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根据宝华山华山口和官塘头两个剖面的花粉、地层资料 ,结合植物大化石和1 4 C年代资料 ,揭示该地区从 >670 0— 560 0aBP为稳定的温暖湿润时期 ;自 560 0— 51 0 0aBP为全新世中期气候的转型时期 ,冷暖干湿变化较大 ,前期转凉 ,旱涝频繁 ,中期暖湿 ,后期转冷 ;大约从 440 0— 40 0 0aBP又变为稳定的暖湿气候。还根据自然保护区现代植被与花粉的关系和与植物大化石共生的沉积物花粉 ,阐明长江下游新石器时代以来 ,因受人为影响 ,其地区青冈栎与栲的花粉之和占孢粉总数的 1 0 .0 %左右便可能有中亚热带性质的森林存在。本地区的沉积特征表明 :侵蚀和次生黄土堆积反映不稳定气候 ,与海面下降相关 ;淤泥、泥炭堆积阶段为温暖湿润气候 ,受海面升高影响。此情况在长江下游具有一定代表性
Based on the pollen and stratum data of the two sections of Huashankou and Guantangou of Bahuashan and the data of macrofossils and ages of 14 C, it is revealed that the region from 670 0 to 560 0 aBP is in a stable warm and wet period, from 560 0- 51 0 0 aBP is a mid-Holocene climate transition period, with a greater change in temperature and humidity, with a cooler early stage and frequent droughts and floods, a warm-humid mid-term and a late-turn cooling; from about 440 0-40 0 0 a BP to a stable warm and humid climate. According to the relationship between the modern vegetation and pollen in the nature reserve and the sediment pollen coexisting with the large fossils of plants, the pollen sum of pollen of Quercus glauca There may be forests of subtropical nature at about 1.0%. Sediment characteristics in this area indicate that the erosion and secondary loess accumulation reflect the unstable climate, which is related to the sea surface descent. The silt and peat accumulation stage is warm and humid, which is affected by the sea surface elevation. This situation is representative of the lower reaches of the Yangtze River