RESEARCH PROGRESS ON POLLEN-BASED FLORISTIC DIVERSITY CHANGE AND ITS MECHANISM SINCE THE LAST GLACIAL MAXIMUM
The understanding of floristic diversity changes and their response mechanisms to climate serve as the scientific foundation for future global change modeling and biodiversity conservation decision-making.The long-term changes in vegetation diversity in the past provide valuable insights into predicting ecosystem changes under analogous warming scenarios in the future.A number of researchers have focused on reconstructing past floristic diversity using fossil palynological diversity.This paper reviews quantitative indices of palynological diversity,trends of reconstructed floristic diversity across various regions since the Last Glacial Maximum(LGM),and their influencing factors.Diversity indices are composed of intrinsic indices,like richness and evenness,and a difference index of β index,which comprehensively measure diverse aspects of diversity change.Based on integration of records from various regions,floristic diversity changes since the LGM can be divided into five stages,each exhibiting distinct spatial variations amidst an overall upward trend.There were two periods of rapid increase in floristic diversity,occurring during 15～11 ka B.P.and around 4ka B.P.,respectively.Natural factors such as climate,along with unnatural disturbances like human activities,were major drivers affecting past diversity patterns.It's suggested that the long-term changes of floristic diversity were predominantly influenced by climate change,whereas during the Late Holocene,human activities exerted a significantly greater impact on vegetation diversity than natural variability driven solely by climate change.Therefore,it is crucial to recognize that observed declines in biodiversity and even extinctions since the Anthropocene are primarily caused by human activity rather than global warming.
paleo-floristic diversitypalynological diversityLast Glacial Maximummechanism of diversity change
万方数据
维普
