An efficient well is essential to arrange a pumping test for aquifer's hydraulic properties determination or for quick water withdrawal purpose. A step-drawdown pumping test is needed to determine the aquifer formation loss coefficient B_f, the entry loss coefficient C_f and the turbulence coefficient n through which well efficiency is determined using the Jacob's equation. As the relationship is non-linear, generally its solution is obtained by the graphic, simultaneous equations solving or one dimensional optimization methods. But all of these methods have some disadvantages. Therefore, the genetic algorithm (GA) is employed to estimate these parameters and thereafter to determine the efficiency of a tubewell located in Tangail district, Bangladesh. Results show that there is a good agreement between the simultaneous equations solving method and GA. Moreover, GA has minimum sum of square of errors value and sum of absolute deviations value with unique solution. But the results by the graphic method differ significantly from those by both of these methods. Therefore, GA could be considered as an efficient technique for Jacob's parameters estimation and well efficiency determination. An inverse methodology of well efficiency determination for same design capacity wells running in the same aquifer is also proposed.

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Precipitation as a key factor for rainwater utilization has been conventionally analyzed paying attention to its quantity. Even though the total amount of annual precipitation is the same, one district might have the concentrated rainfall during a short period, and another district might have rainfall constantly throughout a year. For successful use of rainwater, therefore, it is an essential need to investigate time-varying precipitation from both quantity and uncertainty aspects of rainfall events. Use of the concept of entropy in the realm of information theory is made to evaluate rainfall patterns in terms of rainfall uncertainty. An illustrative entropy evaluation is made to know spatial distributions of the rainfall entropy (with a trade-off relation to the uncertainty) over the whole country of Japan, using the 22-year daily precipitation data recorded at 1,105 observatories of the AMeDAS. The results show that the entropy indeed provides a means of comparatively evaluating local rainfall characteristics on a probability basis, possibly being an alternative measure of regional water resources potential.

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Annually, the salt content (Electric conductivity ; EC) of the stem flow water, the crown drip water, and the rain water show two peaks in Okinawa ; one is in September, the typhoon season in summer, and the other is in November, the monsoon season in winter. The highest values of EC of the stem flow water and the crown drip water are those for the trees grown along the seaside. Especially in the typhoon season EC becomes markedly high. In general EC of the stem flow water is about1.38 times higher than that of the crown drip water. EC of the stem flow water is about 9.00 times higher than that of the rain water, and that of the crown drip water is about 5.70 times greater than that of the rain water.

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Hourly samples during rainfall events were collected at survey points A and B, on mountainous watersheds unaffected by a forest road, and C, affected by the forest road, in order to examine the effect of forest road construction on water quality in a stream. The constituents analyzed are cations Na^+, K^+, Mg^<2+>, Ca^<2+> and anions SO_4^<2->, NO_3^-, Cl^-, F^-. The relationship between the ion concentration and rainfall is affected more by the interval of an antecedent rain event than rainfall. Anions increase more than cations. This is remarkable at the survey point C, which is affected by the forest road. In the relationship between the ion concentration and discharge, Ca^<2+>, Mg^<2+>, Na^+, K^+, Cl^-, SO_4^<2-> and F^- concentrations decrease with an increase of discharge, however the NO_3^- concentration shows an opposite trend. At each of the survey points, most ion concentrations fall in the order of A>C>B but NO_3^- concentration shows the order of B>C>A. Cl^-, SO_4^<2-> and F^- concentrations, when affected by an interval of an antecedent rain event, appear higher at the survey point C than at the survey points A and B. The SO_4^<2-> concentration, mainly originating from the geological material, is regarded as an index expressing the effect of the forest road construction.

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Farmer-managed irrigation systems (FMIS) have contributed greatly to agricultural production in Nepal. An attempt has been made in this paper to discuss the nature and characteristic features of these systems so as to understand their organizational/institutional aspects. Studies show that FMIS operates better than government-managed irrigation systems (GMIS). However these systems are facing problems and the government has duly recognized the importance of assisting them. It is argued that there should be an effective mechanism to provide agricultural support services to the FMIS and to monitor the assistance efforts by the government and the nongovernmental organizations so that the farmers can operate in a better way towards increasing national agricultural nroduction.

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The amount, pH, EC and anions of stemflow in Pinus koraiensis and Larix leptolepis are surveyed and analyzed in order to examine the relationships between watershed conservation function and flood control function of forest in quality and quantity in the Experiment Forests, College of Forest Sciences, Kangwon National University in Korea. Amount and flow rate of stemflow in P. koraiensis have high correlation with rainfall. The pH values of stemflow are much lower than those of rainfall, and EC values of stemflow and throughfall are much higher than those of rainfall. The pH and EC values of throughfall and stemflow are not different between tree species. However, the pH and EC values of rainfall have some influence on those of stemflow. Cl^-, NO_3^- and SO_4^<2-> concentrations of rainfall and throughfall are from 1 to 5ppm, PO_4^<2-> concentrations show 0.57ppm and 0.23ppm in rainfall, 0.12ppm in L. leptolepis. Also, Cl^-, NO_3^- and SO_4^<2-> concentrations of stemflow are relatively higher than those of rainfall, and show differences among seasons. Because these variations indicate that nutrients accumulate in the phloem and that dry depositions of stem or crown are leached and washed off, further study is required to investigate the damaged structure and buffering capacity of trees to acid rain, in order to suggest some strategies for methods of forest reforestation and hydrologic maintenance.

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In order to numerically evaluate the water discharge property of the two watersheds in the Ookura River located at the Sado Island, we apply the Hydrologic cycle model (HYCYMODEL) to the discharge response to rainfall observed in the forest catchment and the grass catchment. The parameters in this model are optimized by the trial and error method. Adaptability of the HYCYMODEL to observed discharge is fairly good for 6 years in the snowless periods. The ratio of infiltrating area to total catchment area and baseflow discharge are large in the forest catchment. So, the water storage capacity in the forest catchment is large compared with that of the grass catchment.

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Recently in the urban area such as Tokyo, people suffer from water shortage while heavy rains cause flooding. It is because of both facts that city water supply is depend on the source far from urban area and that rainwater can not penetrate underground so that most of ground surface has been paved with asphalt. One of the solutions to this problem is the rainwater catchment system such as rainwater storage or rainwater-permeation facilities. Although they have been popularized gradually in Japan, mainly large scale ones have been installed school buildings and public ones, etc. It is clear that their effect becomes even stronger as the rainwater catchment systems installed increase. For more increase in them, it is necessary that the rainwater catchment system will be widely used by an individual. Some local governments have built financial support systems that help an individual install his house. In this paper, the existing state of financial support systems on WWW that differ from each local government is investigated.

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The effective utilization of rainwater and the jointed solar movie source attract much attention nowadays. Especially the sustainable and clean characters of these energy and resources are estimated much with the hope of the decrease of the power plant cost. This paper investigate the independent plant grow system with these resources and energy. The system supplies and maintains the effective Dissolved Oxygen in the water tank of mini-tomato water cultivation system and tube irrigation system by solar power of Direct Current and an aeration blower system. The solar cell-set has 4 sheets and each sheet has the ability of 48 W of power plant. The dimension of this water cultivation has 3 places and each size is 90cm × 90cm. The valve is automatically operated by timer so that 3 l /min of water is supplied for 10 minutes in an hour. And solar pump raise up the water from suction sump to discharge one. And aeration blower send oxygen to culture bed through pine in the tank. 1 bed has 3 l /min × 10min=30 l and 1 cycle is 70min, so totally 30 l × 21=630 l is supplied. Considering that the total 3 beds have 630 × 3 beds=1,890 l = 1.89m^3, the scale of suction and discharge sumps is 1.5m × 1.5m × 1.0m=2.25m^3 > 1.89m^3. Considering with the ability of pumping in the most severe conditions as in winter season that has the shortest hours of sunshine as 3 hours, and with the 2 meters of total pump head, the total discharge is 13 l /min, So, the ability is calculated as 13 l /min, ×60min × 3hr=2.34m^3, This shows the sufficient condition for the needed water volume of 1.89m^3. Thus these systems showed much effect that raise up the quality and quantity of grow plant with the sufficient maintenance of DO density for water cultivation.

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A linear control system is developed and is applied to automatic control of reservoir release discharge using precipitation data. A nominal generator, which is an estimated runoff model from precipitation to inflow into the reservoir, is assumed to be obtained. The control system has three controllers to cancel out external disturbances, to handle wind-up phenomena in the release discharge, and to stabilize the entire system under observation errors. Demonstrative calculations are executed using flood data observed at an existing dam. The results show that three controllers mends the variation in the reservoir storage complementing each other.

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Instructions are given to prepare the manuscript of an English paper submitted to the Journal of Rainwater Catchment Systems. Being a model in itself, the document demonstratively prescribes the layout of the manuscript. Manuscripts should be typed on one side of white A4 size paper when they are submitted. Accepted manuscripts will be off-set printed. Titles of papers, names and affiliations of authors, abstracts, main texts, headings, references, equations, mathematical symbols, captions of figures and tables and so on should be in specified fonts. All references cited should be collected together at the end of the paper. Figures and Tables with their captions should be placed appropriately.

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Instructions are given to prepare the manuscript of a Japanese paper submitted to the Journal of Rainwater Catchment Systems. Being a model in itself, the document demonstratively prescribes the layout of the manuscript. Manuscripts should be typed on one side of white A4 size paper when they are submitted. Accepted manuscripts will be off-set printed. Titles of papers, names and affiliations of authors, abstracts, main texts, headings, references, equations, mathematical symbols, captions of figures and tables and so on should be in specified fonts. All references cited should be collected together at the end of the paper. Figures and Tables with their captions should be placed appropriately.

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