RT doctoral thesis
T1 Influence of leaf traits, hydrodynamics and global change on seagrass-grazer interactions
T2 Influencia de las propiedades foliares, la hidrodinámica y el cambio global en las interacciones entre angiospermas marinas y sus consumidores
A1 Jiménez Ramos, Rocío
A2 Biología
K1 seagrass
K1 plant-herbivore interaction
K1 global change
AB Seagrass-grazer interactions play a fundamental role in ecological processes byregulating structure and functioning of plant communities. Within biotic connections,herbivory is a crucial process because it involves the matter and energy transference fromprimary producers to higher trophic levels, affecting the physical structure of the communityand ecosystem productivity. Contrary to previous beliefs, new insights suggest that grazingmay have an important impact on seagrass communities and that their grazers may be key tounderstand seagrass food webs. Thus, the contrasting response found in previous researchmay indicate that the susceptibility of seagrass species to be grazed may have a temporal andspatial component and even within a community, a preferential consumption of some speciesamong others may exist depending on the palatability of their tissues. Therefore, theassessment of the strength of the seagrass-grazers links and those mechanisms that regulatethis relationship, it is of crucial importance to increase our understanding on community andecosystem structure and dynamics. In addition, it is well known that seagrasses are livingunder local and global threats, and consequently, there is a pressing need to include the globalchange factors (eutrophication, acidification and warming) into the current experimentalapproaches, in order to forecast the future responses of this fundamental community in thechanging world.This PhD Thesis is structured in 6 chapters to answer particular questions aboutseagrass-grazer interactions. In the first two chapters, the importance of hydrodynamics in theseagrass-grazer interactions was studied, and it demonstrated how this abiotic factor acts as atop-down regulator in the community. Moreover, seagrass acclimation to hydrodynamicsmodulates intraspecific seagrass traits, and then seagrass palatability, influencing the selectionof leaves by consumers (chapters 2 and 3). On the other hand, eutrophication and the mainglobal change factors (i.e. warming and acidification) influenced positively Cymodocea nodosapalatability through the alteration of leaf traits and by promoting the growth of epiphytes(chapters 4 and 5). In the last chapter, we looked at the seagrass responses to biomass losspromoted by herbivory, noting how the colonization states influences on thecompensation responses to herbivory in the fast-growing tropical species such as Halodulewrightii.The research presented in this PhD Thesis contributes to identify changes onseagrass palatability under different environmental conditions and global change factors.Particularly, this research displays how hydrodynamics modulate feeding behaviour ofconsumers and how indirect effects of eutrophication and global change enhanceseagrass consumption by herbivores. In addition, this Thesis shows howseagrass colonization states affect to compensatory responses derived by herbivoredamage.The importance of considering biotic processes in conservation and management plans isemphasized in order to enhance seagrass ecosystems resilience and to identify solutions tosupport the maintenance of key ecosystem services provided by seagrass meadows to ourplanet.
YR 2017
FD 2017-10-13
LK http://hdl.handle.net/10498/22831
UL http://hdl.handle.net/10498/22831
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 08-nov-2026