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通过对运城盆地DXF-S和DXF-N两个全新世典型黄土-土壤剖面磁化率和炭屑浓度的分析,结合已有的研究成果,探讨了该区域野火活动和生态环境演变的基本规律。马兰黄土堆积时期,气候干旱而不稳定,植被呈现荒漠草原或半荒漠草原景观,地方性和区域性野火频繁发生;全新世早期,气候开始由冷干向温湿过渡,但仍比较干旱,野火活动仍然较为频繁,地表植被应为干草原或含有森林成分的干草原景观;全新世中期是全新世最为温暖湿润的时期,野火活动微弱,植被为温带落叶阔叶林为主的森林草原并掺杂少量亚热带植物,但在夏商文化时期,由于人为焚林、围猎、取暖、刀耕火种等生产和生活活动,使野火活动的频率提高,标志着人类开始影响生态环境演变的进程;全新世晚期,气候向干旱化发展,人类生产和生活活动范围的不断扩大,人为野火活动频繁发生,使地表的自然景观逐渐向半自然半人工景观过渡,尤其,近百年以来随着人口的大量增加,聚落规模的迅速扩大,地表已转变为农田景观。
Based on the analysis of the magnetic susceptibility and carbon concentration of two typical Holocene loess-soil profiles of DXF-S and DXF-N in Yuncheng basin and the existing research results, the basic rules of wildfire activity and ecological environment evolution in this area are discussed. During the period of accumulation of loess in Malan, the climate was arid and unstable. The landscape of vegetation showed desert steppe or semi-desert steppe. Regional and regional wildfires occurred frequently. During the early Holocene, the climate began to change from cold to dry but warm and wild, Activities are still more frequent, the surface vegetation should be steppe or steppe landscape with forest components; Mid-Holocene is the most warm and humid period of the Holocene, wildfire activity is weak, the vegetation is temperate deciduous broad-leaved forest-based grassland and mixed However, during the period of Xia and Shang Dynasties, the frequency of wildfire activities increased due to the production and living activities such as forest burning, hunting around, heating and slash-and-burn farming, which marked the beginning of human’s influence on the evolution of ecological environment. In late Holocene, The development of arid climate, the continuous expansion of the scope of human activities and living activities, and the frequent occurrence of artificial wildfire have led to the gradual transition of the natural landscape of the earth’s surface into a semi-artificial semi-artificial landscape. In particular, with the large increase in population over the past century, The rapid expansion of the surface has been transformed into farmland landscape.