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dc.contributor.authorViggato, Tammyen_US
dc.date.accessioned2016-01-25T19:28:53Z
dc.date.issued2013
dc.identifier.urihttps://hdl.handle.net/2144/14081
dc.description.abstractLarge areas of mesotidal estuaries become subaerial during low tide. Here we study the effect of nutrient enrichment and several meteorological and hydrodynamic parameters on the erodability of mudflat substrates when they are emergent. We tested the impact of nutrient fertilization on tidal flat sediments over a two week period in September 2011 in Plum Island Sound, Massachusetts (USA). High resolution measurements from our experiment indicate that daily nutrient enrichment at 70 μM NO3‾ using our experimental approach does not change the critical shear stress of the muddy substrate, nor affect the concentration of chlorophyll a at the surface. Sediment erodability is instead directly related to the potential evaporation rate and to the duration of the subaerial period. Chlorophyll a concentration decreases when evaporation is high, possibly due to the downward migration of diatoms. Sediment concentrations in the water column during submergence strongly depend on bottom shear stresses triggered by tidal currents. Surprisingly, they are also related to the total evaporation that occurred in the previous emergence period. We conclude that subaerial desiccation at low tide decreases the erodability of mudflat sediments. This strengthening effect is not lost during the following submerged period, thus limiting the erosive effect of tidal currents. For the first time we show that not only subaqueous but also subaerial processes control the erodability of mudflats. Global warming and other climatic variations regulating long-term evaporation rates can therefore directly affect the stability of mudflats in mesotidal environments.en_US
dc.language.isoen_US
dc.subjectEnvironmental scienceen_US
dc.subjectBiofilmen_US
dc.subjectErosionen_US
dc.subjectEvaporationen_US
dc.subjectHydrodynamicen_US
dc.subjectMudflatsen_US
dc.subjectSedimenten_US
dc.titleThe effect of evaporation and nutrient enrichment on the erodability of mudflats in a mesotidal estuaryen_US
dc.typeThesis/Dissertationen_US
dc.date.updated2016-01-22T18:53:36Z
etd.degree.nameM.A.en_US
etd.degree.levelmastersen_US
etd.degree.disciplineEarth Sciencesen_US
etd.degree.grantorBoston Universityen_US


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