GONG Hongmei1,2, CHEN Jingyi1, TIAN Peng1, ZENG Shufang1, LI Xianming1,
TANG Haopeng1, WANG Xun2, WANG Yongmin1, WANG Dingyong1

（1. College of Resources and Environment, Southwest University, Chongqing 400715, China;

2. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China）

Abstract： Assessing the altitude distribution of mercury in alpine forest ecosystems and its influencing factors is of great significance for understanding the biogeochemical cycle of mercury. In this study, we determined the contents of Hg, C and N in leaves, O-horizon soil, topsoil (0-20 cm) and profile soil (0-100 cm) on the eastern and western slopes of the Ailao Mountain. The results showed that there were no obvious altitudinal distribution trends of mercury concentrations in leaves of the Ailao Mountain, also no significant differences of Hg concentrations between coniferous and broad-leaved tree species. Mercury concentrations in O-horizon soil increased with the increase of soil depth, negatively correlated with carbon content and positively correlated with nitrogen content. Hg concentration in topsoil (0-20 cm) and the background value of soil mercury (60-100 cm deep soil mercury concentrations) increased with the increase of altitude. Mercury concentrations in topsoil were positively correlated with annual rainfall, carbon content and nitrogen content, and negatively correlated with annual average temperature. The results showed that there is an obvious altitudinal distribution pattern of soil mercury in the Ailao Mountain Alpine forest, which is affected by geological background, climate, soil organic matter and its mineralization degree.

Key words：Alpine forest; soil; mercury; influence factor

EARTH AND ENVIRONMENT Vol.51, No.3, Tot No.353, 2023, Page 338