1 Marine Food Systems and Aquaculture PDF

1 Marine food systems and aquaculture Learning outcomes of the course Define marine food systems, and key concepts and approaches related to marine food systems, such as sustainability, circularity, social license to operate Recognize how different marine...

1 Marine food systems and aquaculture Learning outcomes of the course Define marine food systems, and key concepts and approaches related to marine food systems, such as sustainability, circularity, social license to operate Recognize how different marine food systems can contribute to socially and environmentally sustainable food provisioning Apply environmental and social indicators for sustainability assessment of marine food systems Discuss trade-offs and synergies between different marine food systems in terms of environmental impact/contribution, human nutrition and social wellbeing Design strategies for transitioning marine food systems to meet the growing demand for sustainable, healthy and socially equitable (sea)food production Introduction to (marine) food systems Define (marine) food systems What is a system? Network of integrating components → form together a complex whole The relationship among components = key component of a system What is a food system? All the elements + activities that relate to Production Distribution Preparation Consumption of food Also the outputs of these activities → includes socio-economic + environmental outcomes A food system is a Socio-Ecological System (SES) = systems that combine human social systems, with natural earth systems + earth surface processes, to fulfill food needs of human societies Food systems have changed over time 1 Marine food systems and aquaculture 1  Past → more traditional food systems Small scale Local Seasonal dependent Changes over the years (during industrialisation) → modern food systems Large scale Industrillised/specialized Global (production + sales can be on 2 totally different locations) Not the whole world has these modern food systems Global food system map Many activities are connected to each other → complicated to understand the overview Food system map (simplified) → consists of 3 main components Activities (e.g. production, storage/distribution of the food, food consumption) Drivers (socio-economic + environmental) Increase in population → increases demand for food Environmental → biodiversity losses Outcomes Socio-economic (e.g. livelihoods, incomes) Food security + nutrition Environmental Interaction between the components, is what a system makes a system 1 Marine food systems and aquaculture 2  Marine food systems Resulting in different types of seafood Finfish (e.g. cod, salmon, tuna, flatfish) Molluscs (e.g. squid, mussels, oysters) Crustaceans (e.g. shrimp, lobster, crab) Echinoderms (e.g. sea cucumber, sea urchins) Aquatic plants (e.g. seaweeds) How do we get our seafood? Fishery = capture of wild stock Aquaculture = production in confined cages/tanks/other production systems Fisheries increased until 1990s → after 1990s it levelled off Aquaculture increases since 2000s Now: 50/50 of fisheries/aquaculture of animal production Total aquaculture > fisheries when taking production of aquatic plants into account Prediction = aquaculture will keep increasing Why is there a demand for seafood? Healthy diets (e.g. omega-3) Livelihoods 800 million people depend on blue food systems → aquaculture + fisheries Food security Enough + accessible food Boundaries for production on land → large area of oceans On average less environmental pressure (compared to for example beef) Depends on what marine system we’re looking at 1 Marine food systems and aquaculture 3  Interest in politics Blue growth = using oceans to provide healthy diets We do have to realize that all our human activities have an impact Environmental stressors of blue food Aquaculture Land use Nitrogen + phosphorus emission Freshwater use Genetic pollution Antibiotic resistance Disease spread Fisheries Stock/species depletion Megafauna by-catch Food web alterations Ghost fishing By-catch trawling Socio-economic challenges of blue food Working conditions Slavery Visual pollution (aquaculture) Biodiversity + animal welfare (fisheries) 1 Marine food systems and aquaculture 4  Sustainable marine food systems Balance impacts with positive aspects → sustainability Holistic approach → if 1 thing is changed, everything else might change → avoid unintended consequences Scale (spatial + time) Understand sustainability and circularity concepts Sustainable development = development that meets the needs of the present without compromising the ability of future generations to meet their own needs Development is Environmentally non-degrading Economic viable Socially acceptable What is environmental sustainability? Not exceeding the regenerative carrying capacity of the system Not exceeding the absorptive/assimilative carrying capacity of the system Planetary boundaries 9 processes critical for maintaining the stability + resilience of the Earth = if we stay within these boundaries we can keep the state of the Earth in such a way that we can live on it, as we live on it now Preserving ecosystem services → benefits people obtain from ecosystems 1 Marine food systems and aquaculture 5  Provisioning services = all the products we can gain from the ecosystem Supporting services = all the functions that are provided by the ecosystem that support all the other services Regulating services = results of natural processes that can help us with purification (e.g. water flow, nutrient cycling) Cultural services = non-material benefits from the environment (e.g. jobs, tourism, recreational fishing) Circularity Circular economy → repair, reuse, recycle all of the waste products → 0 waste emissions 5 ecological principles for efficient biomass use → guide us towards a circular economy Safeguarding + regenerating health of ecosystem Avoid production of non-essential biomass + losses of essential ones Prioritize use of biomass to basic human needs Recycle unavoidable losses Minimize overall energy use + use renewable energy Introduction to food provisioning via aquaculture Understand the diversity in aquaculture After 2000 → increase in aquaculture Since population is growing → higher global demand Aquaculture types Freshwater Brackish water Saltwater (marine) Difference in value → higher value of freshwater aquaculture production Also increase in species that are cultivated in aquaculture practices Global aquaculture production → highly diverse systems Sea cages (e.g. salmon, seabass) Rope cultivations (e.g. bivalves, seaweeds) Recirculating Aquaculture Systems (RAS) → land based Water is purified by the use of bacteria → water can be used multiple times before discarded Pond aquaculture Extensive → lowest production per ha + specie produced can rely on natural food system in the pond Semi-intensive → mediate production per ha + combination between formulated diet + natural food system Intensive → highest production per ha + specie produced has a formulated diet In 2019 → 79% of fish + crustaceans are produced in ponds 1 Marine food systems and aquaculture 6  Seafood → trophic levels 1. Autotrophs 2. Herbivores 3. Carnivores 2 types of aquaculture Fed aquaculture Intensive (high production per ha) External feed source needed In marine aquaculture mainly finfish + crustacean Intensive farm management Link with other food systems → mainly through feed Aquaculture + fisheries (fish from fisheries can be used in diet) Aquaculture + agriculture (part of diet consists of plants) Aquaculture + (marine) aquaculture (seaweeds can be part of diet) Fish meal and fish oil fish in the fishmeal/oil (kg) Fish in - Fish out (FIFO) = kg of fish harvested/gain  ​ Lower Fish In Fish Out indicator = more sustainable Fish Conversion Ratio (FCR) = amount of feed distributed kg of fish harvested/gain → fish are more efficient than land animals (since ​ fish are cold blooded, less energy needed to keep body warm + extrete nitrogen directly as ammonia + less energy on resisting gravity) FCR does not look at difference in feed content + edible portion animal + nutritional quality product Non-fed aquaculture (e.g. autotrophs, since they get their feed from the environment) Low-trophic aquaculture Extensive (low production per ha) No input of feed No input of medicines Limited farm management → farmers don’t need to go to the farm every day Extensive species Removes nutrients/food from water → biofilter → eutrophication control, carbon capture 1 Marine food systems and aquaculture 7  Understand some of the environmental challenges in aquaculture Fed aquaculture → feed impact (farm scale) Feed derived waste Uneated feed (minority) Faecal losses (solid) = majority → seafloor impact Non-faecal losses (dissolved) Branchial + urinary losses (nitrogen) → released via gills Respiration Multiple farms → eutrophication risk Fed aquaculture → feed production (global scale) Main contributor to GHG emissions + land use for most species Can also be the main source of water use Environmental performance of different aquaculture species Extractive species generally have a lower footprint → because they do not require food Lowest foodprint from seaweeds + bivalves Negative values for nitrogen + phosphorus possible (figure below)? Species take up nitrogen + phosphorus Relatively take up > production Non-fed aquaculture → potential environmental impact Extractive species → extra nutrients from the environment It’s about the balance Within carrying capacity Eutrophication control Carbon sequestration Beyond carrying capacity Nutrient depletion Competition with phytoplankton 1 Marine food systems and aquaculture 8  Aquaculture → ecological benefits Regenerative aquaculture = restoring ecosystems via aquaculture Focus on natural benefits + less on food To summarize Provisioning of food via aquaculture is highly diverse Therefore, the challenges are highly divers But, there are also diverse opportunities 1 Marine food systems and aquaculture 9