The human and natural factors complicit in the driving forces of oasis change have always received considerable interest from the international research community. In this study, we used principal component analysis of natural and socioeconomic statistical factors to quantitatively analyze the causal relationships and their contributions to the observed periodic expansion or shrinkage of the Minqin Oasis over almost 60 years. Our results show that human factors were the dominant factors governing expansion or shrinkage, with average contributions of 69.38% and 76.16%, respectively. Moreover, policy decisions have been the pivotal human factors. Under the influence of various policies, we have found that water resource utilization, land reclamation, population explosion, ecological protection and economic development have each played leading roles in different periods. This study provides a scientific basis for modelling the dynamics of an oasis for sustainable management.

中文翻译：

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近60年来石羊河下游绿洲变化自然因素和人为因素的定量分析。

绿洲变化驱动力中的人为因素和自然因素一直受到国际研究界的极大关注。在这项研究中，我们使用了自然和社会经济统计因素的主成分分析来定量分析因果关系及其对民勤绿洲近60年周期性扩张或收缩的贡献。我们的结果表明，人为因素是控制膨胀或收缩的主要因素，平均贡献分别为69.38％和76.16％。此外，政策决定已成为关键的人为因素。在各种政策的影响下，我们发现水资源利用，土地开垦，人口爆炸，生态保护和经济发展在不同时期均起着主导作用。该研究为为可持续管理的绿洲动力学建模提供了科学依据。