Diagnóstico y Caracterización de los Brezales Húmedos (Nat-2000 4020*) de las Sierras Septentrionales de Galicia a partir de Criterios Científicos: Importancia para su Conservación

En el trabajo se realiza una caracterización de las variaciones estacionales de la humedad del sustrato de los brezales húmedos de la Serra do Xistral (Lugo, Galicia), y se compara con la humedad de los diferentes ecosistemas que forman la catena vegetacional en la que se enmarcan, así como con la de otros tipos de humedales estacionales. La representatividad de este territorio ha conllevado su inclusión en la Red Natura 2000, mediante la designación del Lugar de Importancia Comunitaria (LIC) Serra do Xistral (ES1120015). Los datos presentados ponen de manifiesto un funcionamiento ecológico homogéneo de los brezales húmedos en relación al resto del complejo húmedo, así como su funcionamiento inequívoco como ecosistemas húmedos. Por tanto, se confirma el diagnóstico de los brezales húmedos de las Sierras Septentrionales gallegas, vinculados al tipo prioritario Nat-2000 4020*, incluido en el Anexo I de la Directiva Comunitaria 92/43/CEE. El diagnóstico y caracterización de los tipos de hábitat debe considerar la estructura, composición y funcionalidad ecológica, mediante el empleo de conocimientos científicos y técnicos. Esto resulta de vital importancia, sobre todo para la conservación de los tipos prioritarios, evitando la puesta en marcha de planes y proyectos sin una adecuada evaluación de sus repercusionesIn this paper we have performed a characterization of the soil moisture in several wet heaths from Serra do Xistral (Lugo, Galicia), to be compared with that in the different ecosystems existing at the same vegetation catena, as well as other seasonal wetlands in the region. The representativeness of this territory has led to its inclusion in the Natura 2000 network, by designating the Site of Community Importance (SCI) Serra do Xistral (ES1120015). The data presented show a homogeneous ecological functioning of wet heaths in relation to the rest of the wet complex, and sustain their unambiguous operation as wet ecosystems. Therefore, it confirms the diagnosis of wet heaths in the northern mountains of Galicia, linked to priority type Nat-2000 4020*, included in Annex I of the EU Directive 92/43/EEC. The diagnosis and characterization of habitat types should consider the structure, composition and ecological functionality through the use of scientific and technical knowledge. This is of vital importance, particularly for the conservation of priority types, avoiding the implementation of plans and projects without a proper impact assessmentS

Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.Peer reviewe

An UAV and Satellite Multispectral Data Approach to Monitor Water Quality in Small Reservoirs

A multi-sensor and multi-scale monitoring tool for the spatially explicit and periodic monitoring of eutrophication in a small drinking water reservoir is presented. The tool was built with freely available satellite and in situ data combined with Unmanned Aerial Vehicle (UAV)-based technology. The goal is to evaluate the performance of a multi-platform approach for the trophic state monitoring with images obtained with MultiSpectral Sensors on board satellites Sentinel 2 (S2A and S2B), Landsat 8 (L8) and UAV. We assessed the performance of three different sensors (MultiSpectral Instrument (MSI), Operational Land Imager (OLI) and Rededge Micasense) for retrieving the pigment chlorophyll-a (chl-a), as a quantitative descriptor of phytoplankton biomass and trophic level. The study was conducted in a waterbody affected by cyanobacterial blooms, one of the most important eutrophication-derived risks for human health. Different empirical models and band indices were evaluated. Spectral band combinations using red and near-infrared (NIR) bands were the most suitable for retrieving chl-a concentration (especially 2 band algorithm (2BDA), the Surface Algal Bloom Index (SABI) and 3 band algorithm (3BDA)) even though blue and green bands were useful to classify UAV images into two chl-a ranges. The results show a moderately good agreement among the three sensors at different spatial resolutions (10 m., 30 m. and 8 cm.), indicating a high potential for the development of a multi-platform and multi-sensor approach for the eutrophication monitoring of small reservoirsThis research was co-funded by the Spanish Ministry of Research, Innovation and Universities through the Torres Quevedo Sub-Program, grant number PTQ-15-07685S

Diagnóstico y Caracterización de los Brezales Húmedos (Nat-2000 4020*) de las Sierras Septentrionales de Galicia a partir de Criterios Científicos: Importancia para su Conservación

En el trabajo se realiza una caracterización de las variaciones estacionales de la humedad del sustrato de los brezales húmedos de la Serra do Xistral (Lugo, Galicia), y se compara con la humedad de los diferentes ecosistemas que forman la catena vegetacional en la que se enmarcan, así como con la de otros tipos de humedales estacionales. La representatividad de este territorio ha conllevado su inclusión en la Red Natura 2000, mediante la designación del Lugar de Importancia Comunitaria (LIC) Serra do Xistral (ES1120015). Los datos presentados ponen de manifiesto un funcionamiento ecológico homogéneo de los brezales húmedos en relación al resto del complejo húmedo, así como su funcionamiento inequívoco como ecosistemas húmedos. Por tanto, se confirma el diagnóstico de losbrezales húmedos de las Sierras Septentrionales gallegas, vinculados al tipo prioritario Nat-2000 4020*, incluido en el Anexo I de la Directiva Comunitaria 92/43/CEE. El diagnóstico y caracterización de los tipos de hábitat debe considerar la estructura, composición y funcionalidad ecológica, mediante el empleo de conocimientos científicos y técnicos. Esto resulta de vital importancia, sobre todo parala conservación de los tipos prioritarios, evitando la puesta en marcha de planes y proyectos sin una adecuada evaluación de sus repercusiones.In this paper we have performed a characterization of the soil moisture in several wet heaths from Serra do Xistral (Lugo, Galicia), to be compared with that in the different ecosystems existing at the same vegetation catena, as well as other seasonal wetlands in the region. The representativeness of this territory has led to its inclusion in the Natura 2000 network, by designating the Site ofCommunity Importance (SCI) Serra do Xistral (ES1120015). The data presented show a homogeneous ecological functioning of wet heaths in relation to the rest of the wet complex, and sustain their unambiguous operation as wet ecosystems. Therefore, it confirms the diagnosis of wet heaths in the northern mountains of Galicia, linked to priority type Nat-2000 4020*, included in Annex I of the EU Directive 92/43/EEC. The diagnosis and characterization of habitat types should consider the structure, composition and ecological functionality through the use of scientific and technical knowledge. This is of vital importance, particularly for the conservation of priority types, avoiding the implementation of plans and projects without a proper impact assessment

Stratification strength and light climate explain variation in chlorophyll a at the continental scale in a European multilake survey in a heatwave summer

To determine the drivers of phytoplankton biomass, we collected standardized morphometric, physical, and biological data in 230 lakes across the Mediterranean, Continental, and Boreal climatic zones of the European continent. Multilinear regression models tested on this snapshot of mostly eutrophic lakes (median total phosphorus [TP] = 0.06 and total nitrogen [TN] = 0.7 mg L-1), and its subsets (2 depth types and 3 climatic zones), show that light climate and stratification strength were the most significant explanatory variables for chlorophyll a (Chl a) variance. TN was a significant predictor for phytoplankton biomass for shallow and continental lakes, while TP never appeared as an explanatory variable, suggesting that under high TP, light, which partially controls stratification strength, becomes limiting for phytoplankton development. Mediterranean lakes were the warmest yet most weakly stratified and had significantly less Chl a than Boreal lakes, where the temperature anomaly from the long-term average, during a summer heatwave was the highest (+4 degrees C) and showed a significant, exponential relationship with stratification strength. This European survey represents a summer snapshot of phytoplankton biomass and its drivers, and lends support that light and stratification metrics, which are both affected by climate change, are better predictors for phytoplankton biomass in nutrient-rich lakes than nutrient concentrations and surface temperature.Peer reviewe

Stratification strength and light climate explain variation in chlorophyll a at the continental scale in a European multilake survey in a heatwave summer

To determine the drivers of phytoplankton biomass, we collected standardized morphometric, physical, and biological data in 230 lakes across the Mediterranean, Continental, and Boreal climatic zones of the European continent. Multilinear regression models tested on this snapshot of mostly eutrophic lakes (median total phosphorus [TP] = 0.06 and total nitrogen [TN] = 0.7 mg L−1), and its subsets (2 depth types and 3 climatic zones), show that light climate and stratification strength were the most significant explanatory variables for chlorophyll a (Chl a) variance. TN was a significant predictor for phytoplankton biomass for shallow and continental lakes, while TP never appeared as an explanatory variable, suggesting that under high TP, light, which partially controls stratification strength, becomes limiting for phytoplankton development. Mediterranean lakes were the warmest yet most weakly stratified and had significantly less Chl a than Boreal lakes, where the temperature anomaly from the long-term average, during a summer heatwave was the highest (+4°C) and showed a significant, exponential relationship with stratification strength. This European survey represents a summer snapshot of phytoplankton biomass and its drivers, and lends support that light and stratification metrics, which are both affected by climate change, are better predictors for phytoplankton biomass in nutrient-rich lakes than nutrient concentrations and surface temperature

Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains

Data Descriptor: A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins

Under ongoing climate change and increasing anthropogenic activity, which continuously challenge ecosystem resilience, an in-depth understanding of ecological processes is urgently needed. Lakes, as providers of numerous ecosystem services, face multiple stressors that threaten their functioning. Harmful cyanobacterial blooms are a persistent problem resulting from nutrient pollution and climate-change induced stressors, like poor transparency, increased water temperature and enhanced stratification. Consistency in data collection and analysis methods is necessary to achieve fully comparable datasets and for statistical validity, avoiding issues linked to disparate data sources. The European Multi Lake Survey (EMLS) in summer 2015 was an initiative among scientists from 27 countries to collect and analyse lake physical, chemical and biological variables in a fully standardized manner. This database includes in-situ lake variables along with nutrient, pigment and cyanotoxin data of 369 lakes in Europe, which were centrally analysed in dedicated laboratories. Publishing the EMLS methods and dataset might inspire similar initiatives to study across large geographic areas that will contribute to better understanding lake responses in a changing environment