Trait-based approaches to investigate (short- and long-term) phytoplankton dynamics and community assembly have become increasingly popular in freshwater and marine science. Although the nature of the pelagic habitat and the main phytoplankton taxa and ecology are relatively similar in both marine and freshwater systems, the lines of research have evolved, at least in part, separately. We compare and contrast the approaches adopted in marine and freshwater ecosystems with respect to phytoplankton functional traits. We note differences in study goals relating to functional trait use that assess community assembly and those that relate to ecosystem processes and biogeochemical cycling that affect the type of characteristics assigned as traits to phytoplankton taxa. Specific phytoplankton traits relevant for ecological function are examined in relation to herbivory, amplitude of environmental change and spatial and temporal scales of study. Major differences are identified, including the shorter time scale for regular environmental change in freshwater ecosystems compared to that in the open oceans as well as the type of sampling done by researchers based on site-accessibility. Overall, we encourage researchers to better motivate why they apply trait-based analyses to their studies and to make use of process-driven approaches, which are more common in marine studies. We further propose fully comparative trait studies conducted along the habitat gradient spanning freshwater to brackish to marine systems, or along geographic gradients. Such studies will benefit from the combined strength of both fields.
Farmlands are globally widespread and their management should consider both human and environmental needs. In fact, these man-made ecosystems provide subsistence to the human population but are also habitats for plant and animal communities. The worldwide increase of exotic species has affected native communities, but also human activities or health. We used an exploited farmland in northern Italy, where many exotics are present, as a test case for identifying restoration measures based on an ecosystem approach. In particular, we focused on red swap crayfish for its ecosystem engineering capabilities, and examined the factors affecting its invasion success in order to attempt the definition of management strategies. We used multivariate and regression analysis to evaluate the relationships between the red swamp crayfish, water quality, macrophytes abundance, watercourse hydraulics and the fish community. All analyses indicated that red swamp crayfish was less likely to establish in large, deeper and fast flowing waterways, especially when these are deprived of vegetation and less eutrophicated. Based on our results, fish predation was also a significant factor in limiting red swamp crayfish abundance. We thus concluded that a different hydraulic management, which leaves more water in irrigation canals throughout the winter, could be possibly used to slow down or even reverse the invasion process.
Exposure to oil from the Deepwater Horizon spill may have lasting impacts on preservation of historic shipwrecks in the Gulf of Mexico. Submerged steel structures, including shipwrecks, serve as artificial reefs and become hotspots of biodiversity in the deep sea. Marine biofilms on submerged structures support settlement of micro- and macro-biota and may enhance and protect against corrosion. Disruptions in the local environment, including oil spills, may impact the role that biofilms play in reef preservation. To determine how the Deepwater Horizon spill potentially impacted shipwreck biofilms and the functional roles of the biofilm microbiome, experiments containing carbon steels disks (CSDs) were placed at five historic shipwreck sites located within, and external to the benthic footprint of the Deepwater Horizon spill. The CSDs were incubated for 16 weeks to enable colonization by biofilm-forming microorganisms and to provide time for in situ corrosion to occur. Biofilms from the CSDs, as well as sediment and water microbiomes, were collected and analyzed by 16S rRNA amplicon gene sequencing to describe community composition and determine the source of taxa colonizing biofilms. Biofilm metagenomes were sequenced to compare differential gene abundances at spill-impacted and reference sites. Biofilms were dominated by Zeta-, Alpha-, Epsilon-, and Gamma-proteobacteria. Sequences affiliated with the Mariprofundus and Sulfurimonas genera were prolific, and Roseobacter, and Colwellia genera were also abundant. Analysis of 16S rRNA sequences from sediment, water, and biofilms revealed sediment to be the main known source of taxa to biofilms at impacted sites. Differential gene abundance analysis revealed the two-component response regulator CreC, a gene involved in environmental stress response, to be elevated at reference sites compared to impacted sites within the spill plume fallout area on the seafloor. Genes for chemotaxis, motility, and alcohol dehydrogenases were differentially abundant at reference vs. impacted sites. Metal loss on CSDs was elevated at sites within the spill fallout plume. Time series images reveal that metal loss at a heavily impacted site, the German Submarine U-166, has accelerated since the spill in 2010. This study provides evidence that spill residues on the seafloor may impact biofilm communities and the preservation of historic steel shipwrecks.
Reaching protected area (PA) coverage goals is challenged by a lack of sufficient financial resources. This funding gap is particularly pervasive for marine protected areas (MPAs). It has been suggested that marine conservationists examine examples from terrestrial protected areas (TPAs) for potential solutions to better fund MPAs. However, the funding needs for MPAs and TPAs have not been directly compared, and there is risk of management failures if any such differences are not properly considered when designing MPA financial strategies. We perform an in-depth literature review to investigate differences in distribution of costs incurred by MPAs and TPAs across three primary categories; establishment, operational, and opportunity costs. We use our findings to conduct a snapshot quantitative comparison, which we complement with theoretical support to provide preliminary insight into differences between MPA and TPA costs, and how these may influence financial strategies most appropriate for each type of PA. Our research suggests that TPA costs, and thereby funding requirements, are greater for the time period leading up to and including the implementation phase, whereas MPAs have higher financial requirements for meeting long-term annual operational costs. This may be primarily due to the prevalence of private property rights for terrestrial regions, which are less frequently in place for ocean areas, as well as logistical requirements for enforcement and monitoring in a marine environment. To cement these suggestions in greater analytical certainty, we call for more thorough and standardized PA cost reporting at all stages, especially for MPAs and PAs in developing countries. The quantity and quality of such data presently limits research in PA sustainable finance, and will need to be remedied to advance the field in future years.
Like many other countries, France and Japan now have their own ocean policy, though at different stage of development and in quite different context. On the European side, buzz words like ‘Blue Growth’, ‘Maritime Spatial Planning’, and others, are on the forefront and could make us feel that ocean policies are primarily focused beyond the coast, in offshore waters and their corresponding human activities, somewhat leaving coastal communities in the back seat. Through case studies, we will try to show that ocean policies should be coast-to-coast, across oceans, regional seas, or local well delineated water body, never forgetting that, beyond ‘Blue growth’, we should be heading towards a ‘Blue society’.
Marine protected areas (MPAs) are a common management strategy for conserving marine resources, but it can be challenging to evaluate their effectiveness for meeting management objectives. Measuring the effectiveness of MPAs is particularly challenging in dynamic and changing environments where other management approaches are simultaneously implemented. Before–after–control–impact (BACI) analysis is a tool that offers a simple and robust design for evaluating complex effects. However, design and interpretation of a BACI analysis is not always straightforward. The goal of this study was to explore the potential for BACI to evaluate MPA performance in a system simultaneously impacted by other management measures and environmental change. We develop a typology of interpretations of BACI results based on the main and interaction effects of the model, categorized by the extent to which dynamics inside and outside of the MPA are independent. Furthermore, we examine how decisions about the spatial and temporal design of the study, and the focal species and response variables, can determine which outcomes from within the typology are evident through BACI applications to New England groundfish area closures. We identify strengths and limitations of the BACI approach and demonstrate that BACI is a valuable but imperfect tool for evaluating MPAs.
Restoring degraded peat soils presents an attractive, but largely untested, climate change mitigation approach. Drained peat soils used for agriculture can be large greenhouse gas sources. By restoring subsided peat soils to managed, impounded wetlands, significant agricultural emissions are avoided, and soil carbon can be sequestered and protected. Here, we synthesize 36 site-years of continuous carbon dioxide and methane flux data from a mesonetwork of eddy covariance towers in the Sacramento-San Joaquin Delta in California, USA to compute carbon and greenhouse gas budgets for drained agricultural land uses and compare these to restored deltaic wetlands. We found that restored wetlands effectively sequestered carbon and halted soil carbon loss associated with drained agricultural land uses. Depending on the age and disturbance regime of the restored wetland, many land use conversions from agriculture to restored wetland resulted in emission reductions over a 100-year timescale. With a simple model of radiative forcing and atmospheric lifetimes, we showed that restored wetlands do not begin to accrue greenhouse gas benefits until nearly a half century, and become net sinks from the atmosphere after a century. Due to substantial interannual variability and uncertainty about the multi-decadal successional trajectory of managed, restored wetlands, ongoing ecosystem flux measurements are critical for understanding the long-term impacts of wetland restoration for climate change mitigation.
Ocean acidification (OA), the global decrease in surface water pH from absorption of anthropogenic CO2, may put many marine taxa at risk. However, populations that experience extreme localized conditions, and are adapted to these conditions predicted in the global ocean in 2100, may be more tolerant to future OA. By identifying locally adapted populations, researchers can examine the mechanisms used to cope with decreasing pH. One oceanographic process that influences pH, is wind driven upwelling. Here we compare two Californian populations of the coral Balanophyllia elegans from distinct upwelling regimes, and test their physiological and transcriptomic responses to experimental seawater acidification. We measured respiration rates, protein and lipid content, and gene expression in corals from both populations exposed to pH levels of 7.8 and 7.4 for 29 days. Corals from the population that experiences lower pH due to high upwelling, maintained the same respiration rate throughout the exposure. In contrast, corals from the low upwelling site had reduced respiration rates, protein content, and lipid‐class content at low pH exposure, suggesting they have depleted their energy reserves. Using RNA‐Seq, we found that corals from the high upwelling site upregulated genes involved in calcium ion binding and ion transport, most likely related to pH homeostasis and calcification. In contrast, corals from the low upwelling site downregulated stress response genes at low pH exposure. Divergent population responses to low pH observed in B. elegans highlight the importance of multi‐population studies for predicting a species’ response to future OA.
Marine ecosystem services provide various benefits to people. In order to receive those benefits sustainably, conservation of marine environment is an important measure, and how to motivate people to marine conservation would be one of the keys to secure sustainable receipt of marine ecosystem services. This study explores perception of marine ecosystem services by residents of remote islands, namely Taketomi Town in Japan and how the perception would influence their behavioural intentions for marine conservation. A questionnaire survey was administered to the residents, and factor analysis and Structural Equation Model were applied to analyse data from 344 respondents. The results show that respondents perceive marine ecosystem services in four categories, namely “Benefits closely related to daily lives”, “Benefits from supporting services”, “Benefits from regulating services”, and “Benefits irrelevant to daily lives”. Among the four categories, “Benefits from regulating services” is the most influential to enhance behavioural intentions for marine conservation. The perception of marine ecosystem services by respondents of Taketomi Town and their influence on behavioural intentions for marine conservation are different from the results of previous studies administered to residents in the main island Honshu, Japan. This shows possibility that perception of marine ecosystem services and motivation for behavioural intention for marine conservation would relate to their connectednesspossibility to the sea.
To facilitate the wider implementation of ecosystem modeling platforms and, thereby, to help advance ecosystem-based fisheries management (EBFM) worldwide, tools delivering a large quantity of inputs to ecosystem models are needed. We developed a web application providing OSMOSE ecosystem models with values for trophic, growth and reproduction parameters derived from data from two global information systems (FishBase and SeaLifeBase). Our web application guides the user through simple queries to extract information from FishBase and SeaLifeBase data archives, and it delivers all the configuration files necessary for running an OSMOSE model. Here, we present our web application and demonstrate it for the West Florida Shelf ecosystem. Our software architecture can serve as a basis for designing other advanced web applications using FishBase and SeaLifeBase data in support of EBFM.