SLINTEC Building Structure 1500x110-04

Urban Farming; A Solution to Feed the Cities

The United Nations (UN) and Food and Agricultural Organization (FAO) predicts the world population would reach 9 Billion by 2040. The questions is; how do we feed all of them. The answer lies in urban farming.

It is predicted that by 2050, the world would need to raise food production by 50% due to this demographic and lifestyle change and the rise of the middle class. Adapting a protein rich diet by the populace with income increase set to put pressure on livestock production for meat. 

Image by stokpic from Pixabay 

The change in livestock farming and production of meat harms the environment by producing greenhouse gas emissions and necessitates the use of additional water and land. Large scale farming to cater to the demand will also put pressure on arable land and the use of fossil fuels and energy demand.

Therefore, it is imperative to have sustainable approached to produce food while conserving soil, water and energy resource as they are becoming scarce.

Rise of middle class has given rise to urbanization. Urban migration of labour has also put additional pressure for resources in cities. 

Around the world, agriculture now uses 70% of all water drawn. 30% of all the energy used on earth is used in food production and supply chain. These ratios have an adverse effect on ecosystems. There is an urgent need to create more efficient use of water and energy throughout the agri-food chain because the world will have a 40% global water deficit by 2030 and a 30% increase in energy demand by 2040. Climate change will also exacerbate this.

Also, the educated masses especially the consumers are demanding greater transparency and traceability of the origin of their food. This is apparent in the urban middle class.

Thus, urban farming could be the solution in feeding the cities.

As mentioned earlier, catering to the growing demand of food with urbanization, farming practices would need to be redesigned and changed. According to the FAO, urban poor consumers spend 60–80% of their income on food, making them very vulnerable to higher food prices. Hence, the ideal solution is to produce vegetables, fruits and other food or raising animals in and around cities. Urban agriculture is now practiced in both developed and developing countries. 

According to FAO, approximately about 1 billion people are engaged in urban agriculture around the world. Most urban agriculture is done in small plots of land and urban spaces available for cultivation, bee keeping and animal husbandry. Roof top vegetable and fruit gardens are a popular choice in urban agricultural practices. 

Types of urban farming/agriculture

Photo by Vincent Erhart on Unsplash

Permaculture is a type of farming that mimics how nature functions to produce fruit and vegetables on a small amount of land (without pesticides, synthetic fertilizers or mechanically tilling etc.).

Bio-intensive micro-market gardening is the practice of growing organic vegetables on a tiny piece of land to mimic the processes seen in nature.

Photo by Akshay Chauhan on Unsplash

Aquaponics is a type of farming where plants and fish are combined to mimic an environment in an aquarium. The fishes’ activity enables plants to grow naturally with biological filtering carried out by micro-organisms transforms the ammonia contained in fish urine, and fertilises the plants.

Photo by Artelle Creative on Unsplash

Hydroponic System is a system of growing crops without soil, frequently called soilless farming. In the hydroponic system, the plant roots grow in a liquid nutrient solution or inside moist inert materials. The liquid nutrient solution is a mixture of essential plant nutrients in water. 

Image by BrightAgrotech from Pixabay

Vertical farming is the agricultural process in which crops are grown on top of each other, rather than in traditional, horizontal rows. Growing vertically allows for conservation in space, resulting in a higher crop yield per square foot of land used. Mostly hydroponic systems are used.

Benefits of Urban Farming

Urban farming has several benefits as it enables feeding the city with fresh produce, carbon capture and air purification and helps in heat reduction. The concept also enriches the city’s bio diversity and enhances value of empty spaces. 

There are many advantages in urban farming. There are ample examples of this in cities such as New York, Chicago, Paris, Seoul, London etc… Sustainability, better health, and the eradication of poverty are benefits cities can reap.

Both wastewater and organic solid waste can be converted into resources for farming; can be utilized as fertilizer and as irrigation.

Vacant urban spaces can be better utilized for agriculture production.

It is possible to protect other natural resources. Water management is enhanced and there is more fresh water available for household and drinking needs when wastewater is used for irrigation.

Urban farming reduces energy and fossil fuel use (e.g. energy consumed in transporting food from rural to urban areas).

By enhancing the environment through reducing pollution, increasing biodiversity and trapping heat, urban agriculture also makes cities healthier places to live.

Urban agriculture is an effective way to fight hunger and malnutrition as it facilitates access to food by an impoverished sector of the urban population. 

A way forward for Sri Lanka’s impending food crisis

Sri Lankan government throughout the years provided farmers with subsidized chemical fertilizers, irrigation and extension services. Through these policies, yields for staple crops rose as compared to traditional farming techniques. Sri Lankan agriculture was thus dependent on agrochemicals. With the policy decision of the government to ban agrochemicals and ban imports in early 2021, crop yields fell drastically even though the government promoted organic agriculture as a solution. This has resulted in an impending food crisis. Even though the policies were changed and the agrochemical ban was lifted, the prices of chemical fertilizers have gone up in the world market due to various factors including the Russia-Ukraine conflict. Russia and Ukraine are major producers of chemical fertilizer due to their existing petrochemical industries. Coupled with a foreign exchange shortage in the country hampering import of agrochemicals, Sri Lanka’s agricultural output and food security looks grim. Sri Lanka’s most vulnerable populace especially the urban poor and children face the risk of malnutrition and starvation.

Given the impending energy shortage, climate crisis, and conventional agriculture’s reliance on fossil fuels, switching to more sustainable land management systems might be inevitable. Hence urban farming could be a way out. For enhancing urban farming, application of science and technology will be crucial.

SLINTEC’s offerings

Sri Lanka Institute of Nanotechnology (SLINTEC) is a pioneer in nano and advanced research & technology in Sri Lanka. We have focused our resources to create technologies that will solve many pressing problems in emerging nations such as Sri Lanka.

SLINTEC is conducting research on methods to improve soil fertility using plant amendments incorporated with nanomaterials or nano-clays and is in the midst of developing advanced coatings to combat the effect of modern fertilizers. 

The urban farming techniques can be enhanced by the application of science and technology. Fertilizers for food crops can be used via recycling organic waste and production of organic fertilizers as an alternative to all chemical fertilizers. Municipal waste and waste water could be re used for urban farms and community gardens whilst conserving nutrients such as Nitrogen, Phosphorous and Potassium which are essential for plant growth.

In developing countries, the cost of fertilizers can be significant and is often the limiting factor for food supply. Thus, it is important to develop technologies that minimize the cost of fertilizers through efficient and targeted delivery. SLINTEC has reduced the high solubility of urea molecules by incorporating it into a matrix of hydroxyapatite nanoparticles. This solution can be used in all forms of agriculture including urban farming.

“Biochar attached microbial communities” is a new bio-fertilizer formulation that is being developed by SLINTEC that can be used in fixing atmospheric nitrogen and to solubilize mineral phosphate.

SLINTEC has introduced a novel strategy to prepare self dispersing nanosulfur products with efficient fungicidal effects at low dose rates — a self dispersing nanosulfur solution based on polysulfide concentrate. Product can be diluted in solutions with or without adjuvants to form solutions that can be directly applied on target crops.

Bio-pesticides and bio-fungicides developed using microbes provides longer environmental persistence of active ingredient ensures product efficacy for a longer period. Facilitates prolong protection from environmental stress.

SLINTEC is in the middle of developing an advanced seed coatings. The seed coatings have the ability to significantly improve the crop yield. 

Sri Lanka does have a food crisis, but there is also an opportunity. Urban farming and science and technology will be key in unlocking this opportunity.

Author- Ravinda Soysa , Graphics – Lahiru Ranathunga

Graphic/Image Sources-