Among the many achievements, the major achievement in the past 200 years in the general field of agriculture is soil-less farming also called hydroponics. The hydroponics become further advanced, in the mid-19th century by integrating with the aquaculture (rearing of fish in a tank) now this amalgamation called Aquaponics. The Aquaponics is the new way of farming in Nepal. In Nepal, it is at the rudimentary stage of development with many people distant from its cognizance and practice. Although it has been a boon to the urban farming in the semi-arid region by analyzing the adaptation rate, the water scars area like Kathmandu is oblivion to the 19th-century development.
Benefits:
The excreta and nitrogenous wastes produced by the fish along with water in aquaculture tank is pumped to the hydroponics tank through the hose, the excreta works as the nutrient medium in the hydroponics tank which vegetables utilize for the growth and development, and again water is recycled back to the aquaculture tank. The unique benefit of aquaponics is circulation of water and nutrients, this yields less water and nutrient loss, except those utilized by plants, and few portions lost during evapotranspiration so maximum water and nutrient efficiency are reached, which is the main reason to adopt in water scars areas. Similarly, the Sustainable Development Goal (SDG) 6.4 has called for efficient use of water. To pull off the plan, the aquaponics can be the major arsenal to combat the surging water crisis in agriculture around the world.
SDG source:
http://www.un.org/waterforlifedecade/waterandsustainabledevelopment2015/open_working_group_sdg.shtml
Likewise, with no soil and few nutrient media as the substrate, there exists no chance of soil-borne pests and diseases. In fact, after sterilization, the soil fewer media can be reused. From the research, the output produced from the nutrient substrate is better off than that grown in soil. With no soil-borne pests and diseases, which accounts for more than 25 percent yield loss in terrestrial plants get wiped out. Likewise, the weeds infestation is rare, except if the seeds are contaminated. Moreover, the cost incurred for management of maladies, pests, and weeds gets reduced. Above all, the risk incurred by lethal pesticide use to the human health and environment becomes less—both during application and after feeding pesticide-laced vegetables. So, the output is pesticide less and are of high value.
Fishes are the prerequisite if our main objective is pesticide-free vegetables. Nevertheless, the fishes in the aquaponics mostly are, in fact, also without the harmful chemical, unless we use them (to save fish from disease). Any breed of freshwater fish (tilapia, trout, catfish) thrives in the aquaponics, in the congenial temperature. However, the continuous agitation of water is necessary for the tank to reach the minimum oxygen level required for fish to survive and thrive.
Fish is an increasingly important source of global protein production. Fishes from the aquaculture account for almost one-half of the fish eaten in the world, with aquaculture production matching capture fisheries landings for the first time in 2012. Source FAO (http://www.fao.org/3/a-i5555e.pdf) page number 15-16 graph.
Aquaculture has the potential to decrease the pressure on the world’s fisheries and to significantly reduce the carbon footprint of less-sustainable terrestrial animal farming systems in supplying humans with animal protein.
Until 2014, 54 percent of the world’s population lived in urban areas, a proportion that is expected to increase to 66 percent by 2050. Similarly, by 2050 the world population is expected to reach 9 billion, the upheaval task to feed 9 billion that is almost 2 billion extra population, an increase by 30% from the current population, where still 795 million people are undernourished worldwide today, is not a cupcake.
(Data source:
http://www.un.org/en/development/desa/news/population/world-urbanization-prospects-2014.html)
Considering that many places in the world are combating hunger and struggling to support the basic need for food and safe drinking water to their populace that is clearly a big problem. To combat, we need to adopt the genial techniques to feed the people. To solve the surging demand for foods, we need to produce locally. In Nepal, the growing vegetables demand and surging market price of vegetables( currently we are facing the abnormally high price) the aquaponics could be handy, if we had adopted earlier, however, we are obscure about the practice, still this could be the next generation farming to get a combo benefit of fish and green veggies.
Constraints
There is no doubt that aquaponics is a sophisticated way of farming, which requires some initial cost to set up the required items for running of aquaponics. Similarly, to keep the system running smooth electricity supply is required to pump the water back and forth between the tanks. So, in the areas where there are frequent power cuts is not a viable ground due to over cost for backup power. At a time when the country is facing no frequent power-cuts, the erratic power supply does not stymie as it used to, a few years back. Nonetheless, the benefits reaped from the aquaponics pays off all the constraints to operate the aquaponics.
In aquaponics, diseases, and pests in vegetables are rare, but fishes are susceptible to the common disease like ich (Ichthyophtirius) and fin rot and are the most likely problems with fish, regardless of the species. Ich looks like white spots growing all over the scales of fish, and fin rot is exactly as it sounds. As both develop in dirty water, so the best approach is to keep a clean tank in the first place and decrease the overcrowding of fish.
(from aquaponics book and consulting with experts and early adopter of this new technique who is also our teacher.)
In currently existed and newly formed metropolitan, sub-metropolitan, and municipality, the local government and the federal government should come up with the congenial plan and promote aquaponics. To make the cities self-reliant on the production of vegetables and fishes, before the city populace are subjugated by the pesticide-laced market vegetables—both in short run( due to the high cost of veggies and fish) and long run( medical expenses to cover the consequences by eating pesticide-laced veggies). Why fully depend on others when we can reap fish and vegetables at once?
Susan Thapa is currently working as National Communication Coordinator at IAAS NEPAL and Local Committee Director of IAAS HICAST
