Factors affecting seasonality of lithogenic and biogenic particle flux in a large estuarine ecosystem |
| |
| Authors: | BT Hargrave GL Bugden EJH Head B Petrie GA Phillips DV Subba Rao PA Yeats |
| |
| Institution: | aDepartment of Fisheries and Oceans, Ecosystem Research Division, 1 Challenger Drive, Dartmouth, NS B2Y 4A2, Canada;bDepartment of Fisheries and Oceans, Ocean Science Division, Dartmouth, NS B2Y 4A2, Canada |
| |
| Abstract: | Seasonal patterns of vertical flux over two years (2001–2003) at two stations in the Bras d'Or Lakes, a large estuary in Cape Breton Island, Nova Scotia, were determined using aluminum and organic carbon in settled particles collected in moored traps to calculate lithogenic (terrigenous) and marine biogenic fractions. On an annual basis, lithogenic material comprised 53% and 81% of dry weight and 48% and 66% of organic carbon in settled particles at the deep- (128 m) and shallow-water (41 m) locations, respectively. Peaks in runoff, inferred from rain and snowfall precipitation, ice cover and possible horizontal transport of resuspended sediment coincided with maximum sedimentation rates of lithogenic material during unstratified periods between October and March. Biological factors correlated with phytoplankton and ice algal primary production and seasonal changes in zooplankton grazing inferred from phaeopigments controlled biogenic particle fluxes under stratified conditions between June and September and during winter. Year-to-year variations in deposition of lithogenic and marine biogenic material depended on seasonal differences in stratification, precipitation, freeze/melt conditions and the extent of ice cover. |
| |
| Keywords: | sedimentation organic carbon nitrogen aluminum silicon opal chloropigments Bras d'Or Lakes Nova Scotia |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
