A large-scale landslide occurred in May 2015 in headwaters of Tedori River at the foot of Mt. Hakusan. Highly turbid water has been generated from the landslide, which has had wider and seriously influences on the downstream area by such as rice paddy irrigation systems, ground water system, fresh water and coastal fisheries. Airborne LiDAR data and series of air photos were employed to analyze topographical features, this landslide occurred within the old landslide body. The suspended solids and sediments showed high pH and Ca concentrations, which gave the effects on the early growth stage of rice plant and the uptake of essential microelements. Miyatake settling basin has a role to prevent sediment from flowing into farmlands. Sediment heights of the sand settling channels were measured and the volume of total sediment was estimated, then it was concluded that the settling basin has performed very well. From May 2015 when the high turbid water occurred, the groundwater tables in the alluvial plane began to decrease seriously. So, it has been required to analyze the water balance in the aquifer and evaluate the influence of turbid water. A hydrologic model was developed for the analysis and evaluation. The model performance was very good and it is expected that the model will be available to predict the influence of the turbid water. Since the sharp decline of groundwater level has gave a serious damage to Pungitius sp.1, it is considered that the addition of spring-fed ponds with groundwater lifting pumps is urgently required for the future depletion of spring water.

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There is no agreement among researchers on whether the world population can continue to increase when its effect on the environment is considered. In this paper, I reviewed the views of the neo-Malthusians who are pessimistic about the influences of the population growth on the environment and the revisionists those are optimistic about this problem to find out the reasons and backgrounds for their different positions. The results of the review indicated that the difference between the neo-Malthusians and revisionists is ascribed to the distinctions in their view toward nature. Neo-Malthusians evaluate effects of population increase on the environment from a nature-oriented view such that nature cannot be controlled by humans while revisionists grasp environmental problems related to population increase from a human-oriented view where they believe nature can be ruled by humans.

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We attempt to make an eLearning system for supplementary lesson for Mathematics. In this paper, we analyze the results of the supplementary lessons for mathematics in 2013 and 2014, and discuss usefulness of our eLearning system in the case study of the students who are not good at Mathematics.

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This case study illustrates the political effects of land consolidation acts not only on agricultural workability and efficiency of management but also on residentsʼ relationship. And some important matters became clear through a questionnaire surveys used in the study. Some direct effects on agricultural work and comfort in rural life received a comparatively positive cognition from almost all respondents of this survey. However, consequential social effects for community invigoration were perceived as somewhat negative influences. These results provide important suggestions for the institutional designing of future land consolidation acts.

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