Towards a more sustainable management of temporary rivers: tools for improving their conservation, biomonitoring and social recognition

[eng] Temporary rivers (TRs) are dynamic systems that typically shift between flowing, disconnected-pools and dry phases, and represent nearly 50% of the current global river network. Despite TRs support several unique and endemic aquatic and terrestrial biota, their conservation and management are...

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Detalles Bibliográficos
Autor: Soria Extremera, Maria
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/184843
Acceso en línea:https://hdl.handle.net/2445/184843
http://hdl.handle.net/10803/674027
Access Level:acceso abierto
Palabra clave:Conservació de la diversitat biològica
Invertebrats d'aigua dolça
Ecologia fluvial
Cursos d'aigua
Participació ciutadana
Biodiversity conservation
Freshwater invertebrates
Stream ecology
Rivers
Citizen participation
Descripción
Sumario:[eng] Temporary rivers (TRs) are dynamic systems that typically shift between flowing, disconnected-pools and dry phases, and represent nearly 50% of the current global river network. Despite TRs support several unique and endemic aquatic and terrestrial biota, their conservation and management are still in their infancy compared to perennial rivers. Moreover, in most cases, society seems to hold these rivers in low esteem and they are often associated to environmental degradation. Considering that many perennial rivers are expected to become TRs due to global change, this thesis aims to offer new insights of how conservation and management efforts may best be directed in these ecosystems. Specifically, this thesis aimed to provide an overview on biodiversity in TRs (Chapter 1 and 2), and on how most recent approaches from a research and societal point of view can contribute to their conservation and management (Chapters 2, 3 and 4). This thesis was mainly focused on rivers in the Mediterranean Basin, where TRs constitute one of the predominant freshwater ecosystems. Biodiversity was overall significantly higher in perennial than in TRs worldwide (Chapter 1). Moreover, our findings suggested that if perennial rivers shift to TRs, biodiversity losses may be more important for certain taxonomic groups and under particular environmental conditions. When looking at biodiversity in rivers in the Mediterranean Basin, our results showed that both taxonomic and functional richness were significantly higher in perennial rivers than in TRs (Chapter 2). However, local site contributions to taxonomic and functional β diversity (LCBD) were higher in TRs, especially during the disconnected pools phase, indicating a higher degree of ecological uniqueness of these ecosystems in terms of both species and traits composition. From a management point of view, this thesis showed that current bioassessment methods can produce misleading results when applied to TRs. In contrast, we found that functional metrics were able to detect anthropogenic impacts regardless of natural flow intermittence (Chapter 3). Finally, the thesis also emphasised the implication of citizens into the research, conservation and management of TRs. Involving citizens in the different steps of river conservation and management plans, helped to raise awareness on the biodiversity and ecological value of TRs and to promote stakeholders’ engagement (Chapter 4). Future advances on TR’s conservation and management should (1) consider different components (alpha, beta and gamma) and dimensions (taxonomic and functional) of biodiversity, (2) consider the spatiotemporal variability of biodiversity in conservation management and especially the contribution of TRs in regional biodiversity, (3) develop new metrics to better assess the ecological status of TRs, especially in those less-studied but highly diverse phases, such as disconnected pools, and (4) involve citizens in the different steps of the current conservation and management approaches to promote a coordinated scientific and societal response to future environmental scenarios in TRs. Since Mediterranean-climate regions are considered a global biodiversity hotspot, this thesis contributes to improve and complement current conservation and management practices to halt freshwater biodiversity loss in this region.