Dissertation/ Thesis

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

التفاصيل البيبلوغرافية
العنوان: Caracterización hidrodinámica de praderas naturales de macrófitos bentónicos en fondos someros afectados por mareas
المؤلفون: Lara Rallo, Francisco Miguel
Thesis Advisors: Biología, Pérez Lloréns, José Lucas, Peralta González, Gloria
مصطلحات موضوعية: Hydrodynamics, Seagrass, Cádiz Bay, Caulerpa prolifera, Patchiness, Microtopography, Turbulent diffusion, Sedimentation
الوصف: 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 thissystem 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 ofmarine macrophytes as ecosystem engineers from the inner Cadiz bay.
Description (Translated): Mención europea
نوع الوثيقة: Dissertation/Thesis
اللغة: English
URL الوصول: http://hdl.handle.net/10498/16450
Rights: Consulteu les condicions d'ús d'aquest document en el repositori original:http://hdl.handle.net/10498/16450
رقم الانضمام: edstdx.10803.145305
قاعدة البيانات: TDX