§ 6. Mr. Gareth Wardell
To ask the Minister of Agriculture, Fisheries and Food what was the number of incidents of river pollution caused by nitrates in the last year.
§ Mr. Wardell
In view of the Prime Minister's welcome, albeit recent, conversion to the importance of environmental matters, does the Minister agree that it is not enough to prosecute offenders against the environment? Should not his Department do far more to assist agriculture systems that entail a lower reliance on artificial nitrogenous fertilisers?
§ Mr. Ryder
The hon. Gentleman should be aware that only a small proportion of nitrate pollution comes directly from fertilisers. The Government are acting on that front. Even if nitrate fertilisers were banned today we should still 473 have nitrate pollution in 40 or 50 years' time, because the worst form of such pollution is connected with the ploughing up of old grassland. In the immediate aftermath of the war, in the 1950s, a large amount of grassland was ploughed up for arable use, and that is what has caused a good deal of the present pollution.
§ Mr. Lord
Has my hon. Friend seen the results of the research by the Rothamsted research institute? That research clearly shows that the problems caused by nitrates in water can best be improved through sensible modifications to current farming practice. Will my hon. Friend do his best to encourage farmers to put those alterations into operation, and resist demands for hasty or draconian measures that might do much more harm than good?
§ Mr. Ryder
I have read the Rothamsted report, and the advice that it gives. It is absolutely correct—that nitrogen fertilisers should not be applied in the autumn, that wherever possible the soil should not be left bare during the winter and that winter-sown crops should be sown early in the autumn. If a spring crop is to be sown, a winter catch crop should be grown. That advice should be followed by farmers if the problems to which the hon. Gentleman refers are to be reduced.
§ Mr. Gale
When my hon. Friend is very properly considering nitrate levels, will he take into account the fact that it takes 20 years for nitrates spread on the land to filter through to aquifers? Will he take particular account of the fact that areas such as Thanet have very high natural nitrate levels in the soil, and will he make absolutely certain that the farming community does not carry the can for geological factors not under its control?
Mr. Alan W. Williams
May I seriously challenge the Minister's earlier explanation about nitrates in water? He said that the problem was to do with grassland. Is it not strange that high nitrate levels in water supplies occur in the very areas where fertiliser usage is at its most intense?