Rupelian Kazakhstan floras in the context of early Oligocene climate and vegetation in Central Asia

Abstract

AbstractThe Oligocene represents a transitional phase from a “hot‐house” to a “cold‐house” climate. Central Asia has undergone substantial environmental changes and tectonic events; however, we know little about how these tectonic events shaped the climate and biodiversity in Central Asia. Here, we present a detailed study on the early Oligocene palaeobotanical record in Kazakhstan using various qualitative and quantitative techniques of palaeoenvironmental reconstruction. According to our data, mixed mesophytic and coniferous–deciduous forest vegetation existed in a warm‐temperate, largely humid yet seasonal climate, while western Kazakhstan tended to be warmer and wetter compared to eastern Kazakhstan. Our results suggest that after the Eocene–Oligocene transition, the climate became cooler and more seasonal causing the disappearance of subtropical elements. Compared to the present‐day, the climate was substantially warmer and wetter, supporting forest vegetation in the study area.