Banca de QUALIFICAÇÃO: ALESSANDRA PASIAN LONARDONI

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : ALESSANDRA PASIAN LONARDONI
DATE: 05/05/2023
TIME: 14:00
LOCAL: Ambiente virtual
TITLE:

Fish abundance and their traits revealed by Amazon types of water

PAGES: 51
BIG AREA: Ciências Biológicas
AREA: Ecologia
SUBÁREA: Ecologia de Ecossistemas
SUMMARY:

Ecological studies investigate factors influencing biodiversity, community structure, species distribution, and abundance. These factors include interactions with environmental conditions, so our main objective was to assess how different types of water found in the Amazon influence the total abundance and functional composition of fish assemblages. For this, we built an extensive database gathering experimental collections of fish, carried out only with gill nets. For the most part, these data were provided by partners who regularly carry out standardized sampling of fish in the region. Thus, the database comprises 199 georeferenced sampling points with information on the hydrological period, the type of water in the main basin (white, clear, or black), and taxonomic information on the fish. The taxonomic validity of each record was assessed and corrected according to Eschmeyer's Catalog of Fishes Online Database and experts. Chapter 1 consists of a database that will be submitted for publication to offer data on fish abundance to the scientific community, collaborating with the investigation of patterns and processes that act in the Amazonian diversity, in addition to valuing the work of decades of expeditions in the Amazonian rivers. In Chapter 2 we assessed how fish communities are structured. For this, we selected all floodplain lakes that had collections in the hydrological periods of ebb, low water, and flood (85 sample points). We selected environmental variables at the watershed scale to investigate the influence of energy and habitat predictors on the total abundance and functional composition of assemblages. Our results bring evidence that energy is the main factor that operates in the structuring of fish assemblages in the Amazon and that the different types of water act as filters by selecting different functional attributes in each of them. Our results show that in white water environments, there is a greater total abundance when compared to black water environments. White and clear water environments support the dominance of piscivorous species, as they have the high energy needed to sustain many piscivores at the top of the aquatic food web. White water environments predominantly have species with a seasonal reproductive strategy and large sizes (>15cm), which is expected for seasonal environments such as lowland lakes that flood periodically with the increase in river level during periods of flooding and flooding. Clear water environments are predominantly inhabited by species with a balanced reproductive strategy, which is related to the presence of large eggs, in low numbers, and care for the offspring. Finally, black water environments presented, predominantly, a high number of species whose strategy is seasonal reproductive with small sizes (< 15cm). This life history strategy indicates that the low energy available in this system sustains a large number of fish in different trophic levels and, mainly, smaller maturation sizes than in other environments with different types of water. Water types are therefore important environmental filters that, over evolutionary time, select life history strategies according to several factors, including the productivity of each system.

COMMITTEE MEMBERS:
Presidente - Interno ao Programa - 149.309.488-27 - GISLENE TORRENTE VILARA - UFABC
Membro Titular - Examinador(a) Interno ao Programa - 1154247 - FABIANA RODRIGUES COSTA NUNES
Membro Titular - Examinador(a) Externo à Instituição - LIS STEGMANN
Membro Suplente - Examinador(a) Interno ao Programa - 1804548 - RICARDO JANNINI SAWAYA
Membro Suplente - Examinador(a) Externo à Instituição - NARAIANA BENONE