Caracterización hidrodinámica de praderas naturales de macrófitos bentónicos en fondos someros afectados por mareas

The inner water body of Cadiz bay is a shallow and tide-dominated lagoon, affected by episodic wind-storms and profusely inhabited by marine macrophytes (> 90% covering). These macrophytes are key to the functioning and productivity of this system and their interactions with hydrodynamics affects important ecological processes such as resources uptake and availability, bed stability and sedimentation. To understand the physical settings controlling such processes, the main objective of this PhD thesis was to study the effects of the marine macrophytes on the spatial patterns of current velocity and turbulence, and their potential consequences for sedimentary and nutrients dynamics. For this propose, hydrodynamic gradients along natural canopies, as well as the influence of some benthic landscape elements (i.e. microtopography, benthic transitions and patches fragmentation) were analysed with a combination of in situ measurements (e.g. acoustic Doppler velocimeter (ADV) and dye tracer measurements) and flume tank experiments. Main results revealed that (1) the flow accelerates over the canopies, being partially explained by submergence conditions, (2) fragmentation of intertidal patches augments horizontal turbulent diffusivity of solutes, whereas their retention time remains unaffected, and (3) the leading edge is the most active sedimentation zone on a seagrass meadow. Microtopography seems to promote the benthic macrophyte interactions only on cases affected by high flow events. Overall, diffusive limited- rather than mechanical stress- conditions dominate during no windy spring tide periods. Present study provides important keys to understand the role of marine macrophytes as ecosystem engineers from the inner Cadiz bay.

Author dc:creator

• Lara Rallo, Francisco Miguel

Advisors dc:contributor.advisor

• Pérez Lloréns, José Lucas
• Peralta González, Gloria

• Hydrodynamics
• Seagrass
• Cádiz Bay
• Caulerpa prolifera
• Patchiness
• Microtopography
• Turbulent diffusion
• Sedimentation

Statement dc:rights

• Attribution-NonCommercial-NoDerivatives 4.0 International
• info:eu-repo/semantics/openAccess

Licence dc:rights.uri

• http://creativecommons.org/licenses/by-nc-nd/4.0/

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/10498/16450

OAI identifier oai:identifier

oai:rodin.uca.es:10498/16450