Rehabilitated and restored mangrove ecosystems have important ecological, economic, and social values for coastal communities. Although a sine qua non of successful mangrove rehabilitation or restoration projects is accurate attention to local hydrology and basic biology of mangrove trees and their associated fauna, their long-term success depends on far more axes, each with their own challenges. Rehabilitation projects: are planned, designed, executed, and managed by people with diverse backgrounds and different scientific and socio-political agendas; need to be responsive to these multiple stakeholders and agents who hold different values; are often influenced by laws and treaties spanning local to international scales; and must be able to adapt and evolve both geomorphologically and socioeconomically over decades-to-centuries in the context of a rapidly changing climate. We view these challenges as opportunities for innovative approaches to rehabilitation and restoration that engage new and larger constituencies. Restored mangrove ecosystems can be deliberately designed and engineered to provide valuable ecosystem services, be adaptable to climatic changes, and to develop platforms for educating nonspecialists about both the successes and failures of restored mangrove ecosystems. When mangrove rehabilitation or restoration projects are developed as experiments, they can be used as case-studies and more general models to inform policy- and decision-makers and guide future restoration efforts. Achieving this vision will require new investment and dedication to research and adaptive management practices. These ideas are illustrated with examples from mangrove restoration and rehabilitation projects in the Indo-West Pacific and Caribbean regions, the two hotspots of mangrove biodiversity and its ongoing loss and degradation.
Effective biological treatment of marine wastewater is not well-known. Accumulation of nitrogen and phosphorus from land-based effluent is a crucial cause of red-tide in marine systems. The purpose of the study is to reduce nitrogen and phosphorus in marine wastewater with a pilot plant-scale sequencing batch reactor (SBR) system by using marine sediment as eco-friendly and effective biological materials, and elucidate which bacterial strains in sludge from marine sediment influence the performance of SBR. By applying eco-friendly high efficiency marine sludge (eco-HEMS), the treatment performance was 15 m3 d-1 of treatment amount in 4.5 m3 of the reactor with the average removal efficiency of 89.3% for total nitrogen and 94.9% for total phosphorus at the optimal operation condition in summer. Moreover, the average removal efficiency was 84.0% for total nitrogen and 88.3% for total phosphorus in winter although biological treatment efficiency in winter is generally lower due to bacterial lower activity. These results were revealed by the DNA barcoding analysis of 16s rRNA amplicon sequencing of samples from the sludge in winter. The comparative analysis of the bacterial community composition in sludge at the high efficiency of the system showed the predominant genera Psychromonas (significantly increased to 45.6% relative abundance), Vibrio (13.3%), Gaetbulibacter (5.7%), and Psychroserpens (4.3%) in the 4 week adaptation after adding marine sediment, suggesting that those predominant bacteria influenced the treatment performance in winter.
This study provides an overview of 11 lagoons in North Africa, from the Atlantic to the Eastern Mediterranean. Lagoons are complex, transitional, coastal zones providing valuable ecosystem services that contribute to the welfare of the human population. The main economic sectors in the lagoons included fishing, shellfish harvesting, and salt and sand extraction, as well as maritime transport. Economic sectors in the areas around the lagoons and in the watershed included agriculture, tourism, recreation, industrial, and urban development. Changes were also identified in land use from reclamation, changes in hydrology, changes in sedimentology from damming, inlet modifications, and coastal engineering. The human activities in and around the lagoons exert multiple pressures on these ecosystems and result in changes in the environment, affecting salinity, dissolved oxygen, and erosion; changes in the ecology, such as loss of biodiversity; and changes in the delivery of valuable ecosystem services. Loss of ecosystem services such as coastal protection and seafood affect human populations that live around the lagoons and depend on them for their livelihood. Adaptive management frameworks for social–ecological systems provide options that support decision makers with science-based knowledge to deliver sustainable development for ecosystems. The framework used to support the decision makers for environmental management of these 11 lagoons is Drivers–Activities–Pressures–State Change–Impact (on Welfare)–Responses (as Measures).
Transient fish spawning aggregations (FSAs) are critical life‐cycle events for many commercially important species, in which fish congregate in huge numbers to spawn at predictable times and places. This behavior makes them exceptionally vulnerable to fishing. The “illusion of plenty” and poor access to monitoring tools and techniques has resulted in some FSAs being overfished or unwittingly eliminated. We present a co‐conservation network, formally linking site‐focused partners who cooperatively monitor and actively manage multispecies FSAs. FSA sites and networks offer great potential as conservation bright spots to replenish fished populations, rehabilitate marine ecosystems, and ensure the flow of ecosystem services to the millions of people that rely upon them for their wellbeing. We call for urgent global recognition of FSAs as effective spatial nexus for addressing multiple interconnected global policy targets for a sustainable ocean.
Tropical coastal environment represents one of the most dynamic and vital interfaces on Earth, at the boundary between land and sea. It encompasses some of the most diverse and productive habitats. These habitats include natural ecosystems, managed ecosystems besides major urban centres. The existence of these ecosystems is dependent on the land-sea interconnection and dynamic flow of energy and matter. At the same time, the coastal region has long been under stress from over-exploitation and mismanagement. The increasing pace of human population and developmental activities in the tropical coastal region has altered the functionality of coastal ecosystems and endangered several flora and fauna that threaten the livelihood of people who depend on them. In addition, the looming spectre of sea level rise associated with the effect of global warming presents a new and potentially far more dangerous threat to this region. This necessitates suitable coastal zone management plan to conserve and derive sustainable benefit from the coastal ecosystems. With this background an overview of tropical coastal countries, its demographic features, natural resources, coastal ecosystems, and its services to the human society are discussed in this chapter. Brief account on effect of human activities and climate change on coastal region sourced from different literatures provides useful information to the researchers, students, and policymakers.
In a context of growing concern about climate change and its potential consequences for coastal systems, adaptation is becoming more important than ever before. This paper presents a national planning framework for adaptation to climate change, which is pioneer in the field as it is multi-sectoral and focuses specifically on coastal areas, pursuing the safety of their communities in an uncertain future. The strategy is statutory as it emanates from the new Spanish Coastal Law, which in addition to many other implications includes the compulsory development of a Spanish Strategy for Coastal Adaptation to Climate Change (SSCACC) and its submission to Strategic Environmental Assessment. This paper covers the fundamental aspects of both the SSCACC and the accompanying Strategic Environmental Study, providing recommendations on the assessment of coastal risks triggered by climate change and extreme events, adaptation and risk reduction planning and implementation, and monitoring. Additionally, this work gives insight into the wide-ranging consultation process carried out prior to the SSCACC's approval and the stakeholders involved, and how the SSCACC handles climate change uncertainty and struggles for overcoming barriers.
Climate change impacts on fisheries will undoubtedly have socio-economic impacts on coastal communities and the seafood market. However, it is a challenge to integrate climate change information in a form that can be used efficiently by adaptation planners, policy makers, and fishery managers. In this study, we frame a climate change impact assessment using a geographical perspective based on the management units of the dominant fishery, in this case, American lobster in Nova Scotia, Canada. The information considered here includes economic dependence on the fishery, population size, diversity of the fishery revenue, status of harbor infrastructure, total replacement cost of each harbor, increased relative sea level and flooding, and the vulnerability of offshore lobster to ocean warming and changes in zooplankton composition and anticipatory changes in fishery productivity across management borders. Using two ocean models to provide multi-decadal scale projections of bottom temperature, changes in offshore lobster distribution are projected to have a neutral, or positive impact on the region as a whole. However, when lobster vulnerability is combined with climate change related vulnerabilities of coastal fishing communities, it is evident that adaptation planning is needed for long-term sustainability. This impact assessment provides both a framework and information for further in-depth analyses by climate change adaptation planners and fishery managers.
Nest predation is considered to be one of the most significant biotic threats to marine turtle populations globally. The introduction of feral predators to nesting beaches has dramatically increased nest predation, reaching near total egg loss in some regions. We monitored a 48 km stretch of beach along western Cape York Peninsula, Australia, from June – November 2018. We recorded a total of 360 nests comprising 117 flatback and 243 olive ridley nests. We installed plastic meshing (90 cm × 100 cm) on 110 olive ridley nests (45.2% of total olive ridley clutches laid) within the study area. We classified all nest predation attempts into three categories: complete, partial, or failed predation events. In total, 109 (30.2%) of all marine turtle nests were depredated by a variety of predators, including feral pigs, dingoes, goannas, and humans. The addition of plastic meshing reduced the likelihood of dingoes gaining access to eggs, but not goannas or feral pigs. Further, we found no difference in the proportion of hatchling emergence between meshed and un-meshed nests. Additionally, while hatchling emergence was reduced in nests that had been partially depredated, these nests still produced live hatchlings and contributed to recruitment. The success of particular predator control methods is often predator, and/or regionally, specific. Our findings highlight a thorough understanding of predator guilds and their relative impacts is required to deploy targeted and predator-specific strategies to maximize conservation results. We present a strong case for data-driven adaptive management that has implications for designing optimal predator management plans.
Active coral restoration typically involves two interventions: crossing gametes to facilitate sexual larval propagation; and fragmenting, growing, and outplanting adult colonies to enhance asexual propagation. From an evolutionary perspective, the goal of these efforts is to establish self‐sustaining, sexually reproducing coral populations that have sufficient genetic and phenotypic variation to adapt to changing environments. Here, we provide concrete guidelines to help restoration practitioners meet this goal for most Caribbean species of interest. To enable the persistence of coral populations exposed to severe selection pressure from many stressors, a mixed provenance strategy is suggested: genetically unique colonies (genets) should be sourced both locally as well as from more distant, environmentally distinct sites. Sourcing 3‐4 genets per reef along environmental gradients should be sufficient to capture a majority of intraspecies genetic diversity. It is best for practitioners to propagate genets with one or more phenotypic traits that are predicted to be valuable in the future, such as low partial mortality, high would healing rate, high skeletal growth rate, bleaching resilience, infectious disease resilience, and high sexual reproductive output. Some effort should also be reserved for underperforming genets because colonies that grow poorly in nurseries sometimes thrive once returned to the reef and may harbor genetic variants with as yet unrecognized value. Outplants should be clustered in groups of 4‐6 genets to enable successful fertilization upon maturation. Current evidence indicates that translocating genets among distant reefs is unlikely to be problematic from a population genetic perspective but will likely provide substantial adaptive benefits. Similarly, inbreeding depression is not a concern given that current practices only raise first‐generation offspring. Thus, proceeding with the proposed management strategies even in the absence of a detailed population genetic analysis of the focal species at sites targeted for restoration is the best course of action. These basic guidelines should help maximize the adaptive potential of reef‐building corals facing a rapidly changing environment.