The relationship between suspended sediment concentration and sediment deposition within a macro-tidal salt marsh tidal creek system

Abstract

Currently, in Nova Scotia, the primary source of energy comes mainly from carbon-based sources; there is an interest in developing cleaner, local renewable energy sources, such as tidal power in the Bay of Fundy. Our understanding of the impacts of tidal energy extraction on intertidal zones is severely limited. The purpose of this thesis is to examine the sediment dynamics (such as flocculation, role of vegetation, suspended sediment concentration, and deposited sediments) in a salt marsh tidal creek system in the Bay of Fundy. This data will be used in hydrodynamic models currently being developed, to assess the potential impacts of tidal energy extraction on intertidal sedimentation. The experiment took place during the Summer of 2012 through a series of concurrent projects. Suspended sediment concentrations were measured using a stagebottle method at four locations along the Kingsport Marsh, Minas Basin at two elevations (relative to datum) at each site. Sediment concentration was determined using suction filtration. The deposited sediment was measured using three aluminum sediment traps at each of the four locations. All 39 tidal cycles of data were collected during high spring tides. The sites located closest to the creek received the highest amounts of deposited sediment. An increase in the availability of suspended sediment concentration resulted in higher opportunity for the sediment to be deposited on the marsh surface. The results of this study will enhance the knowledge of temporal and spatial influence that sediment dynamics have on the system and will assist in the baseline understanding of tidal power implementation in the Bay of Fundy.