1. Basic Viewpoint on the Maintenanace and Reallocation of Urban Environments
(1) Concept of the Urban Environmental System
An urban environment with its organic relations of natural, social and economic facilities constitutes a system of its own. Consequently an urban environmental system should be defined not only by its ecological and natural conditions, but social and economic conditions, and its efficiency and safety should be guaranteed for the total of these conditions.
(2) Analysis of Indicators of Urban Environments
In order to grasp the conditions of an urban environmental system, indicators of urban environments were set and their overall analysis was attempted. First, the situation of air pollution was analyzed by means of indicator plants, and the degrees of pollution were classified into several ranks for the analysis of local ecological conditions.
Secondly, the socio-economic conditions centering around the supply conditions of public goods were compared between various localities (with a city, town, or village, as a unit of comparison) to examine the levels of distribution of public goods.
Thirdly, the degree of urbanization and the distribution of the residual green belts in various localities were surveyed and analyzed.
2. Classification of Green Environments
(1) Evaluation and Classification of Urban Environments
The indicators of urban environments were observed, and their overall results were used to classify the environmental conditions in the areas within a radius of 50 kilometers from the center of the metropolitan zone.
Urban areas with more than average levels of artificial environmental goods but with deteriorated conditions regarding green belts and ecological environment were found more often in the old urban area, while those areas with less than average levels of artificial environmental goods but with relatively good levels of green belts and ecological environment were frequently found in the rural areas outside the urban area. The newly developed urban areas between these two types of areas were found fraught with environmental difficulties because of inadequate methods of development. Their levels of artificial environmental goods were inadequate, and many of them faced such disruptions as rapid destruction of green belts and increasingly smaller segmentalization in the use of land. The congestion in urbanization was represented in these areas, which were urgently required to make overall solutions of the development of the urban environmental system.
(2) Evaluation and Classification of Green Environments
The levels of green environmental goods in various localities were determined through the classification of the areas by the environmental indicators, and then the functions and distribution of the green environmental goods were examined.
The green environments are largely classified into parks, farms and forests. The parks in the zone studied were generally limited in number, and their levels were far lower than those in the urban areas in the developed countries of the West. In the newly developed urban areas, farms and forests were destroyed, and their irregular developments interfered the proper progress of the land utilization. For the green areas in the zone between 30 and 50 kilometers from the metropolitan center, steps of conservation should be taken urgently in the orderly development and utilization of land.
The development and distribution of urban parks and green areas are needed as the daily area of recreation for the urban inhabitants. Regarding the green belts for agriculture and forestry as found in the Tama highland range, Miura and Boso peninsulas, steps of preservation should be taken for the green belts connecting woods in old mansions, forests in Shrines, and green areas in river beds along with the development as the suburban agricultural areas.
