THE AQUACULTURE FUTURE & RESEARCH

AQUAPONICS – INTEGRATING AQUACULTURE AND HYDROPONICS

Aquaponics is a symbiotic integration of two mature food production disciplines: (i) aquaculture, the practice of fish farming; and (ii) hydroponics, the cultivation of plants in water without soil.

Aquaponics combines the two within a closed recirculating system. A standard recirculating aquaculture system filters and removes the organic matter (“waste”) that builds up in the water, so keeping the water clean for the fish. However, an aquaponic system filters the nutrient‑rich effluent through an inert substrate containing plants. Here, bacteria metabolize the fish waste, and plants assimilate the resulting nutrients, with the purified water then returning to the fish tanks. The result is value-added products such as fish and vegetables as well as lower nutrient pollution into watersheds. 

Aquaponics has the potential for higher yields of produce and protein with less labour, less land, fewer chemicals and a fraction of the water usage. Being a strictly controlled system, it combines a high level of biosecurity with a low risk of disease and external contamination, without the need for fertilizers and pesticides. Moreover, it is a potentially useful tool for overcoming some of the challenges of traditional agriculture in the face of freshwater shortages, climate change and soil degradation. Aquaponics works well in places where the soil is poor and water is scarce, for example, in urban areas, arid climates and low-lying islands.

However, commercial aquaponics is not appropriate in all locations, and many start-ups have failed. Before investing in large-scale systems, operators need to consider all factors carefully, especially the availability and affordability of inputs (i.e. fish feed, building and plumbing supplies), the cost and reliability of electricity, and access to a significant market willing to pay premium prices for locally produced, pesticide-free vegetables. Aquaponics combines the risks of both aquaculture and hydroponics, and thus expert assessment and consultation are essential.

To support aquaponic development, FAO has produced a technical manual on small-scale aquaponic food production.1 At the Thirty-first Session of the FAO Committee on Fisheries (June 2014), four Members (the Cook Islands, Indonesia, Kenya and Mexico) cited aquaponics as an opportunity warranting greater attention. Moreover, a related side event presented yumina, a form of aquaponics used across Indonesia. As a follow-up, Indonesia, with support from FAO and the South–South Cooperation team, held a regional technical workshop on aquaponics in late 2015 to train trainers from countries around the world. Separately, FAO also convened a training workshop on aquaponics for countries in the Near East and North Africa region.

In the future, the agriculture sector will need to produce more with less. Following the principles of efficient resource use, synergistic benefits can be realized by integrating food production systems and reducing inputs, pollution and waste, while increasing efficiency, earnings and sustainability. Thus, aquaponics has the potential to support economic development and enhance food security and nutrition through efficient resource use, and become an additional means of addressing the global challenge of food supply.

AQUACULTURE MAPPING AND MONITORING

Inventories and monitoring of aquaculture facilities provide decision-makers with important baseline data on production, area boundaries, and environmental impacts. Mapping facilitates such work and improves the effectiveness of interventions for disaster assessment and emergency preparedness.

The mapping of aquaculture facilities can be performed accurately, regularly (i.e. minutes, days, months or years) and at selected scales by remote sensing. Remote sensing – using satellites, aircraft, drones or fixed sensors – enables observations of vast and often remote or inaccessible areas at a fraction of the cost of traditional surveys. It provides a large range of observation data that complement and extend data acquired from in situ observations to support aquaculture management.

Challenges for aquaculture mapping include:

(i)                  limited awareness of its benefits for decision-makers and technical personnel;

(ii)                limited knowledge on how to conduct inventories and analysis;

(iii)              limited number of innovative mapping applications;

(iv)              limited human resources, infrastructure and financing.

FAO assists countries in recording the location and type of aquaculture facilities so they can improve their aquaculture zoning, site selection and area management. These facilities and their evolution can be assessed against locations of sensitive ecosystems and habitats to highlight potential impacts. They can also be linked to the licensing process to identify unregistered or illegal facilities. FAO’s National Aquaculture Sector Overview map collection provides a spatial inventory of aquaculture with attributes including species, culture systems and production.1 Based on Google Earth/Maps technology, its aim is to develop ways to assist developing countries and so encourage them to conduct their own inventories, at minimal cost, as part of their strategic planning for sustainable aquaculture development. Some have already begun creating their own farm-level inventories by creating atlases and/or Web mapping applications.

Google Earth is a good starting point for spatial inventories of aquaculture as it makes high-resolution data (e.g. satellite images or historical aerial photographs) freely available to the general public, without requiring any remote-sensing expertise. Despite some limitations (e.g. obsolete/undated imagery or other layers, insufficient resolution for some aquaculture applications, and incomplete coverage owing to cloud cover), such mapping applications should be the first stop in a spatial data search where base maps and specialized layers are lacking. However, ground-based data gathering remains important for validation, and here global positioning systems (GPS) are essential for digitally recording the location of aquaculture facilities and assessing the accuracy of remote-sensing sources. More advanced approaches based on image analysis require the use of geographic information systems (GIS) or remote-sensing software and access to satellite images in their original format. Digital data (such as from remote sensing) pertaining to any aspect of aquaculture can be assembled in a GIS. These systems perform a wide range of spatial and statistical analyses, providing informed answers to aquaculturists, local managers, government officials and other groups promoting sustainable aquaculture development.

Advances in remote-sensing and mapping technologies and spatial analyses will enable improved and more informed opportunities in aquaculture, especially as these technologies and analyses become increasingly powerful, cheaper and more accessible to all. In this respect and thanks to partnerships mobilized through projects around the world, FAO continues to promote the adaptation and tailoring of innovative methodologies and capacities to facilitate concurrent access to remote sensing, field data-collection devices (e.g. GPS, smartphones and tablets), GIS and spatial analysis by aquaculture stakeholders.

AQUACULTURE AND CLIMATE CHANGE

The Issue: Climate change will have a range of impacts on aquaculture.

Possible solutions

There are practical adaptation measures (“no regret” actions) that can effectively address climate variability and trends at the farm, local and national levels and even at a global scale. With these measures, fish farmers and other local stakeholders can play a proactive role in addressing both long-term changes/trends and sudden changes (e.g. extreme weather events):

Ø  aquaculture zoning to minimize risks (for new aquaculture), and relocation to less exposed areas (existing farms); „„

Ø  appropriate fish health management; „„

Ø  increasing efficiency of water use, water recycling, aquaponics, etc.; „„

Ø  increasing feeding efficiency to reduce pressure and reliance on feed resources; „„

Ø  developing better-adapted seed stock (e.g. tolerance to lower pH, broader salinity resistance, faster-growing strains and species, and other attributes); „„

Ø  ensuring high-quality, reliable hatchery production to facilitate outgrow in more stressful conditions, and to facilitate rehabilitation of production after disasters; „„

Ø  improvement of monitoring and early warning systems; „„

Ø  strengthening farming systems, including better holding structures (e.g. sturdier cages, depth-adjustable cages [for fluctuating water levels], deeper ponds) and management practices; „„

Ø  Improving harvesting methods and value addition.