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本文依据南海北部珠江口ZXZ2钻孔的孢粉记录,从下至上划分了4个孢粉组合带,从孢粉成分的变化,重建了27000 a BP以来的植被和气候变化历史。研究结果发现,23100 a BP-27650 aBP期间研究区花粉特征反映了热带、亚热带温暖潮湿气候条件下的天然山地常绿阔叶林。沉积物为灰色粘土质粉砂和砂—粉砂—粘土,属近岸滨海、溺谷湾相环境,处于亚间冰期末期。16800 a BP-23100 a BP期间花粉浓度最大,其中主要的贡献是再沉积孢粉,它们主要见于冰期沉积中。沉积物露出水面,发育了一套以粉砂质砂为主的陆相冲积层。4600-16800 a BP期间,本区沉积了一套以砂质粉砂、粘土质粉砂及粘土为主的海相层。总体上孢粉较少,热带亚热带植物花粉种属减少,反映了气候温凉条件下的山地常绿阔叶—针叶混交林,林下蕨类植物很繁盛。0-4600 a BP,本区进入河口湾环境,已基本形成珠江入海的口门之一,人类活动对沿岸植被产生破坏,热带、亚热带常绿阔叶及-针叶混交林消失殆尽。
Based on the sporopollen records of borehole ZXZ2 in the Pearl River Estuary in the northern South China Sea, four sporopollen assemblages were identified from the bottom to the top. From the change of sporopollen composition, the history of vegetation and climate change since 27000 a BP was reconstructed. The results showed that the pollen characteristics of the study area during 23100 a BP-27650 aBP reflected the natural mountain evergreen broad-leaved forest in tropical and subtropical warm and humid climates. Sediments are gray clay silt and sand - silt - clay, is a coastal shore, drowning Bay phase environment, in the end of the inter-Arctic. The largest pollen concentration was 16800 a BP-23100 a BP, of which the major contribution was the re-deposition of sporopollen which mainly found in glacial deposition. Sediment exposed the surface of the water, the development of a silty sand-based continental alluvial layer. During the period of 4600-16800 a BP, a set of marine facies was deposited in this area consisting of sandy silt, clayey silt and clay. In general, spores were less and the species of tropical and subtropical pollen decreased. It reflected the evergreen broad-leaved-mountain mixed forest in mountainous climate with warm and cool conditions, and the ferns under the forest were very prosperous. 0-4600 a BP. The area has entered the estuarine environment and has basically formed one of the major entrances into the sea of the Pearl River. Human activities have caused damage to the coastal vegetation, and tropical and subtropical evergreen broad-leaved and mixed coniferous forests have disappeared.