Caring about the future

BenthicLink – Trophic links regulated by tidal and daily rhythms: benthic microflora and fauna in estUAries
Coordinator - Henrique Queiroga
Programme - POCI
Execution dates - 2005-07-01 - 2008-06-30 (36 Months)
Funding Entity - FTC
Funding for CESAM - 81200 €
Total Funding - 89000 €
Proponent Institution - Universidade de Aveiro
Participating Institutions
Instituto de Oceanografia

Project Description

The BenthicLink project concerns the influence of the tidal and the diel cycles on the grazing of microphytobenthos by macrofauna in estuaries and coastal lagoons. In these ecosystems tidal flats represent a large proportion of the total area, and microphytobenthos represents therefore an important source of organic matter, accounting for up to 50% of total primary production. A large, but unknown, part of this production is consumed by grazers of the macrofauna, which channel this production to the higher trophic levels. The project will use microphytobenthos and the gastropod Hydrobia ulvae as a biological model to address the following questions: 1. How is vertical migration and production of microphytobenthos controlled by tidal exposure, irradiance and water content of the sediment? 2. How is rhythmic crawling and feeding activities of Hydrobia controlled by the presence of microphytobenthos, tidal exposure, light/dark cycles and water content of the sediment? 3. Is the periodic increase of microphytobenthos biomass at the surface of the sediment, on a daily time scale, reflected in an increase of ingestion and assimilation by Hydrobia? 4. Is the periodic increase of microphytobenthos biomass at the surface of the sediment, on a semilunar time scale, reflected in an increase of ingestion and assimilation by Hydrobia? The BenthicLink project will use video recording and automated image analysis for the description of feeding behaviour of Hydrobia, PAM fluorescence for the study of migratory rhythms of microphytobenthos, 14C labelling for the measurement of ingested and assimilated carbon by Hydrobia, and HPLC for the determination of degradation products of chlorophyll a in the faeces of Hydrobia. The ratio of assimilated microphytobenthos carbon to the degradation products will be used to estimate assimilation in the natural environment and, therefore, the ecological efficiency and the absolute energy transfer at the microphytobenthos/Hydrobia link.



Project webpage
http://sweet.ua.pt/~f461/

CESAM members on this project
Henrique Queiroga
Coordinator

CESAM Funding: UIDP/50017/2020 + UIDB/50017/2020 + LA/P/0094/2020