Sustainable landscape planning and management of coastal habitats has become an integral part of the global agenda due to anthroprogenic pressures and climate change-induced events. As an example of human-engineered infrastructure that enhances the sustainability and resilience of coastal social-ecological systems (SES), we have presented the dumbeong system, a farmer-engineered and managed irrigation system based on Korean traditional ecological knowledge. We analyzed the spatial relationship of dumbeongs with coastal landscape attributes and droughts in Goseong County in South Korea. We used generalized linear models (GLMs) to examine the effects of land cover and recent (2001–2010) standardized precipitation index (SPI) on the abundance of dumbeongs. Then, we projected near future (2020–2050) changes in the SPI-based drought risk for the dumbeong system using representative concentration pathway (RCP) climate scenarios. We found that forest and marine water areas have positive relations with dumbeong abundance, whereas SPI has a negative relation, indicating that the dumbeongs are more abundant in areas close to sea water and forests, and with higher incidences of drought. Derived climate change scenarios show that the study region will experience higher incidence of drought. Our findings provide empirical evidence for the dumbeongsystem as an effective community designed and driven adaptive response to local hydrological processes and climatic conditions, and as climate-resilient infrastructure that strengthens sustainability and resilience of coastal SES. Based on our findings, we provide recommendations for sustainable landscape management and optimal use of the dumbeong system in coastal regions.
Marine debris is defined as any persistent solid material disposed into the marine and/or coastal environment. The impact of these pieces of debris, especially plastic, have been reported around the world as causing environmental degradation, disease dissemination, transport of chemical toxins and public health issues. The extent of the effects of marine debris and beach cleanliness can be assessed using indexes such as General Index (GI), Clean-Coast Index (CCI) and Pellet Pollution Index (PPI). Thus, this study analyzed all debris collected from 25 beaches located in 11 counties in the State of Santa Catarina, Brazil. The quali-quantitative analysis was used for individual beaches according to the above indexes. Although plastic was the overall most common debris category, granulated polystyrene was the most common debris in nine of the beaches in this study. From the three indexes employed in this study, GI appears to be the most appropriate as it considers all debris sizes, while CCI underestimates the pollution level of the beaches as it only takes into consideration plastic debris over 2 cm. Similarly, PPI ranked all sites as having low pollution levels, despite the high threats that pellets may pose to marine biota.
Items of marine plastic litter are conventionally classified as primary or secondary, depending on whether they are distinct objects or angular fragments, respectively. “Pyroplastic” is an additional type of plastic litter that is described here, based on observations made on beached samples from south west England. Pyroplastics are derived from the informal or more organised burning of manufactured plastics and may be angular “plastiglomerates”, comprising pieces of plastic debris within a matrix, or rounded plastic “pebbles”, where agglomerated material has been weathered and smoothed into more brittle and neutrally-coloured geogenic-looking clasts. Beached pyroplastics are usually positively buoyant because of a polyethylene or polypropylene matrix, and exhibit a bimodal mass distribution attributed to the breakage of larger clasts (>20 mm) into smaller fragments (<5 mm). XRF analysis reveals variable quantities of Pb in the matrix (up to 7500 μg g−1), often in the presence of Cr, implying that material in many samples pre-dates restrictions on the use of lead chromate. Low concentrations of Br and Sb relative to pieces of manufactured plastics in the marine environment suggest that pyroplastics are not directly or indirectly derived from electronic plastic. Calcareous worm tubes on the surfaces of pyroplastics dense enough to be temporarily submerged in the circalittoral zone are enriched in Pb, suggesting that constituents within the matrix are partly bioavailable. Evading ready detection due to their striking visual similarity to geogenic material, pyroplastics may contribute to an underestimation of the stock of beached plastics in many cases.
Plastic debris becomes currently a ubiquitous environmental pollutant and is susceptible to contamination by many other pollutants, including aqueous metals and organic matter. This review summarizes the effects of environmental factors on the properties and sorption behavior of microplastics, presents a further discussion on the fate of microplastics adsorption on contaminants, and critically discusses the mechanism of sorption behaviors between micro/nanoplastics and normal contaminants. Previous references indicated that the hydrophobicity and particle sizes of microplastics were the dominant influence factors for virgin plastic debris adsorption, whereas for aged microplastics, hydrogen bonding, hydrophilicity and increasing specific surface ratio affected the adsorption behavior. The effects of pH and salinity always influence the sorption conditions by changing the charge state of microplastics and contaminants and causing competing adsorption. In addition, the existence of microplastics affects biotoxicity, increases the dissolved organic matter in the environment, and influences carbon cycling. The knowledge is fundamental to the assessment of potential risks posed by microplastics to organisms from human beings to the entire environment.
Tidal habitats sustain fragile ecosystems, undergoing pressures from coastal artificialization and rising sea levels. Saltpans are a substitution habitat for birds that breed, winter or stop-over along coastlands where most pristine tidal habitats have been removed. Balancing the economical, patrimonial and biodiversity values of former saltpans is thus needed to mitigate the threats posed by global changes on waterbirds. In this study, we scrutinized the influence of management practices on waterbirds on two isolated saltpans located on the French Mediterranean shore, several tens of kilometres apart from other suitable habitats. We analysed three years of bird counts for nine protected species that breed, forage and roost on these saltpans. We used a multispecies hierarchical model to relate variations in bird counts to water levels, oxygenation and salinity, the three parameters targeted by the saltpans management plan to promote bird settlement. We showed that the hypersaline conditions that dominate in these saltpans are suboptimum to most species, suggesting that waterbird concentrations are dictated by the lack of alternatives in the surrounding landscape rather than by habitat suitability. Intraspecific variations in species' responses to these variables should orient towards the creation of a habitat mosaic within the saltpans. Eventually, between-site differences in bird responses to water conditions pointed the effects of disturbance, predation and other landscape-level features. Our results reveal that high waterbird numbers on isolated saltpans may be a misleading measure of their ecological suitability, and that management on these sites needs to incorporate conflicts and complementarity in species' habitat use.
Ecological resilience, broadly defined as the magnitude of the disturbance a system needs to shift to an alternative stable state, is becoming a critical trait in the Anthropocene era. However, we are far from having baseline resilience data to guide decision makers toward more resilient ecological systems. In the last decade, the resilience assessment framework has taken a sum of products approach to obtain a resilience indicator based on the relevance and the intensity of multiple factors. While factor intensity relies on quantitative data, estimates of factor relevance rely on ordinal data with a lesser understanding of their relative importance to resilience, which may have consequences in the value of the resilience indicator. Here, we computed three resilience indicators to test for the quantitative impact that changes in factor relevance might cause to the resilience indicator. We defined the Inclusive Resilience Indicator of a Site (IRIS) as a relevance-free indicator based exclusively on factor intensity. We also computed the Relative Resilience Potential (RRP) and an RRP with random relevance values (RRPrrv) as indicators based on both intensity and relevance. To calculate these three indicators in rocky reefs of the Alboran Sea, we quantified 17 biological, environmental, and human-related factors known to influence resilience. We used correlation analyses, Linear Mixed Models, and Generalized Additive Models to compare the three resilience indicators and to examine their spatial patterns. We found highly significant positive correlations between the RRP, RRPrrv, and IRISindicators (r > 0.9, p < 0.001 for all comparisons). All three indicators had equivalent resilience values (p = 0.440), provided non-significant differences in their predictions (p = 0.097), and exposed the same resilience gradients in the Alboran Sea (p < 0.001 for all indicators). IRISaccounted for 94% and 99% of the variance associated with RRP and RRPrrv, respectively, suggesting that the intensity-based IRIS can estimate resilience without the uncertainties associated with factor relevance. The new IRIS indicator proposed in our study may facilitate the acquisition of baseline data needed to further advance in the ecological and management implications of marine resilience.
The spatial structure and dynamics of populations, their environment, interacting species, and anthropogenic stressors influences community stability and ecological resilience. Despite the importance of spatial processes in ecological outcomes and increasing desire to implement ecosystem-based management, fine-scale spatial dynamics have been rarely incorporated in marine fisheries management. However, advances in population modeling and data availability provide the necessary ingredients to address this disconnect between the fields of ecology and fisheries. We used random forests and spatial indices to quantify spatial heterogeneity and dynamics of US west coast demersal marine faunal density (biomass of a community or assemblage per unit area) and the total removals (catches plus discards) from the system by the groundfish bottom trawl fishery from 2002 to 2017. We expected spatial heterogeneity of removals and density to increase following implementation of depth and habitat closures – due to proximally increasing density gradients and fishing-the-line – and following catch shares because of fleet consolidation and behavioral consequences of eliminating the race to fish. However, we found mixed responses, where at the broadest community levels spatial variation in removals and density declined with habitat closures, while spatial autocorrelation of removals increased with habitat closures and declined with catch shares. Our results reveal a complex interdependence between spatial distributions of faunal density and fishery removals that has been absent in previous studies focusing on catch only, and shows how these patterns are shaped by marine policy. Values of spatial variation of density and removals were positively correlated within year (i.e., each responded with the same sign and timescale), while there was also evidence that interannual changes in the spatial variation of removals among years led those of density by one year (i.e., increases in patchiness of removals were followed by increased patchiness of density). These results hint at the presence of a stronger than expected top-down effect of fishing, given that this system is considered to be dominated by strong bottom-up effects of environmental variation on primary and secondary productivity.
This paper examines governance effectiveness of the Wildlife Refuge of Punta de Manabique (RVSPM), the first recognized marine protected area in Guatemala. The analysis follows the Marine Protected Area Governance (MPAG) empirical framework through the use of incentives (economic, interpretative, knowledge, legal and participative) that evaluate the effectiveness of governance. Our results highlight that strategic alliances between some local communities and NGOs have successfully provided economic and participatory incentives for better management. However, efforts to develop an integrated or collaborative management system that promotes sustainable resource use across all stakeholder groups have failed. As a result, environmental degradation is increasing at an alarming rate, set against a backdrop of declining management effectiveness. Under this scenario, future prospects for governance should revise participatory incentives and strengthen legal incentives, which should be backed by strong political will. In addition, efforts should continue to foster opportunities for regional collaborations as an essential element for improved governance of the RVSPM and as a foundation to effectively manage natural and cultural resources in the wider Mesoamerican Reef region.
Fishery and wildlife managers face important challenges in reconciling recovery of historically over-harvested or extirpated populations of marine mammals with effective fisheries management. For example, the reestablishment of sea otters in British Columbia (B.C.) has had repercussions that led to one of the more interesting resource management problems involving commercial fisheries in Canada. As a case study, this paper reviews the history of sea otter exploitation and reintroduction in B.C., and discusses the nature and context of the problem today. Fisheries and marine mammals in Canada continue to be managed under overlapping legislative mandates and often with quite different goals. The case study highlights persistent social and institutional constraints on reconciling marine mammal-fishery conflicts. To reduce tensions and uncertainty, Fisheries and Oceans Canada should prioritize intensive marine mammal sampling programs for non-endangered species to disentangle fishing and predation effects, and fully implement Species At Risk Act and Fisheries Act measures to reduce uncertainty among increasingly diverse stakeholders.
Marine protected areas (MPAs) make a significant contribution to the protection of marine communities through the provision of sustainable livelihoods, financial benefits related to fisheries and tourism, as well as the restoration of ocean productivity and the prevention of further degradation. Due to the inefficient management of MPAs, however, the marine ecosystem has been greatly affected by the substantial reduction in fish biomass, resulting in loss of biodiversity and extinction of species in MPAs. Malaysia, one of the top 12 megadiverse countries in the world, places great importance on the conservation and sustainable use of its rich natural heritage. In Malaysia, the concept of MPAs was introduced in the 1980s to raise public awareness on declining fisheries resources and ecosystem degradation. These MPAs have been established to address the threats to marine, coastal, and island ecosystems. The development of MPAs around the world, and particularly in Malaysia, is an essential geo-ecological element, not only for biodiversity, but also for society and the economy. There are four categories of MPAs in Malaysia: marine parks, no-take zones, wildlife sanctuaries, and turtle sanctuaries. For a better understanding of MPAs in Malaysia, it is relevant to provide a global overview before focusing on the Malaysian context.
Major ecological realignments are already occurring in response to climate change. To be successful, conservation strategies now need to account for geographical patterns in traits sensitive to climate change, as well as climate threats to species-level diversity. As part of an effort to provide such information, we conducted a climate vulnerability assessment that included all anadromous Pacific salmon and steelhead (Oncorhynchus spp.) population units listed under the U.S. Endangered Species Act. Using an expert-based scoring system, we ranked 20 attributes for the 28 listed units and 5 additional units. Attributes captured biological sensitivity, or the strength of linkages between each listing unit and the present climate; climate exposure, or the magnitude of projected change in local environmental conditions; and adaptive capacity, or the ability to modify phenotypes to cope with new climatic conditions. Each listing unit was then assigned one of four vulnerability categories. Units ranked most vulnerable overall were Chinook (O. tshawytscha) in the California Central Valley, coho (O. kisutch) in California and southern Oregon, sockeye (O. nerka) in the Snake River Basin, and spring-run Chinook in the interior Columbia and Willamette River Basins. We identified units with similar vulnerability profiles using a hierarchical cluster analysis. Life history characteristics, especially freshwater and estuary residence times, interplayed with gradations in exposure from south to north and from coastal to interior regions to generate landscape-level patterns within each species. Nearly all listing units faced high exposures to projected increases in stream temperature, sea surface temperature, and ocean acidification, but other aspects of exposure peaked in particular regions. Anthropogenic factors, especially migration barriers, habitat degradation, and hatchery influence, have reduced the adaptive capacity of most steelhead and salmon populations. Enhancing adaptive capacity is essential to mitigate for the increasing threat of climate change. Collectively, these results provide a framework to support recovery planning that considers climate impacts on the majority of West Coast anadromous salmonids.
Marine protected areas (MPAs) in Malaysia are greatly constrained by a host of problems and challenges such as ineffective management, poor institutional capacity, limited enforcement, absence of awareness, and poor socioeconomic status (SES) which influence the conservation of marine resources. Environmental degradation is another issue, including anthropogenic activities, overexploitation of marine resources, water quality deterioration, massive waste generation, and climate changes. These are the main impediments to sustainable economic growth, social development, and conservation of natural resources. This chapter details the major hurdles to sustainable community development within MPAs in Malaysia. It would help policymakers resolve the problems associated with marine park management and take appropriate steps to preserve, conserve, and protect marine resources for sustainable community development.
Marine protected areas (MPAs) are management tools to conserve, preserve, and protect marine biodiversity, cultural heritage, and sustainable production of fisheries. Simultaneously, MPAs have the potential to ensure competent management of marine ecosystems. To stimulate the conservation and sustainable use of marine resources, global policymakers have introduced the 14th sustainable development goal (SDG-14). The Convention on Biological Diversity (CBD) focuses on increasing the current size of global MPAs. They have set targets to increase the size of global MPAs to 10% by 2020 and at least 30% by 2030 to accomplish SDG-14. This chapter discusses an overview of SDG-14, CBD initiatives, the Coral Triangle Initiative by six Coral Triangle countries, and challenges to achieve SDG-14 by 2030.
There has been a dramatic increase in recentyears in the number of papers, reports, etc.,which have been published concerning MarineProtected Areas (MPAs). This overview of theobjectives, selection, design and management ofMPAs aims to provide a basis for discussionregarding possible ways forward by identifyingemerging issues, convergences and divergences. Whilst the attributes of the marine environmentmay limit the effectiveness of site-specificinitiatives such as MPAs, it is argued that itwould be defeatist in the extreme to abandonMPAs in the face of these limitations. Ten keyobjectives for MPAs are discussed, includingthat of harvest refugia, and it is argued thatwhilst these objectives may be justifiable froma preservationist perspective, they may beobjected to from a resource exploitationperspective. MPAs generate both internal(between uses) and basic (between use andconservation) conflicts, and it is argued thatthese conflicts may be exacerbated whenscientific arguments for MPAs are motivated bypreservationist concerns. It is reported thata minority of MPAs are achieving theirmanagement objectives, and that for themajority insufficient information was availablefor such effectiveness evaluations. Structureand process-oriented perspectives on marineconservation are discussed. It is argued thatthere are two divergent stances concerningoptimal MPA management approaches: top-down,characterized as being government-led andscience-based, with a greater emphasis onset-aside; and bottom-up, characterized asbeing community-based and science-guided, witha greater emphasis on multiple-use. Given thedivergent values of different stakeholders, thehigh degree of scientific uncertainty, and thehigh marine resource management decisionstakes, it is concluded that a key challenge isto adopt a "middle-ground" approach whichcombines top-down and bottom-up approaches, andwhich is consistent with the post-normalscientific approach.
Effects of combined rising sea temperature and increasing sea level on coral reefs, both factors associated with global warming, have rarely been addressed. In this ~40 y study of shallow reefs in the eastern Indian Ocean, we show that a rising relative sea level, currently estimated at ~11 mm y−1, has not only promoted coral cover but also has potential to limit damaging effects of thermally-induced bleaching. In 2010 the region experienced the most severe bleaching on record with corals subject to sea temperatures of >31 °C for 7 weeks. While the reef flats studied have a common aspect and are dominated by a similar suite of coral species, there was considerable spatial variation in their bleaching response which corresponded with reef-flat depth. Greatest loss of coral cover and community structure disruption occurred on the shallowest reef flats. Damage was less severe on the deepest reef flat where corals were subject to less aerial exposure, rapid flushing and longer submergence in turbid waters. Recovery of the most damaged sites took only ~8 y. While future trajectories of these resilient reefs will depend on sea-level anomalies, and frequency of extreme bleaching the positive role of rising sea level should not be under-estimated.
Ocean plastic is a contemporary focal point of concern for the marine environment. However, we argue there are bigger issues to address, including climate change and overfishing. Plastic has become a focus in the media and public domains partly through the draw of simple lifestyle changes, such as reusable water bottles, and partly through the potential to provide ‘quick fix’ technological solutions to plastic pollution, such as large scale marine clean-up operations and new ‘biodegradable’ plastic substitutes. As such, ocean plastic can provide a convenient truth that distracts us from the need for more radical changes to our behavioural, political and economic systems, addressing which will help address larger marine environmental issues, as well as the cause of plastic pollution, i.e. over-consumption.
We agree with Avery-Gomm et al. that we should not separate out environmental issues. We also agree with them over the relative threat of plastic to our oceans. However, recent evidence on the ‘spillover effect’ of pro-environmental behaviours and on public attitudes to threats to areas such as the Great Barrier Reef suggest common consumerist and political approaches to tackle plastic pollution can cause a distraction from issues caused by climate change and biodiversity loss. We reiterate that we need political changes to address overconsumption in order to make real progress on all environmental issues.
Mesopelagic sound scattering layers (SSL) are ubiquitous in all oceans. Pelagic organisms within the SSL play important roles as prey for higher trophic levels and in climate regulation through the biological carbon pump. Yet, the biomass and species composition of SSL in the Arctic Ocean remain poorly documented, particularly in winter. A multifrequency echosounder detected a SSL north of Svalbard, from 79.8 to 81.4°N, in January 2016, August 2016, and January 2017. Midwater trawl sampling confirmed that the SSL comprised zooplankton and pelagic fish of boreal and Arctic origins. Arctic cod dominated the fish assemblage in August and juvenile beaked redfish in January. The macrozooplankton community mainly comprised the medusa Cyanea capillata, the amphipod Themisto libellula, and the euphausiids Meganyctiphanes norvegica in August and Thysanoessa inermis in January. The SSL was located in the Atlantic Water mass, between 200–700 m in August and between 50–500 m in January. In January, the SSL was shallower and weaker above the deeper basin, where less Atlantic Water penetrated. The energy content available in the form of lipids within the SSL was significantly higher in summer than winter. The biomass within the SSL was >12-fold higher in summer, and the diversity of fish was slightly higher than in winter (12 vs. 9 species). We suggest that these differences are mainly related to life history and ontogenetic changes resulting in a descent toward the seafloor, outside the mesopelagic layer, in winter. In addition, some fish species of boreal origin, such as the spotted barracudina, did not seem to survive the polar night when advected from the Atlantic into the Arctic. Others, mainly juvenile beaked redfish, were abundant in both summer and winter, implying that the species can survive the polar night and possibly extend its range into the high Arctic. Fatty-acid trophic markers revealed that Arctic cod mainly fed on calanoid copepods while juvenile beaked redfish targeted krill (Thysanoessa spp.). The relatively high biomass of Arctic cod in August and of redfish in January thus suggests a shift within the SSL, from a Calanus-based food web in summer to a krill-based food web during winter.
Ocean warming can drive poleward shifts of commercially important species with potentially significant economic impacts. Nowhere are those impacts greater than in the Gulf of Maine where North America's most valuable marine species, the American lobster (Homarus americanus Milne Edwards), has thrived for decades. However, concerns are growing as monitored shallow water young‐of‐year lobsters decline and landings shift to the northeast that the regional maritime economies will suffer. We examine how the interplay of ocean warming, tidal mixing, and larval behavior results in a brighter side of climate change. Since the 1980s lobster stocks have increased fivefold. We suggest this increase resulted from a complex interplay between lobster larvae settlement behavior, climate change, and local oceanographic conditions. Specifically, postlarval sounding behavior is confined to a thermal envelope above 12°C and below 20°C. Summer thermally‐stratified surface water in southwestern regions have historically been well within the settlement thermal envelope. Although surface layers are warming fastest in this region, the steep depth‐wise temperature gradient caused thermally‐suitable areas for larval settlement to expand only modestly. This contrasts with the northeast where strong tidal mixing prevents thermal stratification and recent ocean warming has made an expansive area of seabed more favorable for larval settlement. Recent declines in lobster settlement densities observed at shallow monitoring sites correlate with the expanded area of thermally‐suitable habitat associated with warmer summers. This leads us to hypothesize that the expanded area of suitable habitat may help explain strong lobster population increases in this region over the last decade and offset potential future declines. It also suggests that the fate of fisheries in a changing climate requires understanding local interaction between life‐stage‐specific biological thresholds and finer scale oceanographic processes.
The Phoenix Islands Protected Area (PIPA), one of the world’s largest marine protected areas, represents 11% of the exclusive economic zone of the Republic of Kiribati, which earns much of its GDP by selling tuna fishing licenses to foreign nations. We have determined that PIPA is a spawning area for skipjack (Katsuwonus pelamis), bigeye (Thunnus obesus), and yellowfin (Thunnus albacares) tunas. Our approach included sampling larvae on cruises in 2015–2017 and using a biological-physical model to estimate spawning locations for collected larvae. Temperature and chlorophyll conditions varied markedly due to observed ENSO states: El Niño (2015) and neutral (2016–2017). However, larval tuna distributions were similar amongst years. Generally, skipjack larvae were patchy and more abundant near PIPA’s northeast corner, while Thunnus larvae exhibited lower and more even abundances. Genetic barcoding confirmed the presence of bigeye (Thunnus obesus) and yellowfin (Thunnus albacares) tuna larvae. Model simulations indicated that most of the larvae collected inside PIPA in 2015 were spawned inside, while stronger currents in 2016 moved more larvae across PIPA’s boundaries. Larval distributions and relative spawning output simulations indicated that both focal taxa spawned inside PIPA in all 3 study years, demonstrating that PIPA is protecting viable tuna spawning habitat.