Agricultural nitrogen surplus higher after summer drought of 2022

The nitrogen surplus is the part of nitrogen that is not utilised in agriculture. The nitrogen surplus is calculated by subtracting the amount of nitrogen input (including in the form of concentrates and fertilisers from the amount of nitrogen fixed in animal (meat, milk, eggs) and plant products (arable crops and horticultural crops), and the nitrogen removed outside agriculture (exports, manure processing, private use). A high nitrogen surplus is harmful to the environment as it causes, among other effects, eutrophication and acidification of soil and surface water.

Summer drought caused increase in nitrogen

Since very little rain fell in the summer of 2022, silage and pasture grass yields were lower than normal. Nitrogen fixation in grass was therefore reduced. As a result, only 229 million kg nitrogen was removed from farmland through harvesting for livestock roughage. However, livestock farmers needed 257 million kg nitrogen in roughage for their herds. The deficit had to be compensated by adding roughage from the feed inventory, to a rounded amount of 27 million kg nitrogen. In practice, this meant that much more roughage was obtained from bales and pits than was added to the inventory in 2022. On the other hand, 2021 was a relatively good year for roughage production, adding 10 million kg nitrogen to the feed inventory.

Use of artificial fertilisers declining

In 2022, the two major sources of nitrogen in agriculture were concentrates (410 million kg) and artificial fertilisers (194 million kg). Relative to 2021, input of nitrogen through concentrates fell by 2 million kg, while input through artificial fertilisers fell by 18 million kg. The latter decrease was likely due to higher prices of artificial fertilisers in 2022. These were related to higher natural gas prices.

Livestock excreting less nitrogen

The application of nitrogen from livestock manure decreased from 471 million kg in 2021 to 467 million kg in 2022. Cattle emitted 1.3 percent less nitrogen than in the previous year. This was partly due to the composition of the roughage. In the pig sector, nitrogen excretion dropped by 0.3 percent, and by 0.8 percent in the poultry sector. This was due to the decline in pig and poultry herds. These animals do not eat roughage, instead they only eat concentrates.