自然地理因素下的唐蕃边界变动

The Change of Tang-Tibetan Boundary under Natural Geographical Factors

唐蕃边界是唐朝周边关系中变化最为剧烈的边界走向,其变化受多种因素影响,其中自然地理是最重要的因素之一。唐蕃之间存在着一片半耕半牧区,双方的边界变动基本都在这片半耕半牧区。唐朝在强盛时,将边界向西推进到靠近青海日月山一带的半耕半牧区;在唐朝势力式微时,吐蕃又将边界向东、向北推进到靠近河套地区、关中盆地、四川盆地即贺兰山—陇山—大渡河一线的半耕半牧区。无论是唐朝还是吐蕃,双方边界的最大推进度都受到相应的自然环境的制约,无法进入对方的平原农业区和高原牧业区。因此,在考察唐蕃划界的因素中,既要考虑主观的军事力量、政治目的等人文因素,也要考虑客观的自然地理因素,从而更清晰地认识自然地理在唐蕃边界问题上的影响,更为全面地认识唐蕃关系变化的过程。

the Tang-Tibetan Boundary was the most dramatic change in the relationship around the Tang Dynasty.This change was influenced by many factors,among which physical geography was one of the most important.There is a farming-pastoral area between Tang and Tibetan and The Tang-Tibetan boundary had moved in this area.When the Tang Dynasty was strong,the boundary was pushed westwards to the farming-pastoral area near Qinghai Lake,namely Riyueshan Mountain.When the Tang Dynasty was weak,the Tibetan pushed the boundary to the farming-pastoral area near Hetao Area,Guanzhong Basin and Sichuan Basin,taking Helan Mountain,Longshan Mountain and Dadu River as the boundary.Whether Tang or Tibetan,the maximum advance of the boundary is based on the adaptation to the environment.Therefore,in the analysis of the factors of the Tang-Tibetan boundary demarcation,we should take into account both subjective human factors and objective physical geographical factors,so as to have a clearer understanding of the influence of physical geography on the Tang-Tibetan Boundary,and a more comprehensive understanding of the process of the change of the relationship between Tang and Tibetan.