Mt. Tairappyo (1, 983. 7m a. s. l.) is a middle mountain located in the Mikuni range, central Japan. The summit of this mountain has a saddle-like ridge extending to east. Along this gentle ridge many patch barelands which stretch from south to north are distributed. They often form steps similar to turf-banked terrasses. Though surfaces of barelands are almost flat, there exist turf scarps or notches about 20cm high at the northern margins. This study was made to clarify the processes and rates of turf scarp denudation in patch barelands. We measured the rates of turf scarp retreat in seven barelands and gained average recessional rate of 1.8cm/year. This value exceeds the velosity of 0.69cm/year reported from high mountain in Benezuelan Andes by Perez (1992). Barelands are considered to have been enlarged in consequence of turf scarp denudation at their northern margins.
Erosional processes on turf scarps are as follows. In April and May rubbles on turf scarps become loose by melting of frozen ground and soils on turf scarps are loosened by needle ice activity. Soils are dried up from May to July, and soil particles are denudated by strong south wind which constricted at narrow cols on mountain ridge. In August and September wind erosion becomes weak and turf scarp retreat is little. In October denudation becomes active on account of strong winds and severe rains. Though freeze-thaw cycle starts again in November, snow cover and protection of withered grass reduce turf scarp retreat. In winter erosion is very little because of ground freezing. And snow covers protect earth surface. As upper part of turf scarps are tightened by root systems, denudation of turf scarps accelerates at their bases and as a result of erosion turf scarps change to notches with eaves. After a while eaves collapse and new turf scarps are formed.
In Japan, patch bareland on high mountains are considered to be formed mainly by prevailing northwestern winter monsoon. However, in Mt. Tairappyo barelands are formed by south wind of spring and autum. It is extremely characteristic.

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One adverse impact by tourism in the Nepal Himalaya is deforestation resulting from the use of wood for fuel. The magnitude of this impact, however, has not yet been understood well. As a first step to gain such an understanding the number of visitors to Sagarmatha (Mount Everest) and Langtang National Parks was estimated for the period of 1990-94. Group and individual styles of trekking were distinguished because they exhibit different wood burning behavior, with individual trekkers consuming fuelwood at “hotels”. Overall, 7, 077 group trekkers and 4, 629 individual trekkers visited Sagarmatha NP. The respective totals for Langtang NP were 3, 397 and 4, 964. The 1990 and 1994 surveys indicate that there were 3.75 guides and porters per group trekker and only 0.23 guides and porters (including porterage by yaks) per individual trekker in Sagarmatha NP. The corresponding ratios for Langtang NP are estimated as 1:3.14 for group trekking and 1:0.32 for individual trekking. In Sagarmatha NP the number of guides and porters is divided almost equally between trekking agency staff from Kathmandu and local porters. In Langtang NP local porters constitute nearly two thirds of the total. Among all these visitors, the average annual number of people who could contribute directly to wood consumption (i. e., individual trekkers, their guides/porters, and local porters for group trekkers) and the average length of their stay were multiplied to evaluate their impact in the two park areas. The calculated total number to Sagarmatha NP was 24×10⁴ visitor·days and that to Langtang NP was 20×10⁴ visitor·days. A reduction in impacts to forests may be possible if the following two goals can be achieved: (1) reducing wood consumption by individual trekkers and their guides and porters at “hotels, ” and (2) reducing wood consumption by local porters along trails. Some specific measures to reduce wood consumption in the Nepal Himalaya are presented.

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