The effect of volcanism on submontane rainforest vegetation composition: Paleoecological evidence from Danau Njalau, Sumatra (Indonesia)

Volcanic processes might have played an important role in the vegetation history of Sumatra, one of the largest and most tectonically active region in Southeast Asia. Palynological and macro-charcoal analysis results from Lake Njalau in the Kerinci Seblat National Park (KSNP) in Sumatra (Indonesia) provide an understanding of interactions between the volcanic deposition and vegetation in the past 5000 years. The deposition of volcanic material in the depression of the Lake Njalau (5100–4400 cal. yr BP) led to the dominance of pioneer species of Casuarina and Myrica, which grow in deforested land and volcano slopes (volcanophile taxa). The formation of the modern forest composition took several centuries after the volcanic deposition in the soil ended (ca. 900 years at ca. 2400 cal. yr BP). This suggests that the vegetation changes were not driven by a successional pattern, and soil formation was the most important environmental factor explaining this slow change in composition. The palynological records s...