Dr. Aine O'Connell:

Earlier, a statement was made to the effect that we would see improvements in water quality within 12 months. In some areas that is possible, but the research from Teagasc Johnstown suggests that at large catchment scale, it could, depending on a wide variety of factors, take from seconds to days to months to years or to decades. Inferring that there is a direct linear relationship between stocking rate or source load and what is lost out of a catchment is quite irresponsible. There is a lot more going on in the catchment.

Senator Daly asked about the correlation between the 2018 drought and the rise in fertiliser sales. At the EPA conference, we were told that despite the drop in fertiliser sales last year, we did not see a corresponding drop in nitrates. The witnesses at the meeting earlier today failed to mention the impact of mineralisation on soils and nitrate loss. Equally, there is the opposite of denitrification, which also has an impact on nitrogen. There is a lot more at play than is sometimes considered. We need to be cognisant of that. Looking at the trends set out on page 11 of the report, it is stated that they were statistically verified. However, at the meeting of the water working group, we were told that they were raw averages. With a PhD and having done trend analysis, I can say that if they are statistically verified, you need to be able to determine the order of significance between adjacent years. There is no order of significance between the differences set out in the report. Therefore, to the naked eye or the average reader, it could be assumed that no statistical analysis has been undertaken, because no order of significance is outlined.