Untangling social-ecological interactions: A methods portfolio approach to tackling contemporary sustainability challenges in fisheries.

Meeting the objectives of sustainable fisheries management requires attention to the complex interactions between humans, institutions and ecosystems that give rise to fishery outcomes. Traditional approaches to studying fisheries often do not fully capture, nor focus on these complex interactions between people and ecosystems. Despite advances in the scope and scale of interactions encompassed by more holistic methods, for example ecosystem-based fisheries management approaches, no single method can adequately capture the complexity of human-nature interactions. Approaches that combine quantitative and qualitative analytical approaches are necessary to generate a deeper understanding of these interactions and illuminate pathways to address fisheries sustainability challenges. However, combining methods is inherently challenging and requires understanding multiple methods from different, often disciplinarily distinct origins, demanding reflexivity of the researchers involved. Social-ecological systems' research has a history of utilising combinations of methods across the social and ecological realms to account for spatial and temporal dynamics, uncertainty and feedbacks that are key components of fisheries. We describe several categories of analytical methods (statistical modelling, network analysis, dynamic modelling, qualitative analysis and controlled behavioural experiments) and highlight their applications in fisheries research, strengths and limitations, data needs and overall objectives. We then discuss important considerations of a methods portfolio development process, including reflexivity, epistemological and ontological concerns and illustrate these considerations via three case studies. We show that, by expanding their methods portfolios, researchers will be better equipped to study the complex interactions shaping fisheries and contribute to solutions for sustainable fisheries management.

Global Aquaculture Productivity, Environmental Sustainability, and Climate Change Adaptability.

To meet the demand for food from a growing global population, aquaculture production is under great pressure to increase as capture fisheries have stagnated. However, aquaculture has raised a range of environmental concerns, and further increases in aquaculture production will face widespread environmental challenges. The effects of climate change will pose a further threat to global aquaculture production. Aquaculture is often at risk from a combination of climatic variables, including cyclone, drought, flood, global warming, ocean acidification, rainfall variation, salinity, and sea level rise. For aquaculture growth to be sustainable its environmental impacts must reduce significantly. Adaptation to climate change is also needed to produce more fish without environmental impacts. Some adaptation strategies including integrated aquaculture, recirculating aquaculture systems (RAS), and the expansion of seafood farming could increase aquaculture productivity, environmental sustainability, and climate change adaptability.

Integrated mangrove-shrimp cultivation: Potential for blue carbon sequestration.

Globally, shrimp farming has had devastating effects on mangrove forests. However, mangroves are the most carbon-rich forests, with blue carbon (i.e., carbon in coastal and marine ecosystems) emissions seriously augmented due to devastating effects on mangrove forests. Nevertheless, integrated mangrove-shrimp cultivation has emerged as a part of the potential solution to blue carbon emissions. Integrated mangrove-shrimp farming is also known as organic aquaculture if deforested mangrove area does not exceed 50% of the total farm area. Mangrove destruction is not permitted in organic aquaculture and the former mangrove area in parts of the shrimp farm shall be reforested to at least 50% during a period of maximum 5 years according to Naturland organic aquaculture standards. This article reviews integrated mangrove-shrimp cultivation that can help to sequester blue carbon through mangrove restoration, which can be an option for climate change mitigation. However, the adoption of integrated mangrove-shrimp cultivation could face several challenges that need to be addressed in order to realize substantial benefits from blue carbon sequestration.

Can greening of aquaculture sequester blue carbon?

Globally, blue carbon (i.e., carbon in coastal and marine ecosystems) emissions have been seriously augmented due to the devastating effects of anthropogenic pressures on coastal ecosystems including mangrove swamps, salt marshes, and seagrass meadows. The greening of aquaculture, however, including an ecosystem approach to Integrated Aquaculture-Agriculture (IAA) and Integrated Multi-Trophic Aquaculture (IMTA) could play a significant role in reversing this trend, enhancing coastal ecosystems, and sequestering blue carbon. Ponds within IAA farming systems sequester more carbon per unit area than conventional fish ponds, natural lakes, and inland seas. The translocation of shrimp culture from mangrove swamps to offshore IMTA could reduce mangrove loss, reverse blue carbon emissions, and in turn increase storage of blue carbon through restoration of mangroves. Moreover, offshore IMTA may create a barrier to trawl fishing which in turn could help restore seagrasses and further enhance blue carbon sequestration. Seaweed and shellfish culture within IMTA could also help to sequester more blue carbon. The greening of aquaculture could face several challenges that need to be addressed in order to realize substantial benefits from enhanced blue carbon sequestration and eventually contribute to global climate change mitigation.

Under pressure: Investigating marine resource-based livelihoods in Jakarta Bay and the Thousand Islands.

Jakarta Bay, next to the Jakarta Metropolitan Area with around 30 million inhabitants, is facing extreme pollution. Although local coral reefs are degraded and marine resources heavily exploited, they provide livelihoods for millions of people. This study investigates anthropogenic pressures on local fisheries resources and associated livelihoods. Questionnaire surveys were conducted in 15 coastal communities (10 coastal neighborhoods in Jakarta Bay on the mainland and 5 of the offshore Thousand Islands). The most economically valuable species were Caesio cuning (Redbelly yellowtail fusilier) on the islands and Rastrelliger kanagurta (Indian mackerel) on the mainland. Over 80% of all interviewed fishermen regarded the current state of marine resources as declining, mainly due to pollution and overexploitation. While perceptions of declining resources were equally high on the islands and the mainland, pollution was listed as the principal cause of degradation significantly more on the mainland. Findings are discussed in the context of coastal livelihood vulnerability.

Association of caries increment in preschool children with nutritional and preventive variables.

OBJECTIVES: The aim of the present study was to evaluate the influence of various risk factors on dental caries increment in deciduous teeth of preschool children over 2.5 years. MATERIALS AND METHODS: A longitudinal study was carried out in kindergartens in two German counties in Northern Hesse. At baseline examination in 2006-2007, the mean age of the children was 3.5 years. Caries experience was recorded according to WHO standards. Information about feeding practices during early childhood and preventive measures were collected by a structured questionnaire for each child. RESULTS: Three hundred ninety-five (69.8%) of the 566 children showed no caries increment. A caries increase of 1 to 10 dmf-teeth was exhibited by 171 children (30.2%). The mean dmf-t increment amounted to 0.75. The bivariate analysis revealed that the consumption of sugary food and beverages had a negative impact on oral health. Early start of toothbrushing, use of fluoridated children's toothpaste, and frequent toothbrushing exerted a positive influence on dental health. Stepwise backward logistic regression analysis confirmed that a high social status has a significant positive impact on dental health (p = 0.028), whereas the consumption of sugary food and beverages was significantly associated with a higher dental caries increment (p = 0.004). CONCLUSION: Obviously, it is not possible to limit the caries increment in children of low socioeconomic status as successfully as in children of high socioeconomic status. CLINICAL RELEVANCE: There must be a stronger focus on families of low socioeconomic status when preventive measures are performed on groups or individuals.