BC3 Seminars: What seaweeds are telling us on climate change?: A view from a local to a European perspective

BC3 Seminars
“What seaweeds are telling us on climate change?: A view from a local to a European perspective “

Prof. Jose M. Gorostiaga
Marine Botanist
Laboratory of Botany,
Faculty of Science and Technology
University of the Basque Country

Abstract

Spatial and temporal changes in marine vegetation along the coasts of southern Bay of Biscay, as a result of both natural and anthropogenic factors (pollution), have been reported in the last century. However, the intensity of these changes in the last 15 years is unprecedented because of its intensity, speed and extent of the geographical area. These recent shifts in macroalgae distributions are attributed to climatic alterations. Ocean warming and acidification are evident effects of the climate change. In the case of the Basque coast, the average summer temperatures of sea-surface water have risen by as much as 1 °C from 1980 to 2008 (20.8 °C to 21.7 °C). No evidence has been found until now that the pH of seawater off Basque coast has varied. However, marine algae have revealed that other environmental factors are involved. Rising solar radiation and decreasing nutrient availability are thought to be factors of change in the distributional pattern of a “key” species of the Basque coastal ecosystem, Gelidium corneum. The stress exerted by the new environmental conditions entails a progressive decline on this red alga which is losing its resilience to other disturbance factors such grazing pressure and storm damage. The rapid response capabilities of the seaweeds to environmental changes makes them ideal organisms for taking the pulse on climate change. Changes in the marine vegetation will have a cascading effect on the coastal ecosystem, with important biological, ecological, and socio-economic consequences, as well as implications for the environmental management policies. For this reason, it is required to address this issue in a multidisciplinary way within a European framework.

Lecturer´s Biodata:

Jose Mª. Gorostiaga is Botany lecturer in the Department of Plant Biology and Ecology at the University of the Basque Country and leader of the Benthic Marine Research Group-UPV/EHU. His research has focused on the effects of human activities on the community structure of marine macroalgae. It has been particularly important the study of the impact of pollution on the functioning of marine benthic communities and the effectiveness of pollution mitigation actions in terms of biological recovery. This research has provide knowledge about the effects of pollution on the structure of benthic communities (Marine Pollution Bulletin; Estuarine, Coastal and Shelf Science), recovery processes models (Marine Ecology Progress Series; European Journal of Phycology; Marine Environmental Research; Marine Pollution Bulletin), sampling optimization (Marine Pollution Bulletin ) and the development of biotic indices for the assessment of the ecological status in compliance with the European Water Framework Directive 2000/60/EC (Ecological Indicators; Hydrobiologia). The background knowledge provided by his research group on natural and degraded communities has made possible to identify more accurately the effects of recent climate alterations on the marine vegetation off the Basque coast (Est. Coast. Shelf Sci., Journal Sea Research).