The agricultural revolution has granted the sector electric tools for what used manual or animal labour. Throughout time we have brought down bushes separating crops to make space for large plots of land that a tractor can plough. We have heightened our use of fertilisers and pesticides changing the productivity of our crops and land area. In developed countries where land is scarce and populations’ consumption is high, we are left with the choice to increase the productivity of the same area to feed our growing and wasteful population. So through all these changes has agriculture focused on being more productive?
We have failed to promote soil quality and regenerative agriculture making our system hooked onto fertilisers.
How much does it cost in the UK?
- Soil degradation -> £1.2bn per year (calculated in 2010)
- 4 million hectares of soil are at risk of compaction in England and Wales (out of 15 hectares including 9.5 used for agriculture)
- Soil compaction increases risk of flooding (cost of flooding £1.6 bn)
- 2 million hectares of soil are at risk of erosion in England and Wales
- Soil in the UK stores the equivalent of 80 years of emissions but cultivating it has made it loose 40 to 60% of the carbon
What issues are in the soil?
The soil in developed countries is depleted of its nutrients due to intensive agriculture. For instance, soil compaction due to cattle meaning leads to soil erosion. This has several consequences: reduced water infiltration, lower nutrient absorption. The soil is depleted of nutrients due to mono-culture, large fields and less biodiversity allowed on the fields.
Soil erosion impacts the water and soil quality leading to greenhouse gas emissions. Usually, soil is a carbon sink so reversing its ability to absorb carbon into emitting carbon has a large impact on GHG reduction (WWF, 2006). Soil erosion can have eutrophication as an impact too (algae reproduction on the surface of the water leading to dead zones where the ecosystem collapses)
What roles do fertilisers have?
Fertilisers have enabled higher yield while pesticides have pushed away fungi, vertebrates and invertebrates that ruined crops and reduced production. But often when humans take over nature, nature knows how to fight back. Fertilisers have changed the chemical balance of the soil leading to several issues such as a change in pH or a topsoil too rich in nitrogen. Unfortunately, fertilisers do not just stay in the soil. They are not absorbed entirely leading to runoffs changing also the ecosystem in waterways. These runoffs are made worse by poorer soil quality. The vicious cycle of using fertilisers encourages farmers to use more fertiliser when the soil’s quality is poor worsening soil quality etc
What are the solutions?
In order to respond to growing demand, one can increase productivity or the size of the land used for agriculture. Productivity has been improved by using fertilisers among other things and mechanical techniques requiring mono-culture and large fields. Fertilisers’ impacts are so far reaching that it seems this solution should be kept for very particular occasions (certain crops, poor weather …) but has been overused.
We can use tested and trusted methods to enable the soil to regenerate or put our trust in technology and innovation. The first option would encourage growing winter cover crops to avoid the soil being damaged and offer soil further nutrients to be captured. Similarly growing legumes ensure storing nitrogen deep in the soil for future crops to use. Permaculture and regenerative agriculture are interesting pathways. Large investment in research and development would be necessary to reverse the damage done quickly. Agro-industries invest very little in research and development. This may be due to a lack of regulation or constraints. No matter the reason it has a ripple effect on farmers who cannot use novel ideas until they have been brought to market.
The government has a role to play to ensure that the future of the soil is not compromised by the current doings of the farming industry. Changes are unlikely to be industry-led given the current enjoyment of the last fertile parcels of land
Unwrapping the Supply Chain 