Aquaculture - Horticultural Synergy in the Greenhouse

When humanity finally sheds the onerous and degrading spectre of starvation, it will be because we have decided not to treat food, and the resources needed to produce it, just like any other commodity, but have come to see food as a basic and universal human right. It will be because we have found ways to stabilize our numbers and to heal the planet’s deeply injured life-support systems. It will be because we have realized that only when none of us fears hunger can any of us truly find peace.

And it will be because we have returned to the efficiency of a plant-based diet, making it possible for more people to eat. It is increasingly obvious that environmentally sustainable solutions to world hunger can only emerge as people eat more plant foods and fewer animal products. To me it is deeply moving that the same food choices that give us the best chance to eliminate world hunger are also those that take the least toll on the environment, contribute the most to our long-term health, are the safest, and are also far and away the most compassionate toward our fellow creatures.

Reversing the spread of hunger will mean learning to create a world based on cooperation and on the affirmation of the human spirit. It will mean organizing our societies in ways that assure every person the chance to live a healthy and productive life in harmony with Nature. It will mean examining all of our public policies and personal lifestyles in the light of our desire to touch as many people as possible with a message of hope for a better world.

“The day that hunger is eradicated from the Earth there will be the greatest spiritual explosion the world has ever known. Humanity cannot imagine the joy that will burst into the world on the day of that great revolution.” (Frederico Garcia Lorca)

Aquaculture

Aquaculture is the practice of avoiding going to sea by raising fish in ponds, it was one of the most ancient of human preoccupations and we’re still not very good at it. Technically, you can do just about anything, but it’s not necessarily wise that you should. Modern aqua cultural practise is not the solution to world hunger, aquaculture in its present form produces for those that demand and are willing to pay the price.

Is Ocean Aquaculture or Marine Horticulture Sustainable? As many fish are harvested for fish meal as are created by aquaculture. Open Ocean Aquaculture is seen by many as a way that aquaculture could safely and economically expand. Seeing a limited supply of coastal waters which are not yet ruined, focus is now on utilizing the open ocean area, and developing submerged and partially-submerged galvanized pens capable of sustaining the more unpredictable and harsh conditions 5km or more off-shore. Risk of contamination by chemical and biological agents is greater in freshwater and coastal ecosystems than in open seas; stationed in deep water with strong currents, it is hoped that the ocean farm's wastes and other pollutants are unable to reach noticeably harmful concentrations. The sturdy cages are thought to be relatively escape-proof, reducing the chances of infecting and destroying wild populations. Furthermore, the cages are tended and monitored by automated feed buoys, so they appear to be cost-effective not requiring the employment of any (or many) people from the local population.. It is hoped that research may lead to widespread use of an allegedly environmentally, economically and socially “preferred” aquaculture system by 2012.

So what is sustainable Aquaculture?

Simple, traditional, sustainable aquaculture is that aquaculture which can be achieved without substantial inputs of energy, feeds and utilizing low density stocking rates of fish and without major environmental manipulations. Primary feeds are naturally produced. Major inputs are labour usually from the farmers family. Operations are characterized by intensive husbandry , low overal capital expenditures and continued production over a long period of time . Due to lower stocking levels the health of the fish is generally much hardier than with higher stocking levels due to less stress and less exposure to disease pathogens. Operating equipment is usually low powered aerators and/or recirculating pumps, if any.

In the most basic mode ponds are stocked and fish naturally produced are harvested by angling or netting. This is the lowest production mode, and when fish are produced without a predator to remove most of the natural fry produced the ponds will soon become over populated and the bulk of the fish will be stunted in size. Stocking ponds with all males is the simplest production method to produce a marketable crop. The fish can be harvested over a period of time allowing the fish to continue growing.

To this model, various techniques can be added to increase production: feeding of natural feeds, such as duckweed and greenwater. Adding fertilizers such as manures to produce phytoplankton. Growing plants that will reduce nitrates in the water (nitrates reduce fish growth rates) such as water hyacinths, water lettuce, best of all growing edible plants and herbs fed by a solar/wind powered pumping system for damp ground or paddy fields for wet ground or on floating rafts on water like a lake. All is food that can be harvested for human use.

Next-generation - build anywhere

Next-generation land-based recirculating aquaculture systems are based on land, completely enclosed, recirculate 97-99% of their effluent, and are more than 10 times more efficient than open pond systems. These Next-generation systems are being rapidly embraced in Asia and Europe as cleaner, more secure, and ultimately more profitable solutions. Unfortunately, these systems have been largely overlooked in the United States and the Americas
Aquaculture must Team up with Agriculture A number of scientists and ecological designers are experimenting with more inclusive and holistic agriculture-aquaculture systems in which the waste of one half of the system is recycled and used as the resource for the other half of the system. Through waste recycling, integrated aquaculture/agriculture systems can be used to treat aquaculture effluents, increase farm productivity through efficient resource utilization, spread financial risk through diversification and reduce system nutrient losses in a closed-loop system that is inherently more sustainable than either aquaculture or agriculture is alone. For example, a man named "Hero of the Earth" by Time magazine in 1999 and one of the 20th Century's top thirty-five inventors, Dr. John Todd has designed and manufactured a series of "living technologies," ecologically-based inventions that are aimed at the purification of water, sewage, lakes, rivers, etc., including aquaculture tanks that are self-sustaining and do not rely on the input of fish feed. Integrated system models are also being developed to determine the size and structure of agriculture and agriculture components that can be used to balance the input and output of the components for a sustainable system.

So where and when do the lights get switched on? Photoperiod Manipulation

All animals and plants can be manipulated this way, this is one reason why the Sun on Earth is so important.

Fish reach maximum weight following maturation by which time the texture of meat can be unpleasant and distasteful. Using artificial daylight such as sulphur plasma lighting to manipulate the photoperiod (Daylight intensity and duration) means that farmed fish have accelerated growth levels and can gain much weight before maturation ensuring the harvested meat is plentiful and well edible.