Multiple-scale interactions structure macroinvertebrate assemblages associated with kelp understory algae

Aim: Kelp forests provide habitat and food that supports a high diversity of flora and fauna. While numerous studies have described macroinvertebrates associated with kelp blades, stipes and holdfasts, a key kelp forest microhabitat, epilithic understory algae, remains poorly studied. Here, we used a macroecological approach and artificial seaweed units (ASUs) to explore the effects of ocean climate, wave exposure and habitat complexity on understory algal associated macroinvertebrate assemblages within Laminaria hyperborea forests in the United Kingdom. Location: 9° latitudinal gradient along the north and west coasts of the United Kingdom. Methods: Replicate ASUs comprising four different habitat complexities were deployed under mature L. hyperborea at 2 sites (along a wave exposure gradient, separated by km) within each of 4 locations (separated by 100s km) nested within two regions (warm and cold, spanning 9° of latitude). After 5 months in situ, the ASUs were collected and macroinvertebrates were identified to species level and enumerated. Results: Habitat complexity and wave exposure both influenced macroinvertebrate assemblage structure, but results also showed clear effects of ocean climate, with macroinvertebrate assemblages differing between warm and cool regions, primarily driven by higher diversity and evenness in the warmer region and greater abundance in the cooler region. Main conclusions: Predicted warming and a shift to less complex turf-forming algal assemblages are likely to alter the structure of macroinvertebrate assemblages associated with understory algae, with potential implications for kelp forest food web dynamics

Inter‐country differences in the cultural ecosystem services provided by cockles

1. Coastal systems provide many cultural ecosystem services (CES) to humans. Fewer studies have focused solely on CES, while those comparing CES across countries are even rarer. In the case of shellfish, considerable ecosystem services focus has been placed on nutrient remediation, with relatively little on the cultural services provided, despite strong historical, cultural, social and economic links between shellfish and coastal communities. The ecosystem services provided by the common cockle, Cerastoderma edule, have recently been described, yet the cultural benefits from cockles remain mostly unknown. 2. Here, we documented the CES provided by C. edule in five maritime countries along the Atlantic coast of western Europe, classifying evidenced examples of services into an a priori framework. The high-level classes, adapted from the Millennium Assessment and the Common International Classification of Ecosystem Services, were: inspirational, sense of place, spiritual & religious, aesthetic, recreation & ecotourism, cultural heritage and educational. A further 19 sub-classes were defined. We followed a narrative approach to draw out commonalities and differences among countries using a semi-quantitative analysis. 3. Examples of CES provided by cockles were found for all classes in most countries. Cockles supply important and diverse cultural benefits to humans across Atlantic Europe, making it an ideal model species to study CES in coastal areas. Most examples were in cultural heritage, highlighting the importance of this class in comparison with classes which typically receive more attention in the literature like recreation or aesthetics. We also found that the cultural associations with cockles differed among countries, including between neighbouring countries that share a strong maritime heritage. The extent to which cultural associations were linked with the present or past also differed among countries, with stronger association with the present in southern countries and with the past in the north. 4. Understanding the wider benefits of cockles could deepen the recognition of this important coastal resource, and contribute to promoting sustainable management practices, through greater engagement with local communities. This study is an important step towards better integration of CES in coastal environments and could be used as a framework to study the CES of other species or ecosystems

Intertidal bathymetry extraction with multispectral images: A logistic regression approach

In this study, a methodology to estimate the intertidal bathymetry from multispectral remote sensing images is presented. The technique is based on the temporal variability of the water and the intertidal zone reflectance and their correlation with the tidal height. The water spectral behavior is characterized by high absorption at the infrared (IR) band or radiation with higher wavelengths. Due to tidal cycles, pixels on the intertidal zone have higher temporal variability on the near IR spectral reflectance. The variability of IR reflectivity in time is modeled through a sigmoid function of three parameters, where the inflection parameter corresponds to the pixel elevation. The methodology was tested at the Tagus river estuary in Lisbon, Portugal, and at the Bijagós archipelago, in the West African nation of Guinea-Bissau. Multispectral images from Sentinel-2 satellites were used, after atmospheric corrections from ACOLITE processor and the derived bathymetric model validated with in situ data. The presented method does not require additional depth data for calibration, and the output can generate intertidal digital elevation models at 10 m spatial resolution, without any manual editing by the operator. The results show a standard deviation of 0.34 m at the Tagus tidal zone, with −0.50 m bias, performing better than the Stumpf ratio transform algorithm, also applied to the test areas to derive intertidal bathymetry. This methodology can be used to update intertidal elevation models with clear benefits to monitoring of intertidal dynamics, morphodynamic modeling, and cartographic update

Navigation Simulator: professional and academic learning tool for the students of the Portuguese Naval Academy

The Portuguese Naval Academy is a military school with an university status and is equipped with one modern navigation and maneuvering simulator. The Navigation Simulator (NAVSIM) plays an essential role in the academic training for the Naval Academy and for its cadets, that are using this capacity since their first academic year as a learning tool. Identifying the non-technical skills that could be trained and focusing on the specific training of the technical skills is paramount, in order to maximize the training sessions for each cadet’s year. The assessment of statistical data referring to the last 6 years is important to identify where there are gaps in the exercises, as well as how the midshipman are prepared to perform functions of watch keeping on the ships fleet

Temporal and spatial drivers of the structure of macroinvertebrate assemblages associated with Laminaria hyperborea detritus in the northeast Atlantic

Kelp forests occur on more than a quarter of the world's coastlines, serving as foundation species supporting high levels of biodiversity. They are also a major source of organic matter in coastal ecosystems, with the majority of primary production released and exported as detritus. Kelp detritus also provides food and shelter for macroinvertebrates, which comprise important components of inshore food-webs. Hitherto, research on kelp detritus-associated macroinvertebrate assemblages remains relatively limited. We quantified spatiotemporal variability in the structure of detritus-associated macroinvertebrate assemblages within Laminaria hyperborea forests and evaluated the influence of putative drivers of the observed variability in assemblages across eight study sites within four regions of the United Kingdom in May and September 2015. We documented 5167 individuals from 106 taxa with Malacostraca, Gastropoda, Isopoda and Bivalvia the most abundant groups sampled. Assemblage structure varied across months, sites, and regions, with highest richness in September compared to May. Many taxa were unique to individual regions, with few documented in all regions. Finally, key drivers of assemblage structure included detritus tissue nitrogen content, depth, sea surface temperature, light intensity, as well as L. hyperborea canopy density and canopy biomass. Despite their dynamic composition and transient existence, accumulations of L. hyperborea detritus represent valuable repositories of biodiversity and represent an additional kelp forest component which influences secondary productivity, and potentially kelp forest food-web dynamic

Spatial variability in the structure of fish assemblages associated with Laminaria hyperborea forests in the NE Atlantic

Understanding fish-habitat associations is critical for ecosystem-based approaches to management and conservation. Kelp species, which are estimated to inhabit around 25% of the world's coastline and underpin highly productive and biodiverse ecosystems, are widely recognised as important nursery and foraging habitats for coastal fish species. However, quantitative assessments of fish assemblages within kelp forests are lacking for many regions. Here, we used Baited Remote Underwater Video (BRUV) and Underwater Visual Census (UVC) to quantify fish assemblages in Laminaria hyperborea forests at eight shallow subtidal rocky reefs that spanned 9° of latitude in the United Kingdom (UK). Fish assemblages were a ubiquitous and conspicuous component of kelp forest communities at all sites. BRUV surveys recorded marked regional-scale variability, with latitudinal shifts in assemblage structure and particularly distinct assemblages recorded in southwest England. These patterns were largely due to greater abundances of Pollachius spp. (i.e. saithe and pollock) in northern regions and higher numbers of Gobiusculus flavescens (two-spotted goby) and labrid species (i.e. rock cook, goldsinny and ballan wrasses) in southern regions. Unlike BRUVs, UVC surveys did not detect significant regional-scale variation in assemblage structure but did detect significant site-level differences, highlighting differences between the two techniques. BRUV surveys also recorded clear latitudinal trends in richness, with more taxa recorded at lower latitudes. Fish assemblages in the NE Atlantic have been, and will continue to be, impacted by ocean warming and fishing activities. Greater spatiotemporal coverage of kelp forest surveys and ongoing robust monitoring is needed to better understand and manage future ecological changes