Coastal areas are especially important to human well-being with half the world's population living within 60 km of the sea and three-quarters of all large cities located in the coastal zone. Supporting and regulatory ecosystem services in coastal areas have received considerable research attention given human vulnerability to climate change, but cultural ecosystem services in the coastal zone are less understood. This study describes and analyzes the distribution of cultural ecosystem values found in coastal areas in multiple countries (n = 5) and compares the results with non-coastal areas. Mapped cultural ecosystem values were collected from public participation GIS (PPGIS) processes in the U.S., Australia, New Zealand, Norway, and Malaysia and analyzed to identify the type and intensity of ecosystem values located in coastal areas. Mapped ecosystem values were significantly more abundant in all coastal zones, regardless of ecosystem value category, country, population, or dominant land use. Compared to cultural ecosystem values, biological and life-sustaining values were mapped less frequently in the coastal zone. Economic and social values were significantly associated with developed (built) coastal zones, while aesthetic and recreation values were more strongly associated with natural coastal zones. Coastal access, especially by road, influences the mix of perceived values from nature-based values to anthropocentric values. Coastal zones will continue to be the principle location for potential future land use conflict given their high social and cultural value relative to other ecological values. Understanding trade-offs in coastal zone planning and management requires a systematic inventory of the full range of ecosystem services, including cultural services.
Coral reefs are responsible for a wide array of ecosystem services including shoreline protection. However, the processes involved in delivering this particular service have not been fully understood. The objective of the present review was to compile the main results in the literature regarding the study of shoreline protection delivered by coral reefs, identifying the main threats climate change imposes to the service, and discuss mitigation and recovery strategies that can and have been applied to these ecosystems. While different zones of a reef have been associated with different levels of wave energy and wave height attenuation, more information is still needed regarding the capacity of different reef morphologies to deliver shoreline protection. Moreover, the synergy between the main threats imposed by climate change to coral reefs has also not been thoroughly investigated. Recovery strategies are being tested and while there are numerous mitigation options, the challenge remains as to how to implement them and monitor their efficacy.
The EU Blue Growth Agenda targets maritime economic activities that have the sea and the coasts as drivers. These activities are supported by marine Ecosystem Services (ES) in combination, or not, with abiotic outputs from the marine natural capital. This paper analyses Blue Growth activities with regards to the demand and supply of marine ES and Good Environmental Status (GES). The results show that marine provisioning ES support aquaculture and blue biotechnology, while blue energy is supported by marine provisioning ES and by abiotic provisioning, and abiotic provisioning supports extraction of marine mineral resources. Maritime, coastal and cruise tourism is supported by cultural marine ES and cultural settings dependent on marine abiotic structures. All these multi-sectoral economic activities depend on healthy marine and coastal ecosystems that are provided by regulating and maintenance ES combined with the abiotic regulation and maintenance by natural marine physical structures and processes. In order to balance concurrent sectoral interests and achieve sustainable use of marine resources there is the need to consider indicators for demand for ES, which are social and economically driven, and for the supply, which are dependent on ecosystems capacity to provide the required marine ES. Some of the actions foreseeing GES are already anticipated in legislation that underpin Blue Growth, whilst others could benefit from additional regulation, particularly in what concern the exploration and exploitation of marine mineral and biological resources. Blue Growth options require navigating trade-offs between economic, social and environmental aspects.
Changes in the Earth's environment are now sufficiently complex that our ability to forecast the emergent ecological consequences of ocean acidification (OA) is limited. Such projections are challenging because the effects of OA may be enhanced, reduced or even reversed by other environmental stressors or interactions among species. Despite an increasing emphasis on multifactor and multispecies studies in global change biology, our ability to forecast outcomes at higher levels of organization remains low. Much of our failure lies in a poor mechanistic understanding of nonlinear responses, a lack of specificity regarding the levels of organization at which interactions can arise, and an incomplete appreciation for linkages across these levels. To move forward, we need to fully embrace interactions. Mechanistic studies on physiological processes and individual performance in response to OA must be complemented by work on population and community dynamics. We must also increase our understanding of how linkages and feedback among multiple environmental stressors and levels of organization can generate nonlinear responses to OA. This will not be a simple undertaking, but advances are of the utmost importance as we attempt to mitigate the effects of ongoing global change.
Sharks play a key role in the structure of marine food webs, but are facing major threats due to overfishing and habitat degradation. Although sharks are also assumed to be at relatively high risk from climate change due to a low intrinsic rate of population growth and slow rates of evolution, ocean acidification (OA) has not, until recently, been considered a direct threat. New studies have been evaluating the potential effects of end-of-century elevated CO2 levels on sharks and their relatives' early development, physiology and behaviour. Here, we review those findings and use a meta-analysis approach to quantify the overall direction and magnitude of biological responses to OA in the species of sharks that have been investigated to date. While embryo survival and development time are mostly unaffected by elevated CO2, there are clear effects on body condition, growth, aerobic potential and behaviour (e.g. lateralization, hunting and prey detection). Furthermore, studies to date suggest that the effects of OA could be as substantial as those due to warming in some species. A major limitation is that all past studies have involved relatively sedentary, benthic sharks that are capable of buccal ventilation—no studies have investigated pelagic sharks that depend on ram ventilation. Future research should focus on species with different life strategies (e.g. pelagic, ram ventilators), climate zones (e.g. polar regions), habitats (e.g. open ocean), and distinct phases of ontogeny in order to fully predict how OA and climate change will impact higher-order predators and therefore marine ecosystem dynamics.
Rising sea levels increase the probability of future coastal flooding. Many decision-makers use risk analyses to inform the design of sea-level rise (SLR) adaptation strategies. These analyses are often silent on potentially relevant uncertainties. For example, some previous risk analyses use the expected, best, or large quantile (i.e., 90%) estimate of future SLR. Here, we use a case study to quantify and illustrate how neglecting SLR uncertainties can bias risk projections. Specifically, we focus on the future 100-yr (1% annual exceedance probability) coastal flood height (storm surge including SLR) in the year 2100 in the San Francisco Bay area. We find that accounting for uncertainty in future SLR increases the return level (the height associated with a probability of occurrence) by half a meter from roughly 2.2 to 2.7 m, compared to using the mean sea-level projection. Accounting for this uncertainty also changes the shape of the relationship between the return period (the inverse probability that an event of interest will occur) and the return level. For instance, incorporating uncertainties shortens the return period associated with the 2.2 m return level from a 100-yr to roughly a 7-yr return period (∼15% probability). Additionally, accounting for this uncertainty doubles the area at risk of flooding (the area to be flooded under a certain height; e.g., the 100-yr flood height) in San Francisco. These results indicate that the method of accounting for future SLR can have considerable impacts on the design of flood risk management strategies.
Despite the perilous status of many shark populations, rallying support for their conservation has been challenging, due in part to both long held negative perceptions and desire for shark fisheries. Recreational anglers are often advocates of conservation and can act as valuable partners with resource managers in developing fisheries management and conservation strategies. However, understanding their attitudes and perceptions, particularly towards resource status and management, is essential to developing successful management strategies and predicting outcomes. As a case study for assessing the complex challenges of sustainable shark fisheries, Florida recreational anglers were surveyed to understand how attitudes and perceptions influenced their willingness to donate for shark 1) conservation and protection or 2) fisheries sustainability. Overall, recreational angler willingness to donate was 25.5%, but attitudes and perceptions helped explain dramatic divides. For instance, willingness to donate was only 6% among the subset of anglers that perceived a growing large coastal shark population as a threat to recreational fishing opportunities. Highest support for shark conservation was shown by anglers who value seeing sharks in the wild (41.4%), and even more so among individuals who occasionally target sharks while fishing recreationally (65.8%). Pervasive among anglers unwilling to donate was a perception that shark populations were increasing, and thus not in need of further protection. These findings illustrate attitudes and perceptions that challenge shark conservation and fisheries management, as well as the critical importance of engaging anglers when developing strategies that rely on the recreational angling community for support.
The response of complex ecological communities to ocean acidification reflects interactions among species that propagate or dampen ecological change. Yet, most studies have been based on short-term experiments with limited numbers of interacting species. Both limitations tend to exaggerate measured effects and when combined with our predisposition for investigating change, we reduce insight into pathways of stability, acclimation and adaptation. Here, we review accepted and emerging insights into processes that drive ecological change (top-down and bottom-up) and the stabilizing processes by which ecological complexity may dampen change. With an emphasis on kelp forest examples, we show that boosted primary productivity from enriched CO2creates competitive imbalances that drive habitat change, but we also recognise intensifying herbivory on these habitats dampens this change. Foraging herbivores thrive on CO2 enriched plants and over successive generations their populations expand. When we consider such population level responses, we open new questions regarding density-effects (e.g. competition, susceptibility to predation and disease), as well as the bottom-up benefits to predators. Nevertheless, research on predators has lagged behind because their wide-ranging behaviour typically imposes logistical difficulties for observational and experimental research. We know that ocean warming imposes elevated metabolic costs on their foraging whilst acidification hampers navigation of their larvae towards suitable habitat and impairs their hunting and avoidance of predators as adults. Connecting such top-down with bottom-up responses is fundamental for progress, and is also contingent on understanding the mechanisms that dampen change. These stabilizers have the potential to keep pace with abiotic change and thereby influence the drivers of acclimation and adaption. Certainly, we acknowledge that investigating change is often simpler and associated bold messages appeal to citation impact. Yet, if we are to anticipate the ability of complex ecological communities to persist in changing environments, then understanding the shifting balance between the propagation of resource enrichment and its consumption across trophic levels is central to this challenge.
Distributions of Earth’s species are changing at accelerating rates, increasingly driven by human-mediated climate change. Such changes are already altering the composition of ecological communities, but beyond conservation of natural systems, how and why does this matter? We review evidence that climate-driven species redistribution at regional to global scales affects ecosystem functioning, human well-being, and the dynamics of climate change itself. Production of natural resources required for food security, patterns of disease transmission, and processes of carbon sequestration are all altered by changes in species distribution. Consideration of these effects of biodiversity redistribution is critical yet lacking in most mitigation and adaptation strategies, including the United Nation’s Sustainable Development Goals.
In global climate change scenarios, seawater warming acts in concert with multiple stress sources, which may enhance the susceptibility of marine biota to thermal stress. Here, the responsiveness to seasonal gradual warming was investigated in temperate mussels from a chronically stressed population in comparison with a healthy one. Stressed and healthy mussels were subjected to gradual temperature elevation for 8 days (1°C per day; fall: 16–24°C, winter: 12–20°C, summer: 20–28°C) and kept at elevated temperature for 3 weeks. Healthy mussels experienced thermal stress and entered the time-limited survival period in the fall, became acclimated in winter and exhibited sublethal damage in summer. In stressed mussels, thermal stress and subsequent health deterioration were elicited in the fall but no transition into the critical period of time-limited survival was observed. Stressed mussels did not become acclimated to 20°C in winter, when they experienced low-to-moderate thermal stress, and did not experience sublethal damage at 28°C in summer, showing instead signs of metabolic rate depression. Overall, although the thermal threshold was lowered in chronically stressed mussels, they exhibited enhanced tolerance to seasonal gradual warming, especially in summer. These results challenge current assumptions on the susceptibility of marine biota to the interactive effects of seawater warming and pollution.