The zonal travel-cost method was used to value non-market recreation benefits derived by visitors to Jike-Furusatomura village in the northernmost of Yokohama.
A visitation frequency function which explains the number of visitors in each zone and a demand function for the village as a recreational area were estimated, and a result, in terms of consumer surplus, is presented for all informal recreation visitors. The total economic value of recreational benefits was estimated at approximately 80 million yen annually.

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The purpose of this paper is to make clear the various kind of the inhabitant consciousness of the rural community sewerage improvement project which is the kernel of residence environment improvement.
The results assume to fill the important role of the project promotion and the agreement of benefit inhabitant charge to the maintenance of the system. Tohoku-Noushi (TN) method (first step) is available to make clear the various kind of the inhabitant consciousness of the rural community sewerage improvement project directly. The conclusion of the investigation is as follows in regards to the expectations and anxieties of the inhabitant consciousness of this project:
(1) They expect comfortable mental effects, and that this project will stimulate an increase of efficiency for residence environment improvement and water environment conservation and improvement.
(2) They also expect improvement of personal life and agricultural production environments.
On the other hand, anxiety regarding this project is as follows:
(3) They are afraid of troubles related to complication of management and maintenance costs, project enforcement, spot selection and decision of facilities, cost performance, design of the structure and daily operation.
From their own evaluations for the various kind of availabilities of this project the spiritual effects are in the highest rank. Then these effects stimulale the affected availabilities of risidence environment inprovement and water environment conservations and improvement. Finally as the conclusion this project will be benefitted to enforce the development of the rural community based on resident participation.

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The purpose of this paper is to make clear the inhabitant consciousness of the various functions of the rural community sewerage improvement project. The concrete conclusion of the investigation is as follows;
(1) The DEMATEL method is available for adequately grasping an understanding of the concerned synthetic constitution of the inhabitant consciousess.
(2) The representative effective terms are personal life environment improvement, water environment conservation and improvement, mental effects, agricultural production environment improvementand residence environment improvement.
(3) Among the characteristic effects, agricultural production and personal life environment improvement affect water environment conservation and improvement and mental effects.
(4) Expectations for the rural community sewerage improvement project is complicated, because of various feedback among the effective terms.
In addition to above results while the project is promoted actually, the activities to improve the domestic residence environment is promoted and this investigation suggest that the various projects to support the development of local activities of the inhabitant including farmers and others are able to yield finally.

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The results of thermal stress analysis in concrete structure are influenced by coefficient of thermal expansion and elastic modulus which are used as parameters.
In this paper the coefficient of thermal expansion and elastic modulus to need for exact thermal stress analysis of internal restraining thermal stress were considered by using measured temperature, strain and thermal stress of concrete at the upper slab of a real RC box culvert.
First, coefficient of thermal expansion was considered by dividing into two section that rising and falling section of inner temperature of concrete. According to the results, coefficient of thermal expansion on rising section was larger than that on falling section.
Then, elastic modulus was considered by four methods. And, thermal stress were calculated by three-dimensional finite element method using four methods of elastic modulus were comparing with the measured thermal stress. According to the results, we could consider the more effective method for selecting elastic modulus to analyze internal restraining thermal stress using threedimensional finite element method.

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Analytical solution of the displacement for a two-dimensional elastic body with a finite depth subjected to normal load on the surface was obtained using a stress function. Applicability of it to a semi-infinite elastic body was discussed. Effects of size on the stresses of an elastic body with a finite size were also investigated by an analytical solution and numerical results. In addition, applicability of the photoelasticity to the semi-infinite body was investigated. Results obtained indicated that the vertical surface displacement of the elastic body resting on the rigid base did not converged to a constant value with an increase in the ratio of depth of the elastic body to loading width. So, it was impossible to estimate vertical surface displacement of the semi-infinite elastic body. Vertical normal stresses near the loading band of the semi-infinite elastic body and the elastic body with a finite size had similar values, but the maximum shearing stresses of these bodies resulted in different values. Accordingly, it was concluded that the results of the compression test using soil pit were applicable to the vertical normal stress of the semi-infinite elastic body, but the results of photoelastic study were not easily applicable to the stress of the semi-infinite body subjected to distributed load.

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EC, T-N and NO₃-N concentrations in stream waters were measured at 6 pasture districts (3 are pasturage areas and 3 are housing areas).
As a result, stocking density of cattle and NO₃-N concentration had a high correlation. Nitrogen concentration becomes high with the increase of stocking density of cattle. However the effect of cattle farms on the N concentration of stream water is smaller than pig farms with unlined storage ponds. The effluent rate of nitrogen by cattle is estimated as less than 10%.
Stocking density is limited by feed plants harvest in the pasture areas, and usually the stocking density is low (<2 heads/ha per pasture area), and the N concentration is low (T-N<4.4mg/l, NO₃-N <3.0mg/l). Then the influence of non-point sources (upland fields etc.) as noise on the N concentration of stream waters must be considered, and the difference of the amount of precipitation should also be considered. If the precipitation is large, the concentration will decrease.
N concentration of stream water in pasturage areas is lower than that in housing areas. In pasturage areas, there are cattle during the growing season of feed plants and not in winter, so pasturage intensity (CD (Cow Day)/ha or AUD/ha) is more suitable for use than stocking density.
In slurrygation areas, N concentration is lower than in the other areas.

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The series tank model has been developed for daily NO₃-N loads from an agricultural area during the non-irrigation period. The structure of this model divides the watershed into two parts. One is the upland tank, the other is the lowland tank. In this report, the author calls it a parallel type model. Daily NO₃-N loads are calculated by the model which is applied in two types of method. One is the LQ method. In this study, four types of LQ equation are used. There are two kinds of straight type (L=aQ+b, monthly and a term) and two kinds of curved type (L=aQ^b, monthly and a term). The other is the C. C. method.
The author makes three simple types of model in which the number of upland and lowland tanks are changed (4+2, 2+2 and 1+1 model), and their accuracy is compared.
Results are as follows:
1) The difference between the 4+2 model and the 2+2 model is very slight, but the result of the 1+1 model is worse than these two.
2) The LQ methods can estimate daily NO₃-N loads within less than ± 3% of the balance error ratio. Relative error ratios of monthly LQ equation methods are about 15%, but relative error ratios of a term LQ equation methods are from about 22 to about 23%, and are worse than the 15% of monthly LQ equation methods.
3) The C. C. method can estimate daily NO₃-N loads within-3.3% of the balance error ratio and about 15% of the relative error ratio. Even though concentration coefficients are constant, there is no serious problem during the non-irrigation period.

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Paddies in hilly rural areas are supposed to have beneficial effects on the environment and many valuable functions, such as flood prevention and the fostering of water resources etc., when it is appropriately used and managed by farmers. However, farm lands in adverse conditions of water and terrain in rural areas have been abandoned due to the aging of farmers. No research has been done on the effects of the abandoned farm lands on runoff except for some assumptive results estimated using a model. In this paper, the change of runoff characteristics due to the abandonment of rice cultivation in hilly areas was examined, based on the observed runoff and soil sample data from both cultivated and abandoned paddy fields. In addition, the relation between soil and water and runoff properties was analyzed in connection with unusual weather conditions such as a long rain spell in the summer of 1993 and a severe drought in 1994. The results obtained are summarized as follows:
1) It was shown that the successive change of runoff mechanism tended to occur with a paddy field abandoned in a hilly rural area of the Hokuriku region. That is, the runoff ratio and runoff peaks remained increased for 5 years after its abandonment in these areas and thus paddies there had had the function of flood mitigation during that period. However, the tendency of increased runoff was completely reversed after the occurrence of the abnormal drought, i. e. the amount of runoff from the abandoned paddies was remarkably reduced after it.
2) The above-mentioned change in runoff in the abandoned plot was explained by the existence of flow routes on the surface before the drought and an increase in the number of cracks and macropores in the soil after the drought.
3) It was shown that the abandoned paddies are affected by a long spell of rainy weather in summer and abnormal drought, but their influence on the cultivated paddies is minimized because of maintenance and rehabilitation by farmers such as irrigation, puddling, the repair of soil cracks and so on.
4) Surface runoff from sloped levees is prone to occur rather quicker than that from planting lots, and the amount of runoff tends to be bigger due to the steep slope in hilly areas. These characteristics have to be considered in handling the runoff from farm lands in hilly rural areas because the area of sloped levees in those areas is not negligible.
5) One of the characteristics in the abandoned paddies is that the water level and soil moisture under the ground surface vary from place to place, such as mountains or valleys on the sides of the plot. These differences are factors which need to be examined in dealing with the runoff from paddies in hilly areas.

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In order to evaluate the performance of structures for generating upwelling, a numerical physical-biological coupled model is presented. The model consists of two submodels: hydrodynamical model and phytoplankton dynamical model. Moreover the hydrodynamical model comprises two submodels tidal current (TC) submodel and residual current (RC) submodel. The TC and RC are computed by using multi-leveled prognostic and diagnostic models, respectively.
At first, the flow simulation is conducted in a large domain, which encompasses the study area, with large computational cells to obtain the boundary values of the study area, and then the computation is conducted in the study area with small cells by using resultant boundary values. The TC in the study area is driven by the water surface elevation at open boundaries, whose values are obtained in advance from the computation in the large domain. The RC in the study area is made by interpolating the result of RC in the large domain into the values of every small computational cell in the study area through MASCON model so as to satisfy the continuity condition.
In the phytoplankton dynamical model, the flux of phosphorus as a limiting nutrient of primary production, between two compartments: dissolved nutrient and phytoplankton, is computed in the resulting flow field. The phytoplankton uptakes the nutrient upwelled by the structures and increases. The growth rate of phytoplankton is controlled by nutrient availability, water temperature and solar radiation in this model.
This developed model is verified in comparison with the satellite observation data. This model will be a powerful tool for assessing the future projects of developing new fishing grounds with artificially generated upwelling.

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The occurrence of both epidermic browning and blackening of lotus rhizome makes its market value lower. To prevent them, it is necessary to understand the better conditions of the lotus field for the land consolidation works. Therefore, the relationship between Eh in the plow layer, and the occurrence of both epidermic browning and blackening were examined, considering the various factors which influence Eh in situ.
The results are as follows:
1) Both epidermic brown and black substance was consisted of iron.
2) The adhesion of both epidermic brown and black substance was recognized under the condition where the value of Eh is above-100 mV in the deeper part of plow layer. The higher Eh in the plow layer went up, the more the amount of its adhesion became.
3) Eh was low in summer, but it increased gradually from the upper part of plow layer with the falling of temperature in winter. Therefore, it is necessary to control Eh low enough to prevent the adhesion of epidermic substances, until the harvest season.
4) If compered rhizosphere soil among different sites at the same time, the adhesion of both epidermic brown and black substance was less as the content of free iron oxide was lower, and the content of soil organic matter was higher.

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The quantitative distributions of soil organic matter, free iron oxide, and value of Eh in the plow layer at lotus field, which influence the occurrence of epidermic blackening and browning of lotus rhizome, were measured. Then we considered the effects of hydraulic and soil conditions on Eh, and proposed the conditions of lotus field required for land consolidation works to prevent epidermic blackening and browning.
The results are as follows:
1) The amount of soil organic matter was in proportion to the content of clay, whether organic fertilizer had applied or not.
2) The clayey soil contained a lot of free iron oxide, where accumulated in the rhizosphere soil, especially in the fields which a large amount of organic fertilizer was applied.
3) Eh increased in winter at the sides of the drainage canal or paddy field with no ponding water.
4) The lager quantity of percolation at a side of the field in winter there was, the higher Eh became.
5) Therefore, it is required to restrain percolation.

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It is usually impossible to continuously carry out hydrological observations in a mountainous basin located at the high elevation for the reason that a water level recorder and others can't be operated due to snow cover and/or freezing. In the given experimental basin at the east of Yatsugatake volcanic zone, the observation of streamflow could successfully be carried out during one winter season, so we could continuously collect basic hydrological data for nineteen monthes with the given level of accuracy required.
In this paper, we discuss the hydrological characteristics of small mountainous basin covered with volcanic pyroclastic materials through the time series analysis of hydrological observed data, the determination of runoff characteristics, and the examination for the identified parameter values of tank model.
Firstly it is shown that the volume of baseflow is almost constant during no-rain season because the water storage capacity is great, and a grouping of data created by the separation of high and low flow component is convenient for the examination of relation between rainfall and discharge at the flood event. Secondly the authors give that there is a relation between the recession constant of compound recession curve and the parameter values of tank model, and finally it is explained that the diurnal variation of discharge may depend on one of solar radiation.

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1) Analysis of National Land Agency using people's satisfaction proves that improvement of facilities on living environment in farm district mainly composed of hill and mountainious areas is still far behind that in urban district.
2) Although the report of National Land Agency states that improvement of social capital should be changed from civil-minimum to amenity-minimum, civil-minimum improvement has not yet been fully implemented in farm district.
3) The report also states that every municipality can be classified into any development atages of urban area. However, urban area should not be the final development stage of farm district as farm district has different development stages from urban area considering financial capability of municipality.
4) Investment effect is higher in farm district while it is decreasing in urban area. Signification of improvement of social capital in farm district is very important.
5) Agricultural environmental improvement survey states that every municipality strongly demands total and comprehensive improvement of foundation for agricultural productivity as well as improvement of facilities on living environment. In case of implementation, comprehending the real state of region and financial support are important.
6) Agricultural infrastructure improvement has also development stages of improvement. It is important to draw final development aspect of farm district for implementation of improvement.

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