By John Spink, Head of the Teagasc Crops, Environment and Land Use Programme, Oak Park, Carlow
There has been an upsurge in interest in diet and the relative merits of plant-based versus animal-sourced foods, particularly related to the impact of diet on climate change.
Whilst a hectare of crop land undoubtedly produces much lower greenhouse gas (GHG) emissions than a hectare of intensive livestock grazing land, the pros and cons of either dietary choice is not that simple.
As a country we have a trade deficit of €1 billion in fruit and vegetables, which means that a large proportion of that plant-based diet is imported and often from regions of the world increasingly suffering from water shortages to produce the crops.
Importing products we can grow
Our single biggest fruit import is bananas at 93,000t. Our climate will have to change dramatically to grow them at home, but our second largest fruit import is apples at 62,000t and they grow very well here.
Moving on to vegetables, our biggest import is potatoes at 72,000t and that’s a crop that’s known in many parts of the world as the ‘Irish potato’.
In addition to fruit and veg we also have a trade deficit of €1.1 billion in cereals and other products for animal feed, the source of which may be questionable from a sustainability perspective.
John Spink pictured at the Teagasc National Tillage Conference 2020. Image source: Dylan Vaughan
Sustainable is local and seasonal
Arguably the most sustainable diet is one that is locally produced and seasonal as it minimises fuel use, so we must consider what can be produced locally.
A large proportion of the land in Ireland is unsuitable for cropping, either due to the soil, or the weather and will therefore either remain as grassland, or possibly be converted into forestry as a profitable land use which will also increase carbon sequestration.
Another issue that few consider is the amount of carbon stored in our long-term permanent grasslands, which is estimated to be equivalent to 1.8 billion tonnes of CO2 or 30 years of our total national emissions. Cultivation of these long-term grasslands results in a rapid release of this stored carbon.
Scope to increase crop production
It may seem therefore that there is little scope to increase crop production from its current 290,000ha.
However, a recent analysis of land use by Jesko Zimmermann, Teagasc data technologist, showed that there were over 428,000ha in frequent crop production.
As a country, therefore, we have the potential to significantly increase our production of both horticultural and tillage crops without impinging on our long-term permanent grassland carbon stores.
This is because we have a very benign climate that is rarely too hot or too cold; we are far north which gives long summer days and we have a ready supply of water from our high rainfall.
It is the latter that is increasingly going to give us a competitive advantage for crop production compared to some of the current global centres of production, which are predicted to suffer more frequent droughts as climate change progresses.
If we can seize this opportunity, we could see increased production of grain for high-value markets such as beer and whiskey production, apples for consumption or cider production, a wide range of vegetables and protein crops to replace soya.