作業道の実態について (II)

Abstract

都道府県レベルでの林道・作業道の開設実態についての調査をもとに, 昭和55年 - 59年の5ヵ年間の開設状況が森林の資源, 道路の現況, 林家の所有規模等とどのような関連があるかについて分析を行った。その結果林道等の開設長は森林の状況との関連は薄いが, 道路の現況等とは関連がある。すなわち林道の密度が高い程, 所有規模が大きい程, 林業活動が活発な程, 車両系の機械が多い程林道等の開設量は多い傾向がみられた。

In this report, we wish to consider several rerationships between the total construction length of forest roads and working roads, and some forestry factors. The total construction length in each prefecture which is shown at fig. 4, is investigated by a questionnaire against a prefectural office. The value is total construction length per hectare of private forest area, from 1980 to 1984. We consider five forestry factors which are an actual forest resources, a road density in forest, a size of owned forest area, a forest activity, and a number of owned forest machine. We group all prefectures into three or four classes every each factor according to a Cluster Analysis (Table 1-6). We consider of the relation on a comparsion of each groups average value (Table 7). It is difficult to find a certain relation between the total length of construction and the forest resource which is consisted of a percentage of forest area, plantation area and young forest area against private forest area. But, the total length is related the actual road density which is a density of forest roads, public roads, and all the sum of them, the size of owned forest area, the forest activity and the number of owned forest machine. The relation has a tendency that the value of road construction increases with increasing the actual forest road density, the size of owned forest area, the forest activity which is chararterized by forestation area and timber production, and the number of vehicles machine. Table-8 shows a result of classificatiom according to a first factor score which is calculated from Factor Analysis against each forestry factor. Each group is characterized by its value of forestry factor, and its length of construction roads is according to the relation of the characteristic forest factors.