Understanding the Local Drivers of Beta-Diversity Patterns Under Climate Change: The Case of Seaweed Communities in Galicia, North West of the Iberian Peninsula

[Abstract] Aim: To understand spatial-temporal changes (beta-diversity) in coastal communities and their drivers in the context of climate change. Coastal ecosystems are extremely exposed and dynamic, where changes in seaweed assemblages have been associated with changing water temperatures. However, at local scale, the effects of changes in the upwelling events and related stressors seek further exploration. Location: Galicia rías, North West of the Iberian Peninsula. Methods: Using data collected in 42 sampling localities in Galicia rias and over two time periods (1998 and 2014), we analysed changes in the seaweed community's composition through time and space. We calculated the temporal beta-diversity index and spatial beta-diversity as the pairwise composition differences between sampling localities. We use generalized dissimilarity models, to identify local environmental drivers of spatial and temporal beta-diversity. Results: We found a significant change in seaweed communities of Galicia rias, between 1998 and 2014 (temporal beta-diversity). They were mostly related to species loss rather than to species replacement. The dissimilarity among localities (spatial beta-diversity) was significantly higher in 2014 than in 1998. Nitrate concentration was consistently predicted as the main driver of both temporal and spatial beta-diversity patterns. Main conclusions: Unlike other studies in marine ecosystems, our results suggest that observed changes in the structure of perennial seaweed assemblages in Galicia Rias might lead to a local biotic heterogenization, indirectly linked to climate change through changes in nutrients availability and the upwelling intensity. Changes in Galicia seaweed communities call scientific attention to the importance of local stressors in climate change studies.Portugal. Fundação para a Ciência e a Tecnologia; PTDC/BIA-BMA/31893/201

Species composition, distribution, and zonation patterns in the intertidal seaweed assemblages from Santo Antão, Cape Verde

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] Intertidal communities have been extensively studied for decades. Many of these studies have focused on macroalgae, as they are key components of many rocky coastal ecosystems. Despite this, there are still regions of the world where there is a lack of knowledge of intertidal macroalgal communities. This is the case in some tropical regions, such as the Cape Verde archipelago, located on the tropical west coast of Africa. To contribute to the knowledge of the macroalgal communities of this region, during July 2022, we studied the distributional pattern and zonation of macroalgal communities along the rocky intertidal of Santo Antão Island, the northernmost island of the archipelago and the least studied. Using a nested design, we compared the macroalgal assemblages of six rocky shores along the entire coastline, including three sites per shore, and four quadrats per site and tidal level. We found 43 macroalgal species – 29 Rhodophyta, 12 Ochrophyta, 2 Chlorophyta – and one Cyanobacteria. The orders Ceramiales, Corallinales, and Gigartinales were the groups more represented, followed by Ectocarpales and Dictyotales. The upper intertidal was dominated by brown algae, while red algae dominated the middle intertidal. Green algae had a scarce presence in both tidal levels. Our results found no differences between the north and south of the island but between rocky shores and tidal levels. Our results provide for the first time comprehensive information on the seaweed community structure, zonation patterns, and a comparison of seaweed abundances in a vertical and horizontal gradient along the entire rocky shores of Santo Antão Island. In the face of the current climate change, our data can be the baseline for future work on algal communities in this región.Xunta de Galicia; ED481B-2021/095This research was funded by Fundação para a Ciência e a Tecnologia (FCT), Portugal (DivRestore/0006/2020) through the 2020–2021 Biodiversa and Water JPI joint call for research projects, under the BiodivRestore ERA-NET Co-fund, Portugal (GA N◦101003777). MD was supported by a CEEC contract (CEECINST/00027/2021) funded by FCT, Portugal, and MD, FA, and CV were partly funded by UIDB/04423/2020 and UIDP/04423/2020, all through Portuguese national funds, Portugal. CP-C received financial support from Xunta de Galicia ‘‘Axudas de apoio á etapa de formación posdoutoral, ‘‘ Spain (grant ED481B-2021/095)’’. Funding for open access charge by Universidade da Coruña/CISUG

Using citizen science in road surveys for large-scale amphibian monitoring: are biased data representative for species distribution?

Abstract: Road-based citizen science surveys are increasingly used for long-term monitoring of wildlife, including amphibians, over large spatial scales. However, how representative such data are when compared to the actual species distribution remains unclear. Spatial biases in site selection or road network coverage by volunteers could skew results towards more urbanised areas and consequently produce incorrect or partial trend estimations at regional or national scales. Our objective was to compare and verify potential spatial biases of road-based data using distribution datasets of different origins. We used as a case study the common toad (Bufo bufo), a fast-declining species and the main amphibian targeted by conservation action on roads in Europe. We used Maxent models to compare road survey data obtained from the 35 year-long “Toads on Roads” project in Great Britain with models using national-scale toad distribution records as well as with models using randomly generated points on roads. Distribution models that used data collected by volunteers on roads produced similar results to those obtained from overall species distribution, indicating the lack of selection bias and high spatial coverage of volunteer-collected data on roads. Toads were generally absent from mountainous areas and, despite the high availability of potential recorders, showed nearly complete absence of road-based records in large urban areas. This is probably the first study that comparatively evaluates species distribution models created using datasets of different origin in order to verify the influence of potential spatial bias of data collected by volunteers on roads. Large-scale declines of widespread amphibians have been demonstrated using data collected on roads and our results indicate that such data are representative and certainly comparable to other existing datasets. We show that for countries with high road network coverage, such as Great Britain, road-based data collected by volunteers represent a robust dataset and a critical citizen science contribution to conservation

Desert-adapted species are vulnerable to climate change: Insights from the warmest region on Earth

Climate change is eroding biodiversity and conservation efforts have focused on species’ potential responses to those changes. Biological traits associated with sensitivity and adaptive capacities may contribute in identifying a species vulnerability to climate change. Desert-living species could be particularly vulnerable to climate change as they may already live at their physiological limits. This work aims to identify functional groups in Sahara-Sahel endemics, to determine their spatial distribution and to evaluate how the predicted magnitude and velocity of climate change in the region might affect them. We collated biological traits data for all Sahara-Sahel endemics. We then summarized the functional strategy of each species into functional groups with different sensitivities and adaptive capacities to climate change. Future climate scenarios were reclassified to identify areas where predicted temperature and precipitation approach the physiological limits of each group. We calculated the velocity of temperature and precipitation change as the ratio of the temporal gradient to the spatial gradient. Specific magnitudes and velocities of environmental change threaten our seven function groups differently according to their level of exposure and geographical distributions. Groups are more exposed to precipitation than to temperature changes. The more exposed functional groups lived mostly in flat areas, where the predicted magnitude and velocities of change were also the highest. Some functional groups with high adaptive capacities (e.g. volant species) may be able to colonize distinct areas. Other groups with low sensitivity and adaptive capacity (e.g.: ectotherms with small home ranges) may be vulnerable to climate change. Different biological traits contributed to the extent to which climate change harms species. The desert-adapted species may be the most vulnerable ones. The vulnerability patterns of Sahara-Sahel functional groups provide indications of combinations of biological traits and biodiversity’s exposure to climate change in other warm deserts of the world

Using citizen science in road surveys for large-scale amphibian monitoring: are biased data representative for species distribution?

Abstract: Road-based citizen science surveys are increasingly used for long-term monitoring of wildlife, including amphibians, over large spatial scales. However, how representative such data are when compared to the actual species distribution remains unclear. Spatial biases in site selection or road network coverage by volunteers could skew results towards more urbanised areas and consequently produce incorrect or partial trend estimations at regional or national scales. Our objective was to compare and verify potential spatial biases of road-based data using distribution datasets of different origins. We used as a case study the common toad (Bufo bufo), a fast-declining species and the main amphibian targeted by conservation action on roads in Europe. We used Maxent models to compare road survey data obtained from the 35 year-long “Toads on Roads” project in Great Britain with models using national-scale toad distribution records as well as with models using randomly generated points on roads. Distribution models that used data collected by volunteers on roads produced similar results to those obtained from overall species distribution, indicating the lack of selection bias and high spatial coverage of volunteer-collected data on roads. Toads were generally absent from mountainous areas and, despite the high availability of potential recorders, showed nearly complete absence of road-based records in large urban areas. This is probably the first study that comparatively evaluates species distribution models created using datasets of different origin in order to verify the influence of potential spatial bias of data collected by volunteers on roads. Large-scale declines of widespread amphibians have been demonstrated using data collected on roads and our results indicate that such data are representative and certainly comparable to other existing datasets. We show that for countries with high road network coverage, such as Great Britain, road-based data collected by volunteers represent a robust dataset and a critical citizen science contribution to conservation

Using citizen science in road surveys for large-scale amphibian monitoring: are biased data representative for species distribution?

Abstract: Road-based citizen science surveys are increasingly used for long-term monitoring of wildlife, including amphibians, over large spatial scales. However, how representative such data are when compared to the actual species distribution remains unclear. Spatial biases in site selection or road network coverage by volunteers could skew results towards more urbanised areas and consequently produce incorrect or partial trend estimations at regional or national scales. Our objective was to compare and verify potential spatial biases of road-based data using distribution datasets of different origins. We used as a case study the common toad (Bufo bufo), a fast-declining species and the main amphibian targeted by conservation action on roads in Europe. We used Maxent models to compare road survey data obtained from the 35 year-long “Toads on Roads” project in Great Britain with models using national-scale toad distribution records as well as with models using randomly generated points on roads. Distribution models that used data collected by volunteers on roads produced similar results to those obtained from overall species distribution, indicating the lack of selection bias and high spatial coverage of volunteer-collected data on roads. Toads were generally absent from mountainous areas and, despite the high availability of potential recorders, showed nearly complete absence of road-based records in large urban areas. This is probably the first study that comparatively evaluates species distribution models created using datasets of different origin in order to verify the influence of potential spatial bias of data collected by volunteers on roads. Large-scale declines of widespread amphibians have been demonstrated using data collected on roads and our results indicate that such data are representative and certainly comparable to other existing datasets. We show that for countries with high road network coverage, such as Great Britain, road-based data collected by volunteers represent a robust dataset and a critical citizen science contribution to conservation

Overlooked Mountain Rock Pools in Deserts Are Critical Local Hotspots of Biodiversity

<div><p>Background</p><p>The world is undergoing exceptional biodiversity loss. Most conservation efforts target biodiversity hotspots at large scales. Such approach overlooks small-sized local hotspots, which may be rich in endemic and highly threatened species. We explore the importance of mountain rock pools (gueltas) as local biodiversity hotspots in the Sahara-Sahel. Specifically, we considered how many vertebrates (total and endemics) use gueltas, what factors predict species richness, and which gueltas are of most priority for conservation. We expected to provide management recommendations, improve local biodiversity conservation, and simultaneously contribute with a framework for future enhancement of local communities’ economy. The identification of local hotspots of biodiversity is important for revaluating global conservation priorities.</p><p>Methodology/Principal Findings</p><p>We quantified the number of vertebrate species from each taxonomic group and endemics present in 69 gueltas in Mauritania, then compared these with species present in a surrounding area and recorded in the country. We evaluated the predictors of species number’s present in each guelta through a multiple regression model. We ranked gueltas by their priority for conservation taking into account the percentage of endemics and threats to each guelta. Within a mere aggregate extent of 43 ha, gueltas hold about 32% and 78% of the total taxa analysed and endemics of Mauritania, respectively. The number of species present in each guelta increased with the primary productivity and area of gueltas and occurrence of permanent water. Droughts and human activities threaten gueltas, while 64% of them are currently unprotected.</p><p>Conclusion/Significance</p><p>Gueltas are crucial for local biodiversity conservation and human activities. They require urgent management plans in Mauritania’s mountains. They could provide refugia under climate change being important for long-term conservation of Sahara-Sahel biodiversity. Given their disproportional importance in relation to their size, they are local hotspots of biodiversity deserving global attention.</p></div

Priority gueltas for conservation.

<p>A) Ranking of conservation importance of gueltas taking into account the percentage of endemics and threats. Red dots represent priority gueltas for conservation (many endemics and threats); green dots represent important gueltas for conservation (many endemics and few threats) and black dots represent less important gueltas for conservation (few endemics). B) Location of all gueltas coloured by the importance for conservation.</p

Number and percentage of gueltas affected by each threat.

<p>Codes follow the IUCN Threats Classification Scheme [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0118367#pone.0118367.ref030" target="_blank">30</a>].</p><p>Number and percentage of gueltas affected by each threat.</p