论文部分内容阅读
青藏高原的强烈上升对北半球大气环流起重要作用并控制东亚季风的形成和发展。西藏佩枯错 13ka 5kaB .P .高密度样品孢粉分析表明 :约 12 5 0 0aB .P .湿度加强 ,区域性植被中雪松占优势 ,莎草草原大发展 ;约10 76 0aB .P .气候冷干 ,莎草草原分布范围减少 ,雪松成分降低 ,可能与欧洲YoungerDryas事件相当 ;10 0 0 0aB .P .左右是本区气候变化的转折点 ,湿度迅速增加 ,沙棘增多 ,雪松林占优势 ;912 5— 86 0 0aB .P .莎草草原中灌丛成分增加 ,除沙棘外 ,有柳、锦鸡儿、杜鹃等 ;10 0 0 0— 6 80 0a .B .P .干旱逐渐加强 ,约 6 80 0aB .P .达干旱高峰 ;86 0 0— 6 80 0aB .P .间气候冷干 ,禾草、蒿草草原取代莎草草原 ,草原植被中藜科、麻黄、白刺增多 ,区域性植被松、高山栎、铁杉林占优势 ;6 80 0— 6 6 35aB .P .间湖水淡化 ,水生植物狐尾藻、菜等有出现 ;佩枯错 13ka— 5kaB .P .间出现 3次湿润高峰 ,它们分别为 :12 .5ka、10ka、6kaB .P .。湿度的增加可能与夏季风的加强有关。
The strong rise of the Tibetan Plateau plays an important role in the atmospheric circulation in the northern hemisphere and controls the formation and development of the East Asian monsoon. The analysis of sporopollen in high-density samples from Peiju fault in Tibet shows that: about 12500aB.P. Humidity is stronger, and the dominant species of cedar are in the regional vegetation, while the savannah is greatly developed; Cold and dry seasons, reduced senescence and reduced cedar composition may be similar to the Younger Dryas event in Europe; the turning point of climate change in this area is about 100o 0 ° a. The humidity increases rapidly, the seabuckthorn increases, and the cedar forest predominates. 912 5-86 0 0 aB. P. Sedge grasslands in the shrub composition increased, in addition to seabuckthorn, there Liu, Caragana, rhododendron, etc .; 10 0 0 0 - 6 80 0a .B. P. drought gradually strengthened, about 6 80 0aB.P. Drought drought peak; 86 0 0 - 6 80 0aB. P inter-climate cold and dry, grass, grass steppe replaces sedge steppe, grassland vegetation Chenopodiaceae, ephedra, white thorn increased, regional vegetation , Alpine oak, hemlock forest dominated; 6 80 0- 6 6 35aB .P between the lake water desalination, aquatic plants such as foxtail, kohlrabi and so on have appeared; Pekoe mist between 13ka-5kaB. P between 3 wet peak , They are: 12 .5ka, 10ka, 6kaB. P .. Humidity increase may be related to the strengthening of the summer monsoon.