Document type
Conference papers
Document subtype
Abstract
Title
Scale effects on food-web indicators -impacts at Biogeographic Region level
Participants in the publication
Inês Machado (Author)
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
José Lino Costa (Author)
Dep. Biologia Animal
MARE
Célia M. Teixeira (Author)
MARE
Henrique Cabral (Author)
MARE
Summary
The development and operationalization of Food-web indicators Descriptor 4 - Food-webs) in the MSFD context faces several difficulties, such as: lack of data for relevant taxa, absence of fully operational indicators, spatially and temporally limited datasets. This work aims to improve methodologies used to assess Food-webs by identifying relevant scales for Food-web evaluation while assessing the effects of scales on GES. With focus on four indicators, developed to detect fishing pressure on food-webs - MTL, MTI, LFI and MATG - seven spatial and four temporal ranges were tested, using groundfish survey data for two Biogeographic Regions. Spatial scales were a major source of variability when compared to temporal ones. MTL and MTI (TL>3.25) results were not affected by temporal and spatial variability. MTI (TL>4) and LFI were largely explained by spatial scales, requiring more detailed scales: MTI deviance was significantly explained by ICES Rectangles while LFI by Sector/ Strata. Temporal scales explained low values of deviance for both indicators. Higher TL thresholds (TL>4) required the use of more detailed scales as communities analysed were narrower and variability increased. MATG was explained by bi-annually datasets and Sector/Strata, but deviance explained was low. Bay of Biscay and Iberian Coast data was more variability than Celtic Seas, requiring smaller size scales. To accurately extract ecosystem indicators variability, further effort is required from MSs to downsize spatial scales addressed and from the EC to improve standardization. This study identifies scales that further explain variability, improving indicators capability to distinguish natural variability from anthropogenic effects.
Date of Submisson/Request
2019-05
Date of Acceptance
2019-06
Date of Publication
2019-08
Institution
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
Event
15th European Ecological Federation (EEF) Congress and 18th National SPECO Meeting
Publication Identifiers
Address
Lisbon
Organizers
SPECO
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