To improve the quality of urban life, it is necessary to increase a chance of coming in touch with natural environment as well as urban environment. Accessibilities to various natural environments, therefore, are very important factors on making a environmental plan of a wider urban area. The purpose of the study is to find out determinant factors in the residents' evaluation of accessibilities to natural environment and to estimate the accessibilities at any point of a wider urban area.
The authors conducted a questionnaire sheet survey in Utsunomiya City which composes an independent urban area in 1989. The number of respondents of this survey is 6, 939, with collecting ratio of 52.1 percent. Using the data, the authors tried to explain residents' evaluation of accessibilities with such physical data, as distance to destination, scale and quality of destination, and such personal attributes data as age, sex, occupation, type of housing, the will of setting in one's place, and land use type around residence. The following three kinds of accessibilities were selected for the examination; to parks and open spaces, to water fronts, and to mountains.
The results of the analysis are as follows: (1) Evaluation functions for “to parks and open spaces”, “to water fronts”, and “to mountains” which use residents' evaluation and air distance were developed. They however were not proper. (2) To enhance the evaluation functions to parks and open spaces, air distance to parks which was assumed from traveling time as a explanatory variable improved the evaluation function. (3) To enhance the evaluation functions to water fronts, air distance to water fronts, distance to the center of city and water quality are effective factors in the evaluation of accessibilities to water fronts. Using this evaluation function, evaluation values at whole points of Utsunomiya City were acquired. (4) In the case of “to mountains”, there are little relationship between residents' evaluation and air distance. Therefore route distance or traveling time will be required instead of air distance to estimate an evaluation function. (5) Residents' location from the center of city effect their evaluation. In the case “to parks and open spaces”, the distance become farther, the evaluation becomes lower. And others cases “to water fronts” and “to mountains”, the distance become farther, the evaluations become higher.
Evaluation functions using air distance with other factors instead of traveling time is useful. The other hand there is limit to enhance these functions without traveling time. Therefore to use traveling time or route distance also will be required even the estimation is difficult.
