Herbivory effects on the periphytic algae functional diversity: an experimental approach Efeitos de herbivoria sobre a diversidade funcional de algas perifíticas: uma abordagem experimental
UEM
Bárbara Dunck-
[email protected], Ubirajara Lima Fernandes, Diogo Castanho Amaral, Taise Miranda Lopes, Natália Santana, Liliana Rodrigues Programa de Pós-graduação em Ecologia de Ambientes Aquáticos Continentais (PEA), Universidade Estadual de Maringá (UEM), Brasil
Introduction
Data analysis
Herbivory have potential to mediate effects that cascade up and down trophic chains, and is mediated by individual-scale properties of herbivores as feeding mode. Fish and zooplankton have distinct behavior and feeding mode, and are important herbivores of algae community in aquatic ecosystem.
Functional diversity
Functional matrix
mean pairwise distance (MPD)
Size Life forms Adherence Form of adherence
(Webb, 2000)
Goal and hypothesis We tested the main hypothesis that the mixed treatment at the end of the experiment (7 days) present the highest functional diversity of periphytic algae related to the better use of resources by herbivores.
Algal species density
Results
Methods Colonization of periphytic algae
PCA
Colonized glass slides
ANOVA
Nutrients em T2
28 dias 12 Microcosms randomization
One-Way Anova Repeated measures with a betweensubjects factor Factors: Time and treatments
C T3 T2 T1 C T1 C T2 T3 T3
T1
ANOVA
7 days Functional diversity in T3 Species density in T3
T2 Biomass in T2
Treatments
Conclusion Control T1
T3 T2
herbivores Moenkhausia aff. sanctaefilomenae Steindachner 1907
Zooplankton
The highest values of algal densities were related to increased availability of nutrients (T2) and higher algal functional diversity (T3) with complementary use of resources by herbivores. The herbivory acted as density controller in T3 and favored the establishment and development of species with greater diversity of functional characteristics. A possible explanation is that the greater variation in producer species traits can increase the chance of non-edible species or unpalatable to present high diversity.
