Freshwater ecosystems are relevant components in the global C cycle. Throughout its passage towards the ocean, C can be buried in the sediments or emitted as CO2 or CH4, altering the distribution of C sinks in continents. Most of the processes modulating these fluxes are vulnerable to the ongoing environmental changes (e.g.damming and morphological alterations, eutrophication, land use changes, extreme events and temperature increases), and therefore, changes on them have the potential to affect the C cycling in freshwater ecosystems.
This session aims to advance on the comprehension of the effects of these changes on the freshwater C cycling, taking into account the different ecosystem facets (physical, chemical or biological) that can be impacted. We invite presentations on research assessing changes in any aspect of the aquatic C cycle, from compositional changes in DOM, to GHG emissions or changes in metabolic responses. Contributions taking into account future perspectives and projected changes are particularly welcome.
This special session will be devoted to large branchiopods, with particular focus on species distribution in the Iberian Peninsula, and conservation issues. Large branchiopods are a group of crustaceans that almost exclusively inhabit temporary ponds, and are often considered a flagship group of invertebrates of these habitats. Species richness is high in the Mediterranean Basin, with 47 species recorded according to the recent review on invertebrates in freshwater wetlands (edited by Batzer & Boix, and soon to be published). The proportion of endemic species reaches 55% as they represent an example of faunal complexes persisting over millennia with many local adaptations. Their vulnerability to predation can explain their isolation to ephemeral habitats and thus, they have been regarded as sentinel species of the impact of exotic species, such as the red-swamp crayfish. There is also an increasing number of publications suggesting that large branchiopods play a pivotal role in the trophic structure and microcrustacean assemblages of ephemeral aquatic habitats. This close relationship between large branchiopods and temporary ponds generates many interesting issues regarding the conservation of these habitats and the species therein. For example, the most critically endangered aquatic animal species in Andalusia is an anostracan (Linderiella baetica n. sp) that has been reported to inhabit a single temporary freshwater pond that is currently unprotected. In Mediterranean regions, temporary ponds are a priority habitat to be preserved though they are defined by particular vegetation communities according to the European Habitats Directive. The scarce knowledge on the ecology and distribution of large branchiopods may have limited the use of this group in protection policy, but this situation may be reversed in view of the increasing number of publications (a fifth of all SCI papers on large branchiopods have been published since 2014), and this special session may contribute to that change.
Laura Serrano (Plant Biology and Ecology Department, University of Sevilla), Faculty of Biology, Sevilla, Spain.
Last October 15th, our friend, colleague, and mentor Maria Rieradevall passed away. Maria was a very versatile researcher who helped to advance the knowledge of Iberian limnology. She started her studies analysing Chironomidae exuviae from the Llobregat River, and soon after began her PhD thesis about the benthos of the Banyoles Lake under the supervision of Prof. Dr. Narcís Prat. She continued her research working on the taxonomy of Chironomidae and the study of the ecology of Mediterranean rivers. More recently, she focused on intermittent rivers in the Iberian Peninsula, being one of the first to consider the joint effect of drought and fire on aquatic macroinvertebrates. She was also involved in several projects to design biomonitoring tools to assess the ecological status of Mediterranean and Andean rivers. She always kept her interest in lentic environments, especially in coastal lagoons and mountain lakes. Her experience on Chironomidae communities was very valuable when studying paleolimnological records to explore the past to understand the present. Along her research career, she supervised 23 Bachelor/Master, 5 PhD, and 2 ongoing PhD theses and trained a generation of very enthusiastic researchers who are following her paths. She will be remembered by her contributions to the Iberian limnology but also by her passion for docent activities, scientific outreach, and her rigour and creativity in whatever she was involved.
This special session aimed at paying tribute to Maria by presenting different works related with her research interests, including the different topics mentioned above and some of the works that, unfortunately, she could not see completed. It is also our aim that this special session will be an open forum and a nice opportunity for anybody who wants to pay their particular tribute to Maria.
F.E.M. (Freshwater Ecology and Management) members, Department of Ecology, University of Barcelona, Avda. Diagonal 643, 08028 BARCELONA (Catalonia/Spain).
In recent years community ecology has undergone a clear transformation, from a discipline largely focused on the influence of local processes to a discipline encompassing much richer fields of study. These include the linkages between communities separated in space (metacommunity dynamics), the relative role of niche and neutral processes, the interplay between ecology and evolution, and specially the influence of historical and regional processes in shaping patterns of biodiversity at wider spatial scales. From a more applied perspective, there is also a new tendency trying to improve the methods to detect, assess, and predict the impacts of multiple stressors on biological communities. This is especially relevant in Mediterranean ecosystems, where multiple natural (e.g. drought, salinity, fire) and anthropogenic pressures usually co-occur and interact.
Although most of these theoretical and applied advances in community ecology have been developed in terrestrial ecosystems, a number of freshwater ecologists are already working on these topics, integrating taxonomy, phylogeny, functional traits, species interactions, and environmental conditions and pressures as potential determinants of biological communities. In this special session we will cover these advances in community ecology considering the following four major themes:
The final aim of this session is to provide a broad appreciation of current advances in community ecology in freshwaters. Thus, particular emphasis will be placed on works focusing on observational and experimental supporting (or not) the principal community ecology theories.
In the last decade research on transitional waters in Europe has speed up mostly due to the unfolding of the Water Framework Directive. Although this research has been mostly applied to the development of ecological indicators to assess the status of water bodies, the acquired data have also given the opportunity to deepen in the ecological functioning of many types of aquatic ecosystems at the crossroad between continental and marine systems, such as coastal lagoons, bays, deltas, estuaries and marshes. This special session will cover research on transitional waters aiming to integrate the applied field of ecological indicators with other related fundamental fields such as community ecology, functional ecology and theoretical ecology.
In addition this special session will show results of current research carried out in the main estuarine systems (especially the Ebro Delta) and discuss how this research can be applied in terms of environmental management tools. We particularly invite contributions showing studies of ecological status and ecosystem processes to assess current impacts and future changes in different transitional environments.
The subsidy-stress hypothesis (Odum et al. 1979) states that some stressors always produce detrimental effects on the biota, whereas others can subsidize biological activity at low to moderate intensities, whereas they suppress it at high intensities. This hypothesis has been tested with single stressors, but there is little information on multi-stress situations as those currently faced by most freshwater ecosystems as a consequence of global environmental change. In this session we seek for research on freshwater organisms, communities or ecosystem processes that addresses the response of biological activity to a range of multiple stressors on the light of the subsidy-stress hypothesis. Redefining this hypothesis and understanding the response or river ecosystems to multiple stress can increase current understanding on the consequences of environmental change, improve our capacity to conserve and restore freshwater ecosystems, and promote the optimization of associated ecosystem services.
Freshwater ecosystems are experiencing major biodiversity losses during the last decades, mainly due to different aspects associated with global change. The introduction of alien species is one of the main factors causing these profound ecological changes. The Iberian Peninsula is not exempt of these threats and although few invasions have been extensively documented there are new invasions taking place threatening poorly studied areas. Alien introduced species include species from different groups, such as aquatic plants, fishes, amphibians, molluscs, crustaceans, etc. Invasions are causing many socio-ecologic conflicts and major economic losses and the lower Ebro river and its delta is an unfortunate good example of it. Conservation management has to face the consequences of the arrival of new species, especially those that take a strong role in structuring ecosystems. To be able to develop correct management policies is basic to know in detail the impact of introduced species and their role in the ecosystem. This special session will be devoted to document the conservation status of freshwater aquatic ecosystems related with the introduction of alien species both their process of introduction and their known ecological consequences. Results of conservation projects aiming to improve the impact of aliens in freshwater ecosystems are welcomed.
Marc Ventura-1, Esperança Gacia-1, Quim Pou-Rovira-2