Paleoecology of late-glacial terrestrial deposits with in situ conifers from the submerged continental shelf of western canada |
| |
Authors: | Terri Lacourse Rolf W MathewesDaryl W Fedje |
| |
Institution: | a Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada b Parks Canada, Victoria, British Columbia V8W 1E2, Canada |
| |
Abstract: | Extensive portions of the continental shelf off the coast of British Columbia were subaerially exposed during Late Wisconsinan deglaciation due to lowering of relative sea level by as much as 150 m. Paleoecological analyses were conducted at two sites on the emergent continental shelf where terrestrial surfaces with in situ conifers are preserved. The woody plant remains confirm that, during the latest period of subaerial exposure, terrestrial vegetation was established on the continental shelf. Microscopic identification of fossil wood, and analyses of pollen and plant macrofossils from the associated paleosols and overlying shallow pond sediments indicate that productive Pinus contorta-dominated communities with abundant Alnus crispa and ferns grew on the shelf adjacent to and on the Queen Charlotte Islands around 12,200 14C yr B.P. Dwarf shrubs including Salix and Empetrum, and herbaceous plants such as Heracleum lanatum and Hippuris vulgaris, were also important components of the shelf vegetation. Near northern Vancouver Island, mixed coniferous forests dominated by Pinus contorta with Picea, Tsuga spp., Alnus spp., and ferns occupied the shelf at 10,500 14C yr B.P. |
| |
Keywords: | Paleoecology Pollen analysis Continental shelf Late-glacial Paleosols Sea level change British Columbia |
本文献已被 ScienceDirect 等数据库收录! |
|