Rapid dynamics of paraglacial vegetation under temperate deglaciating environments in Mt. Gongga, southeastern Tibetan Plateau
摘要
Investigating the spatial distribution of vegetation in monsoonal-climate-dominated high mountain area and detecting its changes that occurred in paraglacial areas is crucial for understanding the cascading environmental effects of shrinking glaciers. We used Landsat images from 1994 to 2022, obtained landscape distribution patterns of glaciers and vegetation in Mt. Gongga, and detected paraglacial vegetation changes under deglaciating environments. We observed there is a pronounced difference in glacier and vegetation coverage between the eastern and western slopes in Mt. Gongga, the eastern slope occupies 78.68% of vegetation area and 61.02% of glacier area, whilst the western slope occupies lower area. Exaggerate warming accelerated glacier retreat, and proglacial areas are generally characterized by very fast primary succession, resulting in an increase of 0.32 km2 in vegetation area within two typical glacier forefields on the eastern slope. The phenomenon of paraglacial slope failure following glacier thinning is widespread in Mt. Gongga, resulting in vegetation area decreased by 0.34 km2. Concurrently, the fast retreat of glaciers and changes in ice surface geomorphology have caused rapid dynamics in supraglacial vegetation developed on its lower debris-covered sections. We suggested that rapid changes of temperate glaciers can significantly influence paraglacial landform, leading to rapid dynamic changes of vegetation in a balance between colonization and destruction.