Threat or Opportunity for Aquaculture?
(An Article by Leslie Ter Morshuizen from Aquaculture Innovations)
How do we know this?
In the 20th century the global population tripled and currently 220 000 people are born daily. This population growth, along with industrialisation and urbanisation, has resulted in several countries facing serious water shortages. A direct result of this is that 50% of hospital beds are occupied by sufferers of poor water related conditions.
It may seem hard to believe, but globally more people have cellular phones than access to a toilet.
And water usage in agriculture? Well, 70% of freshwater resources are allocated to agriculture. Practical usage includes:
- 25 000 ℓ of water to raise 1 kg of beef
- 4 000 ℓ to raise 1kg of chicken
- 1 120 ℓ to produce a cup of coffee
- 125 ℓ to produce a sheet of paper (please don’t print this!)
As a result of this looming water crisis, social and government agencies are looking for ways in which to limit new water allocations, reduce the usage by existing users and improve the quality of effluent water. This is all in an effort to improve the availability of clean, healthy water.
Aquaculture is expanding rapidly to supply the increasing gap between the growing world population and the decreasing availability of wild caught fish. The industry faces opposition in both the freshwater and marine environments from parties who perceive the industry to contribute to the demand for freshwater or to pollute fresh and marine waters.
However, it requires only 50ℓ to raise 1kg of fish in a RAS.
If done properly, therefore, aquaculture has enormous potential to alleviate hunger and create wealth without harming the environment.
Several ways in which this can be done include:
- Using recirculating systems to reduce water usage to a minimum.
- Effluent waste water should be used for irrigation to remove the risk of fish or associated pathogens escaping, and to utilise the nutrients in this water.
- Using feeds which are based on plant rather than fish proteins and oils.
- Using treatments that are environmentally friendly, especially those that dissociate into harmless substances.
In comparison to the amount of water required to raise other forms of animal crops, aquaculture has a vital role to play in our global water crisis as an industry that can produce a healthy form of protein with minimal water usage.
For more information on Leslie and Aquaculture Innovations, visit their website at http://www.aquaafrica.co.za/