Balanced Sediment Fluxes in Southern California’s Mediterranean-Climate Zone Salt Marshes

• DOI: 10.1007/s12237-015-0056-y
• Publication Date: 2015-12-01T20:47:09Z
• Authors: Jordan A. Rosencranz; Neil K. Ganju; Richard F. Ambrose; Sandra M. Brosnahan; Patrick J. Dickhudt; Glenn R. Guntensp...; Glen M. MacDonald; John Y. Takekawa; Karen M. Thorne
• Keywords: Salt marsh; Sedimentary budget

Salt marsh elevation and geomorphic stability depends on mineral sedimentation. Many Mediterranean-climate salt marshes along southern California, USA coast import sediment during El Niño storm events, but fluxes mechanisms dry weather are potentially important for stability. We calculated tidal creek within a highly modified, sediment-starved, 1.5-km2 (Seal Beach) less modified 1-km2 (Mugu) with fluvial supply. measured plain suspended concentration vertical accretion using single stage samplers marker horizons. At Seal Beach, 2014 yielded 39 28 g/s mean imported 12,000 8800 kg in western eastern channel. Western channel imports offset 8700 exported 2 months of weather, while augmented 9200 weather. During the at Mugu, concentrations increased by factor four; was 1–2 mm near levees. An exceptionally high tide sequence 4.4 flux, importing 1700 kg: 20 % Mugu's fluxes. Overall, low were observed, suggesting that these geomorphically stable conditions. Results suggest storms lunar tides may play large roles, maintaining flux balances California marshes. However, under future climate change sea level rise scenarios, results balanced lead to elevational instability based estimated deficits.