Land Plant Evolution and Weathering Rate Changes in the Devonian

摘要

INTRODUCTION The Devonian was characterized by major changes in both the terrestrial and marine biospheres. Terrestrial ecosystems were marked by large increases in biomass and complexity, evolution of trees and seed plants, appearance of multistoried forests, and formation of deeply weathered soils (Algeo and Scheckler, 1998). Rapid drawdown of atmospheric CO2 resulted in global cooling and, toward the end of the Devonian, continental glaciation. The marine realm was characterized by widespread development of bottomwater anoxia, enhanced organic carbon burial rates, and an extended biotic crisis that decimated tropical marine benthos, especially the stromatoporoid-tabulate coral reef community.