Aquatic resources encompass everything humans extract, harvest, or benefit from in oceans, rivers, lakes, and coastal wetlands. That includes the obvious, like fish and drinking water, but also minerals from the seafloor, energy generated by waves and temperature gradients, pharmaceutical compounds derived from marine organisms, and less tangible services like carbon storage and storm protection provided by coastal ecosystems. In 2022 alone, fishing and aquaculture directly supported more than 61 million workers worldwide, and more than 80 percent of global trade by volume travels by sea. The category is far broader than most people realize, and the pressures on it are mounting from multiple directions at once.
Wild Fisheries and Why They Still Matter
When people think of aquatic resources, fish come to mind first, and for good reason. Fish are rich in essential micronutrients, minerals, fatty acids, and proteins, and they provide more than 1.5 billion people, especially in low-income food-deficit countries, with roughly a fifth of their average animal protein intake.1Philosophical Transactions of the Royal Society B. Food security and marine capture fisheries: characteristics, trends, drivers and future perspectives For the countries most dependent on fish to meet their populations’ nutritional needs, wild capture fisheries remain the dominant supplier, not aquaculture. Contrary to a popular narrative that all fisheries are on the brink of collapse, their sustainability varies enormously by region and species, though securing it does require serious ongoing effort.2PubMed Central. Innovations in capture fisheries are an imperative for nutrition security in the developing world
Wild-catch fisheries do not just produce food directly. Of the roughly 144 million tonnes produced globally by capture fisheries and aquaculture in 2006 (a benchmark year in the research), about 110 million tonnes went to direct human consumption, while 33 million tonnes were processed into fish meal for aquaculture feed, cattle, pig, and poultry farming.1Philosophical Transactions of the Royal Society B. Food security and marine capture fisheries: characteristics, trends, drivers and future perspectives That indirect channel means the ocean’s biological productivity ripples through land-based food systems in ways that do not always show up in the conversation about aquatic resources. Destructive and illegal fishing, however, can alter food webs and ecosystem structure, eroding the productivity and resilience that these systems depend on.
Aquaculture and Its Growing Footprint
Aquaculture, the farming of fish, shellfish, seaweed, and other aquatic organisms, has expanded rapidly to meet rising global demand for seafood. It is now considered critical to global food and nutrition security, but that growth has come with environmental baggage. A comprehensive sustainability assessment found that the overall sustainability of global aquaculture is low, with an average composite score of just 26 out of 100 across the countries studied. No country achieved a high sustainability score, and roughly 80 percent of countries had at least two sectors (among food, energy, water, and carbon) falling into the lowest sustainability tier.3Resources, Conservation and Recycling. Environmental sustainability and footprints of global aquaculture
The environmental impacts of aquaculture include significant energy use, water consumption, and greenhouse gas emissions. In 2018, global aquaculture production accounted for roughly 261 million tonnes of greenhouse gas emissions, consumed about 123 cubic kilometers of water, and used over 1,765 thousand terajoules of energy.3Resources, Conservation and Recycling. Environmental sustainability and footprints of global aquaculture Eutrophication, the over-enrichment of water with nutrients that triggers algal blooms and oxygen depletion, is another well-documented consequence.4Aquaculture. Environmental impacts of existing and future aquaculture production: Comparison of technologies and feed options in Singapore The challenge is not whether aquaculture should expand to feed a growing population; the question is whether it can do so without undermining the aquatic systems it depends on.
Marine Biotechnology and Genetic Resources
Beyond food, the ocean is an enormous pharmacological and industrial library that scientists have only recently begun to catalog. Over the last several decades, increasing attention has focused on the commercial potential of marine genetic resources for pharmaceuticals, cosmetics, agriculture, and industrial biotechnology. Since the first reports in the 1950s, roughly 23,500 natural products have been identified from marine organisms, with the catalog growing at about four percent per year.5United Nations iLibrary. Marine genetic resources and bioprospecting in the Western Indian Ocean Only a small fraction of those compounds have reached commercialization, but the pipeline is wide. Marine-derived compounds are already used in anticancer drugs and antiviral medications, and the projected market for marine biotechnology products was expected to reach nearly five billion US dollars.
This kind of bioprospecting raises thorny questions about who benefits. Most marine genetic resources are found in the waters of developing countries, but the research capacity and patent filings concentrate in wealthier nations. International negotiations under the United Nations have tried to address this imbalance, and the topic remains a flashpoint in ocean governance discussions.
Freshwater as the Invisible Aquatic Resource
Freshwater is the aquatic resource people interact with most and think about least in this context. Agriculture alone is responsible for close to 70 percent of all freshwater withdrawals worldwide, making it the most water-intensive sector by a large margin.6PubMed Central. Water scarcity in agriculture: An overview of causes, impacts and approaches for reducing the risks The rest is split among industrial uses, energy production (particularly cooling for thermal power plants), and domestic consumption. Water scarcity is intensifying in many regions due to population growth, land-use changes, and shifting rainfall patterns, which means that freshwater is increasingly treated not just as an input to agriculture but as a contested resource in its own right.
Desalination has emerged as a partial solution, particularly in arid coastal regions. Seawater reverse osmosis plants now operate in dozens of countries, converting saltwater into drinking water. But the process produces hypersaline brine that, when discharged into the sea, can cause real ecological damage. This brine typically carries salinity levels one and a half to two and a half times higher than the surrounding seawater, along with residual treatment chemicals and trace metals. It can alter pH, reduce dissolved oxygen, and disrupt the physiology of marine organisms in the discharge zone.7Current Opinion in Environmental Science & Health. Impact of brine discharge from desalination plants on marine ecosystems: A review The dense brine sinks to the seafloor and can creep along the bottom for kilometers, reaching up to five kilometers from the discharge point and potentially spreading over the seabed for tens of kilometers, impairing nutrient fluxes from sediment to the water column along the way.8PubMed. Impacts of Desalination Brine Discharge on Benthic Ecosystems Freshwater production, in other words, can come at the expense of other aquatic resources.
Energy from Aquatic Systems
Water is one of humanity’s oldest energy sources, and the range of technologies that tap it keeps expanding. Each involves distinct trade-offs, and treating them as a single category obscures more than it reveals.
Hydropower
Hydropower dams generate a large share of the world’s renewable electricity, but they fundamentally reshape the rivers they occupy. On the Columbia River in the Pacific Northwest, for instance, the conversion of a free-flowing river into a chain of slack-water reservoirs has shifted the evolutionary pressures on salmon. Conditions that once favored fish capable of long-distance upstream migration against strong currents now favor fish that can navigate lakes and find fish ladders. Juveniles must survive passing through multiple dams or being physically collected and transported around them. The dams have also increased the metabolic cost of migration, reducing the energy salmon have available for reproduction and favoring life histories that skip migration altogether.9PubMed. Evolutionary responses by native species to major anthropogenic changes to their ecosystems: Pacific salmon in the Columbia River hydropower system Hydropower illustrates a recurring tension with aquatic resources: extracting energy from a water system changes it in ways that ripple through the biology for generations.
Offshore Wind
Offshore wind energy is expanding rapidly, and newer floating turbine technology now makes it possible to install wind farms in waters too deep for fixed platforms. This is a significant step for renewable energy portfolios, but the ecological concerns are real and distinct from those of land-based wind. Floating turbines introduce mooring lines and dynamic cables that can entangle marine life or accumulate debris that snares animals secondarily. Seabirds may be attracted to the structures as perching sites, increasing their collision risk. The anchoring systems and cable movements can also degrade the seafloor habitat beneath them.10PubMed. Potential impacts of floating wind turbine technology for marine species and habitats Large-scale expansion is planned in over a dozen countries, and researchers are still working to understand the cumulative effects of hundreds of turbines in a single marine area.
Tidal, Wave, and Ocean Thermal Energy
The ocean holds enormous energy beyond wind. Tidal streams and waves alone have been estimated at over 30,000 terawatt-hours per year in theoretical global resources.11Renewable and Sustainable Energy Reviews. Comparison study of tidal stream and wave energy technology development between China and some Western Countries Tapping even a fraction of that would be substantial, though both technologies remain largely in the pilot and demonstration phase. The engineering challenges are formidable: saltwater corrodes equipment, storms destroy it, and the energy density of waves and currents varies widely by location and season.
Ocean thermal energy conversion, or OTEC, takes a different approach entirely. It exploits the temperature difference between warm surface water and cold deep water to generate electricity.12Energy Conversion and Management: X. A comprehensive review on ocean thermal energy conversion technology: Thermodynamic optimization, multi-energy integration, and byproduct utilization This works best in tropical regions where the surface-to-depth temperature gradient is largest. OTEC has been studied since the 1880s but has never scaled up commercially, partly because the efficiency of the thermal cycle is inherently low and the infrastructure costs are high. Recent interest has revived around combining OTEC with desalination and deep-water aquaculture, making the economics more favorable by producing multiple outputs from a single system.13PubMed Central. An assessment of ocean thermal energy conversion resources and climate change mitigation potential
Offshore Oil and Gas
Fossil fuels extracted from beneath the seafloor remain among the most economically significant aquatic resources, even as the energy transition accelerates. Offshore drilling has been practiced for over a century, and the industry’s environmental track record is mixed. Historical studies of drilling mud and cuttings discharged from more than 21,000 wells drilled offshore and in US coastal waters concluded that these discharges had not caused detectable short- or long-term environmental damage under normal operations, with discharged materials diluting rapidly in seawater.14Offshore Technology Conference. Environmental Aspects Of Drilling Muds And Cuttings From Oil And Gas Extraction Operations In Offshore And Coastal Waters That conclusion, however, applies to routine operations and does not account for catastrophic spills, which have devastated marine ecosystems in well-documented cases. Routine and catastrophic are two very different risk categories, and conflating them distorts the picture in either direction.
Minerals and Deep-Sea Mining
The seafloor holds vast deposits of manganese nodules, polymetallic sulfides, and cobalt-rich crusts that contain metals critical to electronics and battery technology. Interest in harvesting these has surged as land-based mines face depletion and political complications. The ecological stakes, however, are poorly understood. Research on sediment from the Clarion-Clipperton Zone, a prime target for deep-sea nodule mining in the central Pacific, found that the marine copepod Tigriopus californicus showed dose-dependent drops in growth and reproduction when exposed to the sediment, along with reduced mating success, lower pregnancy rates, and impaired offspring viability.15Environmental Science & Technology. Ecological Impacts of Deep-Sea Mining Waste on Marine Algae and Copepod Tigriopus californicus The deep ocean is among the least-studied environments on Earth, and species that live there often reproduce and recover slowly. Mining activity would stir up sediment plumes that drift far beyond the extraction site. Whether commercial-scale extraction can occur without lasting damage to these ecosystems is a question science has not yet answered with confidence.
Ecosystem Services You Cannot Harvest
Some of the most valuable aquatic resources are not things you take out of the water. They are functions the water and its ecosystems perform for free, functions that would cost enormous sums to replicate with human infrastructure.
Blue Carbon
Mangroves, seagrasses, and salt marshes capture and store carbon dioxide from the atmosphere at rates that, per unit area, far exceed most terrestrial forests. These “blue carbon” ecosystems are vital for biodiversity and play a significant role in climate regulation.16PubMed. Blue carbon ecosystems for hypoxia solution: how to maximize their carbon sequestration potential Their value extends beyond carbon sequestration, though. In New Zealand, researchers quantifying the monetary worth of these ecosystems found that while carbon storage was the most valuable service provided by mangroves, saltmarshes were most valuable for waste treatment, and seagrasses for their existence and bequest value, essentially their worth to people who may never visit them but value knowing they exist.17New Zealand Journal of Marine and Freshwater Research. Beyond Blue Carbon: Estimating the Value of Ecosystem Services Provided by Coastal Wetlands in Aotearoa New Zealand When these habitats are destroyed, the stored carbon is released back into the atmosphere, turning a climate solution into a climate problem.
Coastal Protection
Coral reefs, seagrass beds, and mangrove forests work together to blunt wave energy, reduce flooding, and stabilize shorelines. Research has shown that while mangroves alone can deliver most of the coastal protection benefits, corals and seagrasses moderate the nearshore wave climate in ways that reduce erosion risk, stabilize the seabed offshore of the mangroves, and reduce currents enough to let mangrove populations recruit and sustain themselves.18PLoS ONE. The Power of Three: Coral Reefs, Seagrasses and Mangroves Protect Coastal Regions and Increase Their Resilience The three habitats together protect coastlines better than any one alone. This is not a minor benefit. Hundreds of millions of people live in low-lying coastal areas, and replacing the storm protection provided by a healthy fringing reef with concrete seawalls would cost billions. Yet reef destruction, coastal development, and mangrove clearing continue to dismantle these natural defenses.
What Threatens Aquatic Resources
The threats are multiple and interact with each other in ways that make predicting outcomes difficult. Nutrient pollution from agriculture is one of the most widespread. Fertilizer runoff carried by rivers fuels algal blooms in coastal waters. When those blooms die and decompose, microbial activity consumes the dissolved oxygen in bottom waters, creating hypoxic “dead zones” where little can survive. Dead zones have been reported in more than 400 systems worldwide, covering a combined area of more than 245,000 square kilometers.19PubMed. Spreading dead zones and consequences for marine ecosystems The Gulf of Mexico dead zone, fueled by nutrient runoff from agriculture in the Mississippi River basin, is among the most studied examples, but the phenomenon is global and growing.20PubMed Central. The dead zones: oxygen-starved coastal waters
Plastic pollution adds another layer. Experiments have shown that high levels of plastic pollution significantly reduce the decomposition rate of kelp and eelgrass, by roughly 27 and 36 percent respectively compared to controls, and slow the release of nitrogen from decaying plant material.21PubMed. The influence of plastic pollution and ocean change on detrital decomposition Decomposition and nutrient cycling might sound abstract, but they underpin the food webs that fisheries depend on. Higher seawater temperatures, meanwhile, speed up decomposition but alter the nutrient balance in different ways. The combination of warming oceans, acidification, and plastic accumulation is creating a set of interacting stresses that no single policy can address in isolation.
Recreational and Cultural Dimensions
Not all aquatic resource use is industrial. Recreational fishing, swimming, diving, and boating generate enormous economic activity and hold deep cultural significance for coastal and riparian communities worldwide. Recreational fisheries in particular sit at the intersection of human well-being and environmental health: when environmental degradation harms fish populations, it does not just affect ecosystems but also the people who depend on those fish for nutrition, livelihoods, culture, and well-being.22FACETS. A One Health perspective on recreational fisheries This connection is intuitive but often missing from policy frameworks that separate “environment” from “economy” as if they were unrelated ledgers.
Traditional Management and Governance
Modern marine governance tends to emphasize top-down regulation, marine protected areas, quotas, and spatial planning. But in many parts of the world, communities have managed aquatic resources sustainably for centuries using systems rooted in local ecological knowledge. In Werka Village in Indonesia’s Maluku Province, for example, the traditional practice of sasi governs the harvest of sea cucumbers by designating closed seasons and areas, enforced through community institutions rather than state law. Research has found that the practice’s success is driven by the integration of economic, social, and institutional factors, backed by strong support from indigenous communities and local authorities.23BIO Web of Conferences. Sustainable management of marine resources through customary practices: The implementation of sasi on sea cucumbers in Werka Village, Maluku Province These systems often outperform centralized regulation because they embed enforcement in social relationships and adapt to local conditions. The growing interest in integrating traditional ecological knowledge into formal marine spatial planning reflects a recognition that governance structures work best when they draw on multiple knowledge systems.
At the international level, the concept of a “blue economy” has gained traction as a framework for managing aquatic resources in a way that balances economic growth with environmental sustainability. Marine spatial planning, which allocates ocean areas for specific uses much the way zoning works on land, is being adopted across regions from Europe to Latin America. The idea is straightforward: fishing zones, shipping lanes, wind farms, conservation areas, and aquaculture sites all occupy the same ocean, and without some framework for managing their overlaps, each sector degrades the resource base the others depend on. Whether these planning efforts can keep pace with the speed of ocean industrialization is the open question.