Plant responses to climate and other environmental changes can inform our understanding of how these changes affect ecosystem function and productivity. For example, plant phenology can be a useful proxy for temperature in historical climatology, and the biological impact of climate change and global warming. Palynology, the analysis of fossil pollen deposits in sediments from thousands or millions of years ago allows the reconstruction of past climates. Estimates of atmospheric CO2 concentrations since the Palaeozoic have been obtained from stomatal densities and the leaf shapes and sizes of ancient land plants. Ozone depletion can expose plants to higher levels of ultraviolet radiation-B (UV-B), resulting in lower growth rates. Moreover, information from studies of community ecology, plant systematics, and taxonomy is essential to understanding vegetation change, habitat destruction and species extinction. COUNT 5
QSN1 How can historical changes in the environment be detected? ANS1 plant phenology QSN2 How can climate changes be determined from soil? ANS2 fossil pollen deposits in sediments QSN3 What atmospheric gas can be determined from fossilized leaf sizes and shapes? ANS3 CO2 QSN4 What causes lower growth in plants? ANS4 Ozone depletion QSN5 What does ozone depletion allow? ANS5 higher levels of ultraviolet radiation-B