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古生态学的研究显示 ,栎林 (包括蒙古栎林 )在华北地区和东北地区的分布在地质历史时期不是一成不变的 ,其优势度也呈现上下波动 ,栎树优势度的增减是由于地质历史时期气候的变化造成的 ;蒙古栎的起源时间可能不早于上新世中期 ,蒙古栎林的起源也应不早于上新世中期。蒙古栎林的起源原因有 2种 ,即火与人类的反复砍伐。火是原生性质蒙古栎林在地质历史时期存在和扩散的根本原因 ,过度的人类活动 (主要是反复砍伐 )是促成现在蒙古栎次生林占优势地位的主要原因 ,这是由蒙古栎这个树种的生物学特性决定的 ,在没有外界因素的干扰和火减少的情况下 ,蒙古栎在演替过程中逐渐被耐荫的树种所取代 ,但是在中国北方 ,由于人类活动的加剧 ,蒙古栎林的优势度有增加的趋势。
Paleoecology research shows that the distribution of Quercus mongolica (including Quercus mongolica) in North China and Northeast China is not constant in geological history, and its dominance fluctuates up and down. The increase and decrease of the dominance of the oak is due to the geological history The climate change of the period resulted in; Quercus mongolica may not originate earlier than the mid-Pliocene, the origin of Quercus mongolica forest should also not earlier than the mid-Pliocene. There are two reasons for the origin of the Mongolian oak forest, that is, the repeated felling of fire and human beings. Fire is the nature of the original nature of the Quercus mongolica forest in the geological history of the existence and proliferation of the root causes of excessive human activities (mainly repeated felling) is contributed to the dominant position of the Quercus mongolica forest is dominated by the species of Quercus mongolica In the absence of outside interference and fire reduction, Quercus mongolica is gradually replaced by shade-tolerant species in the succession process. However, in northern China, due to the intensification of human activities, the advantages of Quercus mongolica Degree has an increasing trend.