关键词: 生物群区化, 植物功能型, 孢粉, 古植被定量重建, 古植被与古气候模拟

Abstract:

Quantitative palaeovegetation reconstruction is an important topic in studies of past global changes. Biomisation, an effective method of quantitatively reconstructing palaeovegetation, can translate pollen records into biome assignments based on defining biome types in terms of characteristic plant functional types and using a standard numerical method to calculate the affinity scores of pollen spectra. This review briefly introduces the history of Biomisation, its working processes and current problems. The world’s palaeovegetation patterns in the Mid-Holocene (MH) and at the last glacial maximum (LGM) including China have successfully been reconstructed using this technique. Results showed that the Arctic forest limit was shifted slightly north during the MH in some sectors, but not in all. Northern temperate forest zones were generally shifted greater distances north. Temperate deciduous forests in Europe were greatly extended into the Mediterranean region as well as to the north. Steppe encroached on forest biomes in interior North America, but not in central Asia. Enhanced monsoons extended forest biomes in China inland and Sahelian vegetation (e.g., steppe, xerophytic woods/scrubs and tropical dry forest ) into the Sahara, while the African tropical rain forest was also reduced. Cold and dry conditions at LGM, however, favored extensive tundra and steppe. These biomes intergraded in northern Eurasia. Northern hemisphere forest biomes were displaced southward. Boreal evergreen forests (taiga) and temperate deciduous forests were fragmented, while European and East Asian steppes were greatly expanded. Tropical moist forests (i.e., tropical rain forest and tropical seasonal forest) in Africa were reduced. In south-western North America, desert and steppe were replaced by open confiner woodland.

Key words: biomisation, plant functional types, pollen, palaeovegetation reconstruction, palaeovegetation and palaeoclimate modeling