Name: Vinicius Costa
Type: MSc dissertation
Publication date: 22/02/2019
Advisor:
Name |
Role |
|---|---|
| Frederico Falcão Salles | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| Frederico Falcão Salles | Advisor * |
| Gustavo Rocha Leite | Internal Examiner * |
| Patrik Barcelos e Silva | External Alternate * |
| Roberta Paresque | Internal Alternate * |
| Tathiana Guerra Sobrinho | Co advisor * |
| Walace Pandolpho Kiffer | External Examiner * |
Summary: The objective of this work was to investigate the seasonal fluctuation of
Neotropical Ephemeroptera alates and the processes that determine the order
diversity for the tropical region. The first chapter deals with the investigation of
the seasonal fluctuation of the Ephemeroptera alates in neotropical
environments, we carried out the delineation of the fluctuation of the populations
during the climatic seasons and their relations with the repetitive climatic factors
and the second deals with the ecological aspects of the order and how its diversity
is distributed in the different ecological scales, following the precepts of the
additive partition of diversity. For this we collect data in three streams within the
reserve limits (Lombardy stream, Roda D'água stream and Bragacho stream).
For the phenological data, monthly collections were carried out between May
2017 and April 2018, with light tray traps and malaise traps. To investigate how
factors acting at different spatial scales (local, mesoscale and regional) influence
diversity. A campaign of nymphs collection in 18 points was carried out, being six
points in each stream studied, the sampling was performed by the sweep method.
Both carried out in the Augusto Ruschi Biological Reserve, located in the
municipality of Santa Teresa ES. In this way, the collections were performed
according to the following hierarchical scheme: (α) covering only the substrate
(litter, stone and gravel/sand); (β1) differences between species composition
between sites; (β2) meso-habitats, which comprises the species exchange that
occurs between the substrates plus the velocity of the water flow (backwater or
stream); (β3) exchange between species composition between streams and (γ)
the regional diversity sum of all hierarchical levels. A total of 1676 Ephemeroptera
alates belonging to five families were collected. 403 specimens of
Ephemeroptera nymphs, five families and 24 species. The data presented and
discussed in this study corroborate the hypothesis that Ephemeroptera order of
the Neotropical region presents a seasonal pattern of abundance and wealth
during the year. Most species of Ephemeroptera have greater abundance
between November and February. This seasonal pattern is a reflection of the
seasonal differences in the cyclical temperature and rainfall regimes of the
studied landscape. However, as seen, this behavior can not be explained only by
climatic factors. The most abundant families of the landscape seem to show
differentiation in the period of flight. We also verified that at the micro-habitat level
the type of substrate exerts a great influence on the wealth and abundance rates
of the Ephemeroptera community. At the landscape level, however, the local
hierarchical level contributes least to the determination of diversity. The
differences between the rivers, in this way, is the most important factor for the
increase of species to the regional diversity. That is, this result is particularly
relevant for programs conservation appeal. Thus, resource spending on diversity
studies and biodiversity conservation programs of the studied fauna may be more effective in prioritizing (i) large spatial coverage and (ii) diversity of substrates.
