Organisation - June 13, 2013

Ammonia measurement methods are OK

No doubts about measure­ments of ammonia emissions.
But method is described as 'dated'.

The methods for measuring ammonia emissions in the Netherlands, developed in part by Wageningen UR, are scientifically correct, concludes state secretary for Economic Affairs Dijksma in a letter to Parliament on the basis of an international review. Early this year, there were criticisms of the Wageningen method after a thesis by one of agronomist Egbert Lantinga's students was leaked to the farming press. Her ammonia measurements raised doubts as to whether the Wageningen method correctly calculates the effect of surface spreading of manure on ammonia emissions.
The British scientist Mark Sutton of the Centre for Ecology & Hydrology in Edinburgh has now given a definite answer. The integrated horizontal flux method on which the Dutch emission factors are based is a scientifically solid basis for determining the ammonia emissions from manure, concludes Sutton. In contrast, the tunnel method used by Lantinga is not a good measure. Besides Sutton, two experts from France and Denmark reached the same conclusion.
Sutton does make the comment that the Wageningen method is rather dated. 'The Netherlands used to be a world leader in the estimation of ammonia emissions, but the scientific supporting data is from the 1980s and 1990s.' The Dutch contribution in this field has stagnated since then as the government has been investing less money in ammonia research, notes Sutton. State secretary Dijksma has responded to Sutton's signal. In her letter to Parliament, she says she aims to make funds available for new field measure­ments using the latest scientific measurement methods.