Banca de DEFESA: RODRIGO MOSQUERA TANASOVICI

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : RODRIGO MOSQUERA TANASOVICI
DATA : 17/02/2022
HORA: 10:00
LOCAL: Remota https://meet.google.com/kkq-azoy-shv
TÍTULO:

How coastal constructions and the proximity to the soft bottom affect the dynamics of the encrusting community?

PÁGINAS: 58
GRANDE ÁREA: Ciências Biológicas
ÁREA: Ecologia
RESUMO:

Coastal constructions affect marine biodiversity by increasing substrate availability, pollutants concentration, besides modifying local hydrodynamics. These conditions restrict species that could recruit and survive, and then marinas and ports support a community that is distinct from natural substrates nearby, presenting a high abundance of non-indigenous species (NIS). These NIS populations produce reproductive propagules that could affect the dynamics of natural habitats nearby, however, the intense water circulation, predation pressure and lower pollutant concentration in natural habitats could represent a mechanism of NIS resistance. Part of these differences could be result of the distance from the seafloor, once the communities developing in artificial substrates are usually suspended and distant from the soft bottom, which doesn’t represent what happens in rocky shores, where sedimentation rates and predation by benthic organisms, such as crabs and gastropods can be high. This way, in this project I analyzed the difference between communities that developed near the seafloor and in the water column in two natural habitats, to verify whether the position where the communities developed (water column vs. seafloor) influence the structure of communities. Furthermore, I analyzed how the proximity to coastal constructions affect the structure and composition of fouling communities. To do that, we installed PVC plates as substrates for communities in two marinas and two rocky shores in the São Sebastião channel – SP. In each location, samples were divided in three treatments: communities protected against predation using a plastic mesh; manipulation control using a fence; and communities exposed to predators. After 18 months, the plates were weighted and photographed, and total, native and exotic richness, bare space and the cover of native and exotic were estimated. We analyzed how predation, proximity to constructions and the position in the water column affected the community structure. In general, most of the metrics were affected by local factors, however, communities that developed in the water column were different from the ones developing near the seafloor, with a higher coverage of the exotic bryozoan Schizoporella errata in the water column and a higher coverage of the native Amathia brasilienis, the native sponge Mycale angulosa and the cryptogenic bryozoan Hipopodina feegensis, when near the seafloor. On the other hand, artificial environments showed higher total richness than natural habitats, resulting from a higher number of exotic species. Independently of the proximity to coastal constructions, predation determined the community structure and, on some sites, it reduced the diversity of native species and favored communities dominated by organisms with structural defenses. While my work reinforces the importance of predation independently of the proximity to coastal constructions, a higher richness of exotic organisms in artificial environments is a reflex of the biotic homogenization between such locations, possibly due to predation on native species and this represents a potential risk to nearby natural locations.

MEMBROS DA BANCA:
Presidente - Interno ao Programa - 1768895 - GUSTAVO MUNIZ DIAS
Membro Titular - Examinador(a) Externo à Instituição - ANGELO FRAGA BERNARDINO - UFES
Membro Titular - Examinador(a) Externo à Instituição - IGNACIO GESTOSO - Cádiz
Membro Suplente - Examinador(a) Interno ao Programa - 1762351 - NATALIA PIRANI GHILARDI LOPES
Membro Suplente - Examinador(a) Externo à Instituição - EDSON APARECIDO VIEIRA FILHO - UFRN