Compared with meat and fish, potatoes and cereal products (pasta, bread and grains) have a low environmental impact. Rice that is grown in flooded paddies releases a relatively large amount of greenhouse gases and therefore affects the climate more than cereals and potatoes.
Potatoes, cereal products and rice that have been produced with little or no pesticides, such as organic alternatives, contribute to a non-toxic environment.
Effect on the climate
For potatoes, cereals and rice, the emission of greenhouse gases comes mainly from cultivation and transportation. During cultivation, it is the use of fertiliser – particularly mineral fertiliser – and ploughing that releases greenhouse gases. Flooded rice paddies result in considerably higher emissions than cereal and potato cultivation, since methane gas is released from the wet ground. Some rice farmers dry out the paddies during certain periods to reduce the release of greenhouse gases.
If we compare the portionsize, the difference between rice and potatoes is not so great. This is because potatoes do not change in weight during cooking, whilst rice more than doubles in weight. The difference between rice and cereal products also decreases when we consider the energy needed for processing pasta, couscous, bread and so forth. In spite of this, a portion of rice has a greater impact on the climate than a portion of potatoes or pasta.
Since the cultivation of cereals and potatoes causes comparatively small emissions of greenhouse gases, emissions from transportation have a proportionately large impact. How great an impact it has depends on how far, how efficiently and by what transport method the product is shipped. Transportation by train and boat results in lower emissions than long distances by truck.
The use of pesticides
Generally speaking, greater quantities of pesticides are used when growing rice than potatoes. The smallest quantities of pesticides are used in the cultivation of cereals.
The environmental impact of pesticides depends on the quantity used, how these are handled and the type of agent, which, in turn, depends on the cultivation technique and climate factors. In countries with a colder climate, the problem of pests and diseases is often less significant, so that, in general, smaller quantities of pesticides are used than in warmer countries.
Chemical pesticides are not used in organic production, which reduces the environmental impact from toxic substances. However, organic production, particularly potato farming, can involve problems, because some of the crop is in danger of being ruined because of pests or diseases. This means that wastage in some years can be considerably greater than for conventional potato crops.
This information has been compiled in cooperation with the Swedish Environmental Protection Agency.