Abstract:

Considering on the causes of Tibetan grassland degradation and the effects of restoring measures, the quantitative research on the causes of Tibetan grassland degradation and the efficiency of restoring measures was made using fuzzy analytical hierarchy process. The results showed that the contribution rates of overgrazing and extreme climate and adverse natural environments were 45.6 % and 30.43%, respectively, which were the main factors of Tibetan grassland degradation. The contribution rate of damage caused by rats, pests and weeds was 11.4%.The weight values of the factors of treatment measures to general objective were as follows: enclosure grasslands and rotational graze (0.2078) > cultivated grassland (0.1459) > the control of grazing intensities (0.1402) > controlling rats,pests and weeds (0.1337) > stopping unauthorized mining and devouring the herbage (0.1211) > fertilizing, mending sowing and loosening soil (0.1059) > optimizing structure of animal-flock(0.0939) > selecting and cultivating fine herbage (0.0515). Enclosure grasslands and rotational graze were effective measures in preventing Tibetan grassland degradation. Other measures could not be ignored as well. In a word, controlling Tibetan grassland degradation is a comprehensive process.

Key words: Tibet, Grassland degradation, Fuzzy analytical hierarchy process

摘要：

针对西藏草地退化的成因以及恢复治理措施的效应问题，利用模糊层次分析法，研究了西藏草地退化的成因和各种恢复治理措施的效率。结果表明，超载放牧对西藏草地退化的贡献率达到45.6%，气候变化异常、自然条件恶劣的贡献率是30.43%，两者是导致西藏草地退化的主要原因；其次是鼠虫毒杂草危害，贡献率占11.4%；治理措施层各因素对总目标权重的大小顺序为：围栏封育和划区轮牧（0.2078）> 建立人工草地（0.1459）> 降低放牧强度（0.1402）> 鼠虫和毒杂草控制（0.1337）> 停止滥挖乱采活动（0.1211）> 施肥、补播、松耙（0.1059）> 优化畜群结构（0.0939）> 优良牧草选育（0.0515）。实行围栏封育和划区轮牧是治理草地退化的有效措施，而建立人工草地、控制鼠虫和毒杂草、停止滥挖乱采活动、施肥、补播、松耙等措施也不能忽视，草地退化治理应该是一个综合治理的过程。

关键词: 西藏, 草地退化, 模糊层次分析法.