This study was designed to clarify the accuracy of X-band multi-parameter radar (X-MP) over the Hokuriku region using rain gauge data and quantitative precipitation estimation (QPE) by C-band radar. Moreover, this study used results of the correlation coefficient and estimate error for QPE accuracy analysis.
 Temporal analysis revealed that X-MPs provide observation data with high accuracy for short-term downpours, but results for long-term and light rainfall or regions distant from the radar site were less accurate.
 Spatial analysis showed the X-MP data accuracy was observable with sufficient accuracy within a range of 2.25 × 2.25 km as the center of each rain gauge station. The X-MP data accuracy has less than the C-band radar data accuracy beyond a 20 km radius from the radar site.
 Quantitative analysis of the rainy season and snowy season, total precipitation of X-MP and C-band radar were overestimated from that of the rain gauge station, it was especially overestimated significantly during the snowy season.

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 This study was conducted to obtain fundamental information to elucidate the transition of the dominant species from green alga Scenedesmus quadricauda to blue-green alga Microcystis aeruginosa. Monoculture and monoxenic culture experiments for both species were conducted under nitrogen-limited conditions (monoculture, NO₃-N = 0.1-5.0 mg/L; monoxenic culture, NO₃-N = 0.5-5.0 mg/L) with a phosphorus concentration of 1.55 mg/L. Monoculture experiment results demonstrated that the Δ N/ Δ Chl.a value was ca. 5–7 times greater value for M. aeruginosa than for S. quadricauda at NO₃-N = 0.5, 1.0, 2.5, and 5.0 mg/L. These findings imply that S. quadricauda possesses better ability for nitrogen productivity than that of M. aeruginosa. Monoxenic culture experiment results show that M. aeruginosa and S. quadricauda were respectively dominant at NO₃-N = 0.5 mg/L and 1.0-5.0 mg/L. Furthermore, monoxenic culture experiment results suggest that a switching point of the N:P ratio for the dominance of S. quadricauda or M. aeruginosa exists in the range of 0.3 (NO₃-N = 0.5 mg/L) to 0.6 (NO₃-N = 1.0 mg/L).

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 In recent years, heavy rains have often flooded houses. Some measures are necessary to minimize flood damage. One set of measures is to evacuate people from the flooded region, move the houses to non-flooded (safe) areas from flooded (risk) areas, and prevent the construction of any additional houses building in the flooded areas. From this study of the towns of Kanagawa prefecture, we have estimated the likely number of households and population number up to 2050. We have also estimated spatial arrangements and life cycles of the houses. Using these estimates, we have analyzed how much flood damage would be mitigated if houses and people were relocated to safe areas. Results show that if similar floods occurred in 2050, then moving houses and people from risky areas to safe areas would reduce flood damage costs in Kanagawa prefecture as a whole by a maximum of 6,832 billion yen, compared with the scenario of no change in the current business as usual housing placement policy and practice.

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