Too much fertilizer, too much slurry!

Published on: Last updated:

Temps de lecture : 2 minutes  

98% of the nitrates that flow into our rivers come from agricultural activity: From mineral fertilizer waste and from millions of cubic meters of liquid manure produced by pigs and poultry kept in crowded conditions on industrial farms.

Too many animals

Only 7% of the country’s agricultural land is in Brittany, but the region is home to millions of pigs, 94 million poultry birds and 2.25 million cattle. Each year, these animals produce approximately 227,000 tons of nitrogen. This concentration was worsened by public authorities who for a long time accepted regulation violations, despite the fact that such violations caused considerable environmental damage.

Even though it has been known since 1980 that several cantons in Brittany are saturated with liquid manure and that agricultural land surface insufficient to eliminate it, these cantons were not officially classified as structural surplus areas until 1997. Between 1997 and 2002, the number of these cantons in ZES (Special Economical Areas) increased from 70 to 104! Attempts to limit the expansion of breeding were carried out, especially while C. Lepage and D. Voynet were agriculture ministers. However these efforts were quickly circumvented on the pretext of developing “family” breeding, which accounts for up to 60% of breeding in certain types of farming. Since summer 2005, in the interest of “letting Breton breeding breathe”, restrictions on industrial farm expansion in ZESs have disappeared: farmers can now replace cows or chickens with pigs, and concentrate their entire production on a single site – a situation that is confusing to say the least.

Developed in 1997 and expected to produce results by 2006, surplus absorption programs (underestimated according to scientists at the Rennes office of the National Institute for Agricultural Research (INRA)) only helped eliminate 40% of the region’s excess nitrogen.

Worse still, the sometimes virtual character of poultry manure “transfers” is not taken into account: 20% of the time, manure that should have been exported out of Brittany is found in neighboring cantons or departments.

Too much fertilizer

For years, the people in charge of agriculture claimed that liquid and solid manure would replace the use of mineral fertilizers. But reality is not that pretty: Companies still partially compensate fertilizer suppliers according to the amount that is commercialized. Milk and beef cattle producers, who have access to manuring areas, are not always interested in absorbing the liquid manure surplus of neighbors with off-land pig or chicken production sites. For them, the use of chemical fertilizers is inexpensive, dependable and convenient.

As a result, the cut in the consumption of nitrogenous fertilizers fixed at 30,000 tons by the Action plan for sustainable development of agriculture and food processing, only applied to 12,000 tons.

The much heralded “Prescribers Charter”, signed in 2001 and financed by substantial public funds, was meant precisely to mobilize fertilizer suppliers and distributors to reduce waste. A 2004 assessment of this charter requested by the financing parties (such as the water agency, Regional Council and government) revealed the approach was “not very effective”.

Trop d’engrais, trop de lisier !, November 2007

Water and rivers of Brittany

Media Query: