雲南省北西部山地の移動牧畜における移動ルートと家畜分布--社会環境の変化に着目して家畜と放牧地のバランスを探る試み (特集 地域研究の前線)

Abstract

Overgrazing in mobile pastoralism does not merely mean the disruption of the quantitative balance between rangeland and livestock, but also is related with biased livestock distribution which results from social environmental changes such as road construction or land enclosure. This situation also applies to mountain areas, which hitherto have been considered to be isolated by their topographic features. These areas have recently seen rapid changes in their subsistence economy as the relation between mountain and lowland has grown closer. Therefore it is necessary to reexamine the model for dealing with mountain pastoralism in the light of recent changes. This study aims to clarify the transition of mountain mobile pastoralism under the infl uence of social environmental changes in China. A fi eld survey was conducted in a Tibetan village in northwestern Yunnan Province. Since the Yak (Bos grunniens), which is the main constituent of herds, has low tolerance to the summer heat, herds gradually go up to the higher rangeland from spring to summer. The alpine grassland located above the timberline is evaluated as the most suitable rangeland, but it is inadequate for spring or autumn grazing because of snow and frost. Mobile pastoralism is broadly conducted under the constraints of vegetation and air temperature, but the distribution of individual herds is minutely decided by arrangements among villagers. Since there have been many disputes over the mountain pasture with neighboring villages since the 1980s, these arrangements are made to protect their pasture from encroachment of neighboring herds. The mobile pastoralism is always changing in response to natural and social environments. In grasping the rangeland use of mobile pastoralism, it is important to consider the natural and social value of each rangeland.