Seasonal variations in the surface heat fluxes and the soil water contents for the four soil types were estimated, with the use of a soil model and the routine meteorological data of 30 stations in China. Tables of the annual mean values of the sensible and latent heat fluxes, annual potential evaporations, annual precipitations, and the soil water contents at the depths of 0.66m and 0.26m on December 31 are presented. It is found that the annual amount of evaporation and the soil water content in dry season depend on the annual amount of precipitation. A geographic distribution of the annual means of sensible and latent heat fluxes is shown. The net radiation, which is the sum of these fluxes, is large in southern China and the Tibetan Plateau region. The sensible heat flux dominates and the latent heat flux is extremely small in desert region. In general, the net radiation for a loamy soil is larger than that for a sandy soil.

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In this paper, possibility of dam control system applied to both neural networks and fuzzy set theory for supporting reservoir operation is investigated. The authors put the hydrological information of precipitation and predicted inflow discharge etc., and also the information of the past operated by actual operator, into the dam supporting system. In this system, neural networks are applied to the decision of the operational line of reservoir operation for release discharge from reservoir, constant water level and the storage volume and fuzzy set theory is applied to the decision of the operational volume of reservoir operation for the release discharge from dam reservoir. As the result compared with actual operator's operation, it is indicated that dam supporting system using both neural network and fuzzy system is able to apply to the operation for flood control

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In order to clarify the effect of soil pore radius distribution g(r) on the water movement in soil profile, one-dimensional vertical flow equation was solved by using the model for soil hydraulic properties which was derived by applying lognormal distribution laws to g(r). Results showed that the recession hydrograph from a soil profile becomes gradual as the median of g (r) increases. For soil with a relatively large median of g (r), the recession hydrograph becomes steep as the width of g (r) increases. When the median of g(r) is relatively small, the hydrograph has more gradual decreases in recession flow as the width of g(r) increases. This critical median value increases as the length of soil profile (L) becomes small. By comparing pore radius distributions of various soils, it was shown that the undisturbed forest soils yield greater amount of recession flow than the disturbed loamy soils. 70 percent of the disturbed sandy soils yield greater amount of recession flow than the forest soils with L of 100cm. When L is 50cm, hydrographs of half of the sandy soils have greater decreases in recession flow than those of the forest soils. Hydrographs from the crumb-structure forest soils have more gradual decreases in recession flow than those from the granular-structure forest soils. Recession hydrographs from the massive forest soils are steeper than the those from the crumb and granular-structure soils. As a result, it was indicated that well-developed forest soil is effective as the surface soil to increase baseflow from hillslope.

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The Aswan High Dam is perceived, by public even nowadays, to have induced massive environmental degradation. Such a perception is based on the articles appeared in late 1960's to early 1970's, in which predictions were made about the High Aswan Dam's environmental consequences. Some of these predictions however have proved inaccurate or wrong by comparing what were predicted with what actually happened. The fact that those predictions were based on Environmental Impact Assessment (ETA) methodologies suggests that the ETA methodologies to be applied for construction of a large dam may still have rooms for improvement. The wrong predictions about the consequences of the High Aswan Dam on environment included (i) decrease of fish catch in the Mediterranean coast, (ii) slack in fresh water fishery in the Lake Nasser, (iii) proliferation of schistosomiasis, and (iv) emergence of necessity to apply chemical fertilizers. The causes of wrong or inaccurate predictions were as follows: (i) An environmental indicator obtained shortly before commencement of the project was assumed to be the sole “before project” indicator. (ii) An assumption was made based on a seemingly similar, but in fact limnologically quite different, previous case. (iii) The knowledge, on how the project site used to be in the “before project” period, was either inaccurate or insufficient. (iv) Some phenomena observed in the “after project” period were wrongly assumed as the consequences of the project.

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WEFAX is the image signal transmitted from the Geostationary Meteorological Satellite (GMS). There are some commercially available programs to receive the signals and process them by means of the personal computers. All of the available programs are of almost similar level of working facilities for image preparation of specific hours, preparation of animated images from a series of images, detection of cloud top temperature, etc. As GMS is launched by Japan, it has been widely used in Japan for various purposes. On the other hand, some problems may arise if you make use of it for other countries. For example, the images of dislocated areas are deformed due to the earth curvature, which creates misinterpretation of clouds for those regions. The second difficulty is that the image data are overlapped by the latitudinal, longitudinal, and coastal lines, which may lead to erroneous result for digital data analyses. In order to improve these points, a series of new software is developed.

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It is awared that decreasing precipitation of recent years has propelled a declining safety of water in urban areas. As a countermeasure, efforts are focused on expanding the use of existing water resources, and refining sea water for general use. In order to execute these policies, it is necessary to evaluate quantitatively the safety aspects maintained at each local government concerned with water management, in assessing the drought scenario. In this article, for evaluating the water system safety, reliability, resiliency, vulnerability, and also additional DRI (Drought Risk Index) are defined. Further, ACity, as our hypothetical study area, is examined for the effects of remedial policies for drought in the surrounding local governments during those droughts in years 1992 and 1994.

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