Environmental Imperative
The United Nations estimates global population has increased by over 1 billion since 2005 and will near 9.8 billion by 2050 [ref]. The demand that we place on agricultural products has risen in parallel. We rely on the agricultural sector to provide not only food, but also fuels, shelter and fabrics. In turn, the agricultural sector relies on the application of synthetic fertilisers to maintain crop productivity. Nitrogen, phosphate and potassium (NPK) based fertilisers provide crops with essential macronutrients required for growth. NPK consumption is predicted to increase to 201.7 million tonnes by the end of 2020 [ref].
NPK fertilisers significantly increase the yield of staple foods such as maize, wheat and potatoes but they also play a large role in in climate change. Nitrogenous fertilisers are produced using the Haber-Bosch process [ref]. This process is energy intensive, requiring 600kg of natural gas to produce 1000kg of ammonium, and resulting in the release of 670 million tonnes of CO2 per annum [ref].
In addition, fertiliser application has been shown to have a negative long-term impact on soil health [ref]. Synthetic fertilisers cause soil pH to decrease, degrading soil crumbs and resulting in compact soils with reduced water drainage and air circulation; both have negative impacts on plant-root health [ref]. Meanwhile, the accumulation fertiliser run-off leads to eutrophication in water courses. Eutrophication impacts water quality and allows algal blooms to form affecting biodiversity through toxin production and promotion of a hypoxic environment[ref]. This reduces the availability of clean drinking water with additional costs incurred to process water for drinking.
Natural Symbiosis
Not all plant species require the addition of large amounts of nitrogen. Legumes, such as peas, beans, clover and soy, form symbiotic relationships with rhizobial bacteria. These bacteria colonise the roots structures where they biochemical fix nitrogen that becomes available for the plant [ref].
Mycorrhizal fungi form extensive networks with many plant roots enhancing their access to nutrients and water. And both fungal, bacterial and archeal micro-organisms are known to inhabit the plant tissues. These are a natural and wide ranging phenomenon dating back to the Devonian period. The earliest land plants show evidence of fungal endophytes.
Human Practices
Its predicted that for every 1 °C increase in atmospheric temperature, 10% of the land where we grow crops will be lost. [8] There needs to be a paradigm shift in the way we are addressing the issues facing the agricultural industry. Governments and local authorities are responsible for providing and upholding essential services for its citizens, this especially poignant for the provision of food and protection of farmland.
The effects of climate change are becoming more noticeable as time progresses; we are losing staggering amounts of valuable farmland due to mass flooding, freak weather events, soil erosion, infectious diseases and deforestation. Over the next 50 years, farming is going to become even more marginalised [9].
One way of protecting our crops and the land we use for agriculture is by growing within controlled, contained environments. Growing indoors is already a well-established practice; greenhouses are widely used and guarantee a safer, and more established method of growing all year round. There are many benefits of applying the contained, controlled environments found in greenhouses into urban spaces, these include;
- Providing Newcastle with fresh produce all year round.
- Reducing the carbon footprint of crop production due to reduced food millage.
- No agricultural run-off.
- Limited need for pesticides and fertilisers.
- Safer crops as there is less risk of contamination.
- Reduced spoilage because of shorter transportation times and reduced handling.
With developing technologies in the field of sustainable energy, it could one day be possible to engineer contained growth systems that are self-sustaining regarding its energy usage. By carefully controlling the parameters within these environments, we can emulate perfect surroundings that allow the crops to grow to their full potential, maximising yield.
We are attempting to use a system like this in our project. We are taking a global issue and trying to implement it at a local scale. Newcastle City council has recently declared their bold plans to convert Newcastle into a ‘Smart City.’ Looking into the proposed scenarios, we saw an opportunity to propose a ‘sustainable agriculture’ scenario.
We have researched into areas of the city where we feel space is being underutilised, areas in which a sustainable food source would be most effective. After looking into the urban agriculture industry and communicating with stakeholders, we found a space that gives access to locations across the city. Newcastle’s Victoria Tunnel; they are a disused network of tunnels that were once used to transport coal from the river to locations across the city. They run beneath a variety of urban hubs that would benefit from fresh produce including: Newcastle University, Northumbria University, Royal Victoria Hospital, Student villages and Business centres. We have put together a theoretical design project that outlines how we many implement this idea into Newcastle.
Project Description
Our Goals
We believe engineering endophytes is the new paradigm in plant productivity, as a result our goal was to characterise Pseudomonas sp. endophytic properties and optimise transformation protocols. Pseudomonas sp. Could subsequently be engineered to express genes of interest that could change the physiology of the plant.
The goal of our Human Practices work was to generate a conversation locally about the use of Newcastle's Victoria Tunnel as an urban farm. In doing so, we wanted to raise larger questions surrounding the use of GM bacteria to increase plant productivity, as opposed to genetically modifying the plant itself - challenging consumer views on GMOs.
Alongside this, our goal was to build a hardware prototype for the Victoria Tunnel; and address the lack of suitable hardware that would allow us to grow large numbers of plant seedlings in a controlled environment for the purposes of our project. The hardware needed to be cheap, energy and cost efficient, and a standardised method for growing plants.
Description
References & Attributions
1. Smith. B (2002). "Nitrogenase Reveals Its Inner Secrets" Science Journal 297: 5587
2. Gómez-Lama Cabanás C, Schilirò E, Valverde-Corredor A, & Mercado-Blanco J (2014) The Biocontrol Endophytic Bacterium Pseudomonas fluorescens PICF7 Induces Systemic Defense Responses in Aerial Tissues Upon Colonization of Olive Roots. Frontiers in Microbiology 5:427.
3. Gross, H. and J. Loper (2009). Genomics of Secondary Metabolite Production by Pseudomonas spp.
4. Sharma SB, Sayyed RZ, Trivedi MH, & Gobi TA (2013) Phosphate Solubilizing Microbes: Sustainable Approach for Managing Phosphorus Deficiency in Agricultural Soils. SpringerPlus 2:587.
5. Ruffner, B., et al. (2013). "Oral Insecticidal Activity of Plant-Associated Pseudomonads." Environmental Microbiology 15(3): 751-763.
6. Jousset, A., et al. (2009). "Predators Promote Defence of Rhizosphere Bacterial Populations by Selective Feeding on Non-Toxic Cheaters." The Isme Journal 3: 666
7. Vanitha SC & Umesha S (2011) Pseudomonas fluorescens mediated systemic resistance in tomato is driven through an elevated synthesis of defense enzymes. Biologia Plantarum 55(2):317-322.
8. Despommier D (2011) The vertical farm: Controlled environment agriculture carried out in tall buildings would create greater food safety and security for large urban populations. J fur Verbraucherschutz und Leb 6(2):233–236.
9. Despommier D (2011) The vertical farm: Controlled environment agriculture carried out in tall buildings would create greater food safety and security for large urban populations. J fur Verbraucherschutz und Leb 6(2):233–236.