Pollen assemblages and anthropogenic influences in the central and western regions of Yunnan Province

Abstract

The goal of this study was to provide information on the representation of pollen taxa and the human impact on vegetation by exploring the relationship between modern pollen and vegetation in the central and western regions of Yunnan Province of China. A total of 120 modern pollen samples were collected throughout the study area. The surface pollen assemblage was divided into eight pollen zones (Zones I–VIII) based on vegetation types. We analyzed the palynology and determined the hemeroby levels of each zone in the area. Our results showed that human activity is one of the most important factors that can result in the damage of natural vegetation and increase anthropochory and secondary plants. The hemeroby levels of the surface pollen samples were mainly euhemerobic except for Zones I, II, and VI, which indicates a strong and continuous anthropogenic influence in the central and western regions of Yunnan Province in recent decades. The lowest hemeroby values were observed in Zone I samples, which were collected from Mengla and Jinghong. These areas are in the Xishuangbanna region, which is the most biodiverse region in China and has been well preserved since 1959. Therefore, the extent of human influence of a region can be estimated from the degree of hemeroby established from pollen data, which can be used in the future for nature conservation.