Travel cost method is one of the most prevailing approaches to estimate the benefit of natural environment. However, the high survey expense limits its application. What is now required is to develop new survey method which needs less cost. One possibility may be to utilize existing data: for example, data of permit or registration form can be used for estimation. In this paper, we use the latter data to estimate the benefits of Kiritappu wetland located in eastern Hokkaido.
Registration form is one kind of on-site data, but it has some difference since it is composed of the data of whole seasons. Usually, on-site survey is conducted in a certain period of the year, which may cause bias in the estimated benefit, especially when the living place distribution of samples (visitors to the site) is widely different from that of samples collected through the year.
We treated this issue by using registration form. Estimated benefits of the certain period and whole seasons are 1200 million yen and 2024 million yen, respectively. It suggests that estimation using a certain period on-site data may cause bias.

抄録全体を表示

The necessities of the waterside improvement in rural area has increased. And, it is necessary to quantify the resident who obtains the recreation and amenity function to improve those functions of waterside. Therefore, the purpose of this research was to make the resident population corresponding to the distance from the waterside an index as a number of beneficiaries potential those functions of waterside.
First of all, the method for estimating the detailed population distribution data was developed for that. The residential area was selected by using the detailed digital information (10m grid land use data). And, the population of each small region unit was divided in proportion by the residential area, and population distribution data of 10m mesh cell was presumed. The distributed population was estimated from three kinds of residential areas by multipul regression analysis, and the value was corrected by the total population of each small region units.
Next, the population distribution map was used to estimate for the amount of resident in the area where water is recognized. And, the section of the waterway where the waterside function was high was clarified according to the totaled area population putting weight on the distance from the waterside. These values can be used to plan the waterside as an index when the necessity and the effect of the waterside improvement are evaluated.

抄録全体を表示

A detailed land use plan is necessary to conserve farmland in disadvantaged areas. Although many studies have been done on land classification for farmland preservation, little has been done on the economic measure based method as applied to detailed land use planning. This paper presents an economic land classification method for farmland preservation.
We chose 83 plots of farmland in the mountainous area of Ohda City, Shimane Prefecture as a case study. Serious farm abandonment and subsequent problems including no insect management and wild boar damage to rice crops have occurred because of the aging and depopulation of farm households and stagnant price of rice products.
First, land productivity of each plot was estimated by a logistic regression model with surveyed farm data including farmland yield, area, damage by wild boars, rice lodging and solar radiation. The survey was conducted from August to September in 2002. Second, an estimation function for labor productivity was determined by substituting harvest time, farmland area, length of the short side of a farm field and probability of rice lodging in the model. The estimation successfully fit the harvesting time stated by each farmer. Subsequently, a mathematical programming model was constructed to estimate the expected income under the given conditions. Negative externality by neighboring abandoned farmlands, irrigation facilitymanagement and movement frequency between fields were considered in the model.
As a result, optimal land use plans were developed under the given labor input. In the simulated case where scattered abandonment occurred, the effect of negative externality was larger than that for the optimized case. We also simulated the effects of particular farmland conservation on environmental and other concerns.
The advantage of this method is that we can determine which land plots should be conserved by economic measures in definite consideration of political effects and special characteristics such as negative externality or movement frequency. For improvement of the model, data reliability of the externality effect needs to be extended. Year round labor input and multiple subjects should also be considered in the model.

抄録全体を表示