The increase in population and urbanization has resulted in increased need for food and water in India. Our lands have become water and nutrient scarce and continuous use of synthetic fertilisers has depleted soil diversity which is needed for crop production. Challenges such as soil-borne diseases, weeds, and soil infertility, associated with soil plant production have made the soil culture risky and at times undesirable. As a result of the need to produce more and good quality food, without further damage to the natural environment, there has been an exploration of soilless agricultural systems, most popular, these include aquaculture, hydroponic and recently aquaponics system.
Overview of Soilless Systems
In soilless production, plants are raised without using soil as a growth medium. The method of not using soil as a crop stand saves significant water because in soil systems water can leach into groundwater. There are various common and available soilless productions systems; these systems include hydroponic, aeroponics, aquaponics, vertical gardens and tunnel or greenhouse aquaculture culture. Soilless production plays a critical and unique role in providing out of season food (meat and crop plants), herbs and flowers. While soilless systems have been a viable option to food and nutrition security in many countries there is little known or documented about these systems.
HydroponicsÂ
Hydroponics or hydroponic culture is a system where plants are grown in a soilless growth medium where all mineral nutrients delivered to plants are first dissolved in water before nutrients are available to plants. There are two types of hydroponic systems that are usually in use, these are liquid and aggregate production systems. The liquid hydroponic culture usually adopts nutrient film technique, and Deep-Water Culture (DWC)/floating rafts system. The growth medium hydroponic systems adopt various inert materials such as gravel, perlite, peat moss, peat, sawdust, rock wool, coconut fibre, grow stones, oasis cubes, vermiculite, coarse sand and expanded clay pellets.
Aquaponics
Aquaponics is a bio-integrated system that links recirculating aquaculture with hydroponic vegetable, flower, herb production, in the process saving a significant quantity of water. In an aquaponics system, effluent that is generated from the fish tanks is pumped and used in fertigation of growth medium beds (GMB) in hydroponic culture. In return, this process is worthy to the fish, because crop plants roots system together with rhizobacteria helps to extract available nutrients from water solution. The nutrients materials produced from fish algae, manure, and decomposing uneaten fish feed are pollutants that could build up to lethal levels in fish tanks, however, this instead waste serve as liquid mineral fertilizer in hydroponic culture. The hydroponic culture function as a biofilter removing off ammonia, nitrates, nitrites, and phosphorus and other trace elements, so the freshly cleansed water can then be recirculated back into the fish tanks. The nitrifying bacteria living in the gravel and in association with the plant roots play a crucial role in nutrient cycling. In the absence of these microorganisms, the whole system would be dysfunctional.
Role of Hydroponics & Aquaponics in Food Security
Food security exists when all people, at all times, have physical and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life. There are four food security pillars which define, defend and measure food security status locally, nationally and internationally. These are food availability, food accessibility, food utilization and food stability.
On top of food and nutrition security agenda/resolution is to achieve a method or programme that can directly support people with the opportunity to realize food security, particularly nutrition security. Developing simplified Hydroponics systems to make nutritious food production achievable for one and all is the core mission of Hydrilla Urban farms.