Preface

Global warming, the extinction of species, and the massive deterioration of planet Earth interconnect into an important and urgent problem: the ecological crisis. If it doesn't affect 7.6 billion humans already, it will for sure affect more than 8 billion sooner than we think.

Talking about it has raised awareness, but it is only action that will prevent these issues from becoming the catastrophe of our times. At The Knowledge Society we know, and firmly believe that to solve the world's biggest problems, we need to understand root causes, and leverage exponential technologies to tackle them accurately, aggressively, and quickly.

Synthetic biology has demonstrated to be a multidisciplinary field, a sustainable approach, and a united community through which we can create innovative solutions. From our perspective, synbio means designing, engineering, and growing with and for the most advanced technology known to human kind: nature itself.

We are TKS_International, 10 teens from around the world participating for the first time in the international Genetically Engineered Machine competition in its 2021 edition with one mission: addressing the root cause of eutrophication through synbio.

The problem

Chemical fertilizers

These are substances which mainly contain phosphates, nitrates, ammonium and potassium salts that are applied to plants to enhance their growth. They're also a source of heavy metals like Hg, Cd, As, Pb, Cu, Ni, and Cu.

Advantages of this type of fertilizer include being immediately available to the plants, such that the effect is usually direct and fast, and having enough nutrient content so only relatively small amounts are required for crop growth, also increasing the cost advantage per crop for farmers.

For instance, maize is the most produced crop worldwide (822,712,527 tons yearly) and the most fertilizer-hungry one, consuming approximately 9 tons/ha.

Unfortunately, the great drawback is the environmental impact these products have. Soil, water, and air pollution, in addition to eutrophication, are only some examples of the negative consequences of the use of chemical fertilizers.

Fertilizers with high levels of sodium and potassium can eventually change the soil's pH and promote the accumulation of toxic chemicals which can then expand to the food chain.

Nitrate is the most common nitrogen contaminant as it dissolved in water easily, potentially polluting drinking water and rivers. It has been estimated that in ideal conditions, about 2-10% of the fertilizers interfere with the surface and ground water.

Arid and semi-arid areas are specially vulnerable given their high evaporation rate. Chemical fertilizers can be transformed into other dangerous compounds like carbon dioxide, methane, hydrogen sulfide (H2S) with chloro-fluoro hydrocarbons, such as halon gases.

Eutrophication

Our parents always tell us to eat fruits and veggies because they contain useful nutrients for our bodies. They've also told us though, that everything in excess is bad, and that is precisely the case for water bodies.

Eutrophication occurs when too many nutrients, mainly nitrogen (N) and phosphorus (P), are added to bodies of water and cause excessive growth of algae. This is a serious problem, since it can ultimately lead to the whole depletion of these environments, but just before going too far, let's look at the root cause of the problem.

Chemical fertilizers currently used to nourish plants and increase crop yields are unsustainable in many different ways. First of all, their manufacturing process produces Green House Gases (GHGs), contributing to 3% of worldwide emissions. They pollute underground and surface water, and require non-renewable resources. Additionally, their use actually reduces soil fertility in the long term, plants can only take up about 50% of the fertilizer they're applied, AND they pollute water bodies when they run off. Then using them doesn't make sense!

But how though? Well, when nitrogen and phosphorus aren't fully utilized by plants, they can be lost from the farm fields (runoff) and start polluting adjacent water bodies. That's when eutrophication starts.