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Exacerbated fires in Mediterranean Europe due to anthropogenic warming projected with nonstationary climate-fire models
No full textThe observed trend towards warmer and drier conditions in southern Europe is projected to continue in the next decades, possibly leading to increased risk of large fires. However, an assessment of climate change impacts on fires at and above the 1.5 ?C Paris target is still missing. Here, we estimate future summer burned area in Mediterranean Europe under 1.5, 2, and 3 ?C global warming scenarios, accounting for possible modifications of climate-fire relationships under changed climatic conditions owing to productivity alterations. We found that such modifications could be beneficial, roughly halving the fire-intensifying signals. In any case, the burned area is robustly projected to increase. The higher the warming level is, the larger is the increase of burned area, ranging from ~40% to ~100% across the scenarios. Our results indicate that significant benefits would be obtained if warming were limited to well below 2 ?C
Non-native invasive species as paradoxical ecosystem services in urban conservation education
No full textMany practices have been proposed in conservation education to facilitate a re-connection between nature and the young digital generation in anthropized contexts. In this paper we suggest that, at least in some specific circumstances (urban and suburban areas), non-native invasive species may have a paradoxical and positive impact in conservation education strategies, playing a role as an experiential tool, which represents a cultural ecosystem service, i.e. an ecosystem service that produces cultural benefits by improving pro-environmental behaviours in young people
Life-history strategies in zooplankton promote coexistence of competitors in extreme environments with high metal content
No full textThe toxicity of pollutants on aquatic communities is determined by the specific sensitivities and by the ecological relationships between species, although the role of ecological interactions on the specific sensitivity to pollutants is complex. We tested the effect of exposure to copper on the life-history strategies of two coexisting rotifer species of the genus Brachionus from Inca-Coya lagoon, an isolated water body located in Atacama Desert. The experiments looked at differences in the response to the stress by chemical pollution mimicking field conditions of copper exposure, levels of food, and salinity, between single-species cultures and coexisting species. Under single species cultures, B. \u27Nevada\u27 had lower densities, growth rates, and resting eggs production than B. quadridentatus; when in competition, B. \u27Nevada\u27 performed better than B. quadridentatus in most life-history traits. B. \u27Nevada\u27 was a copper-tolerant species, which outcompeted B. quadridentatus, more copper-sensitive, with higher levels of copper. Species-specific responses to environmental conditions and pollution, plus differential relationships between population density and production of resting eggs, resulted in reduced niche overlap between species, allowing stabilized coexistence. The extreme environmental conditions and the isolation of the Inca-Coya lagoon, make it an excellent model to understand the adaption of aquatic organisms to stressed environments
Fast and automatic data-driven thresholding for inundation mapping with sentinel-2 data
No full textSatellite data offer the opportunity for monitoring the temporal flooding dynamics of seasonal wetlands, a parameter that is essential for the ecosystem services these areas provide. This study introduces an unsupervised approach to estimate the extent of flooded areas in a satellite image relying on the physics of light interaction with water, vegetation and their combination. The approach detects automatically thresholds on the Short-Wave Infrared (SWIR) band and on a Modified-Normalized Difference Vegetation Index (MNDVI), derived from radiometrically-corrected Sentinel-2 data. Then, it combines them in a meaningful way based on a knowledge base coming out of an iterative trial and error process. Classes of interest concern water and non-water areas. The water class is comprised of the open-water and water-vegetation subclasses. In parallel, a supervised approach is implemented mainly for performance comparison reasons. The latter approach performs a random forest classification on a set of bands and indices extracted from Sentinel-2 data. The approaches are able to discriminate the water class in different types of wetlands (marshland, rice-paddies and temporary ponds) existing in the Do?ana Biosphere Reserve study area, located in southwest Spain. Both unsupervised and supervised approaches are examined against validation data derived from Landsat satellite inundation time series maps, generated by the local administration and offered as an online service since 1983. Accuracy assessment metrics show that both approaches have similarly high classification performance (e.g., the combined kappa coefficient of the unsupervised and the supervised approach is 0.8827 and 0.9477, and the combined overall accuracy is 97.71% and 98.95, respectively). The unsupervised approach can be used by non-trained personnel with a potential for transferability to sites of, at least, similar characteristics
Global correlates of diversity in aquatic subterranean fauna
No full textSubterranean aquatic systems are island-like habitats spread all over the world consisting of many caves linked by a common geological history but displaying different ecological parameters (e.g. distance to the sea, topography, depth). Therefore, they comprise numerous, discrete, and varied entities that facilitate independent colonization events by epigean biota, providing many replicates of comparable evolutionary processes. The data produced over the past 100 years of research collectively indicates that subterranean aquatic systems harbor a high percentage of local endemism and disharmonic animal communities when comparing them to surrounding epigean environments. However, it remains unclear whether those are general trends, or whether confounding effects such as sampling bias may produce misleading results. We investigate these two problems by analyzing a global dataset of ca. 50,000 records for ca. 4,000 species in 2,000 caves with two goals. 1. We search for global correlates of diversity in cave aquatic animals by testing the effect of ecological and geological parameters on the number of species, species composition and functional diversity in each cave and subterranean system; 2. We account for the influence of sampling intensity on the analyses by including the number of samples and number of published papers explicitly in the analyses. The highest species diversity was found in the Caribbean and Mediterranean basins: two areas with many caves covering a wide range of ecological conditions, as both basins include marine, anchialine and freshwater subterranean habitats. However, the number of papers per area explained a high proportion of the variation observed of our data, with a taxonomical bias favoring crustaceans. Our results indicate that sampling bias should be carefully considered when drawing conclusions from large-scale analyses, and that we still need further sampling, especially in groups different to crustaceans, to better understand the generality of the processes driving global patterns in subterranean biodiversity
Ecosystem services provided by the bio-physical structure of natural capital in the Danube Delta Biosphere Reserve Romania
No full textThe Danube River is the second largest in Europe and the most international river of the world, before flowing into the Black Sea, it creates a delta covering 5,165 km? that is one of the best preserved in the world. Bio-physical structure of Danube Delta natural capital consist of 38 different ecosystem types supporting a very rich biodiversity area. We matched the ecosystems types to their potential services then ranked them with local, regional and national stakeholders using a participatory GIS approach
Happy birthday Hydrobiologia! 70 years young and still growing?
No full textHydrobiologia started its existence in March 1948 by publishing a first volume of 476 pages, and already then focused on the biology and ecology of aquatic organisms. After 70 years, the focus of the journal is still similar, but the diversity of approaches increased during the seven decades of its existence. To celebrate the 70 years of Hydrobiologia, we here address some emerging trends in the history of publications in Hydrobiologia
Microalgal hydrogen production: achievements and perspectives
No full textHydrogen could be the fuel of the future. Some microorganisms can produce hydrogen upon illumination. Biological methods of production could be greener than chemical or physical production methods, but the potential of biological methods is still being harnessed. This comprehensive book highlights the key steps necessary for future exploitation of solar-light-driven hydrogen production by microalgae. The highly regarded editors bring together 46 contributors from key institutions in order to suggest and examine the most significant issues that must be resolved to achieve the goal of practical implementation, while proposing reliable methodologies and approaches to solve such issues. This 19 chapter book will be an indispensable resource for academics, undergraduate and graduate students, postgraduates and postdoctoral scholars, energy scientists, bio/chemical engineers, and policy makers working across the field of biohydrogen and bioenergy
Towards Global-Scale Seagrass Mapping and Monitoring Using Sentinel-2 on Google Earth Engine: The Case Study of the Aegean and Ionian Seas
No full textSeagrasses are traversing the epoch of intense anthropogenic impacts that significantly decrease their coverage and invaluable ecosystem services, necessitating accurate and adaptable, global-scale mapping and monitoring solutions. Here, we combine the cloud computing power of Google Earth Engine with the freely available Copernicus Sentinel-2 multispectral image archive, image composition, and machine learning approaches to develop a methodological workflow for large-scale, high spatiotemporal mapping and monitoring of seagrass habitats. The present workflow can be easily tuned to space, time and data input; here, we show its potential, mapping 2510.1 km2 of P. oceanica seagrasses in an area of 40,951 km2 between 0 and 40 m of depth in the Aegean and Ionian Seas (Greek territorial waters) after applying support vector machines to a composite of 1045 Sentinel-2 tiles at 10-m resolution. The overall accuracy of P. oceanica seagrass habitats features an overall accuracy of 72% following validation by an independent field data set to reduce bias. We envision that the introduced flexible, time- and cost-efficient cloud-based chain will provide the crucial seasonal to interannual baseline mapping and monitoring of seagrass ecosystems in global scale, resolving gain and loss trends and assisting coastal conservation, management planning, and ultimately climate change mitigation