Relationship between spatial distribution of vegetation and surface pollen in northern Xinjiang, Northwest China

Northern Xinjiang covers a vast area with distinct regional differences in vegetation distribution. In this study, vegetation coverage was statistically assessed, and pollen assemblages and pollen spectra were established through systematic vegetation surveys and surface soil pollen analysis in this region. This study explores the distribution characteristics, relationships, and influencing factors of vegetation and pollen in northern Xinjiang, China. The results indicated that herbaceous plants belonging to families and genera such as Chenopodiaceae, Artemisia, Poaceae, and Cyperaceae are widely distributed with highvegetation coverage in northern Xinjiang. Arboreal and herbaceous pollen were dominant in the pollen assemblage. The arboreal pollen primarily consisted of Picea and Pinus pollen. The R-value analysis demonstrated that Picea and Pinus pollen, both of which often originated from external sources, exhibited high production and were highly represented. High concentrations of Ephedra pollen were typically found near Ephedra distribution sites, indicating a correlation with vegetation coverage. Chenopodiaceae and Artemisia pollen were widely distributed across northern Xinjiang and were highly represented. Poaceae, Asteraceae, Cyperaceae, and Polygonaceae pollen generally showed low representation. However, influenced by climate, wind, and topography, the percentages of Asteraceae and Cyperaceae pollen in the Ertix River valley and Laofengkou were high for their vegetation coverage and were highly represented.Principal component analysis of surface pollen data revealed that pollen distribution in the Kanas Lake watershed, Laofengkou-Mayitas wind corridor, western Tianshan Mountains, and western Altai Mountains was jointly influenced by temperature and precipitation factors, whereas that in the Ertix River valley and Baili wind corridor was primarily controlled by precipitation. This study establishes a theoretical foundation for the quantitative reconstruction of the paleoclimate and paleoenvironment in northern Xinjiang using fossil pollen.