Surface soil pollen and climate in northern Xinjiang, China: Implications for paleoclimate reconstruction

Abstract

Quantitative paleoclimate reconstruction based on surface soil pollen and climate records on a regional scale is widely applied as a standard approach to investigating past climate changes. This study aimed to explore the quantitative relationships between the distribution of pollen taxa in 438 pollen samples from surface soils at altitudes ranging from 190 m to 3235 m and 19 environmental parameters in northern Xinjiang, China, using ordination and correlation analyses. The results showed that mean annual precipitation (MAP), precipitation in July, mean annual temperature (MAT), mean temperature in July and mean annual wind speed were the main environmental factors influencing the surface pollen distribution. Pinus pollen dispersal and transportation were primarily affected by spring wind, suggesting that exotic pollen played an essential role in surface pollen distribution. Picea pollen, with a percentage and concentration of over 30% and 30000 grains/g, was distributed at sites with MAT and MAP of −5.1–1.2 °C and 212–459 mm, respectively. Artemisia and Chenopodiaceae, with percentages and concentrations of over 50% and 50,000 grains/g and 50% and 10,000 grains/g, respectively, were mainly distributed at sites with MAT and MAP of −1.9–9.1 °C and 145–416 mm, and −3.2–8.9 °C and 129–449 mm, respectively, providing an accurate reference for paleoclimates reconstruction. This study presents information regarding the relationship between surface soil pollen and climate records, which may contribute to the reconstruction of historical climates, promote ecological development in Xinjiang, China, and assist in predicting future climate trends.