Download as a PDF - CiteSeerX

significant number of arable fields adjacent to the water course without any buffers.
Therefore the majority of fields are classified as high or very high risk. With the
implementation of a 50-m buffer, risk is reduced to low. When applied to the whole
of the catchment there is a net reduction of total N losses of 1.86%. However,
implementing such large buffers may not be acceptable to farmers with smaller
farming units as this will remove a greater proportion of their land from economic
production.
The second scenario investigated reducing fertiliser use (by 10% or 20%) on the
existing land use regime. The results found that nutrient losses for the whole of
the catchment were 8.8% and 17.5% respectively. The third scenario examined
the impact of a radical change in land use. Table 5 shows that if all arable land use
was changed to permanent pasture (i.e. only livestock farming is practiced), nutrient
losses are predicted to be 55% less than they would be under the current intensive
arable regime. However, a livestock-dominated farming system is not popular. This
is because cereal production is seen to be more profitable than livestock farming.
But more importantly to the farming community, the recent outbreak of foot and
mouth disease and previous impacts of BSE have shown how vulnerable livestock
can be to contagious or infectious diseases and farmers would be very reluctant to
specialise.
The final scenario is the most radical model, requiring all agricultural land (including
pasture land) to be taken out of production and converted to woodland. Although this
would reduce the current annual nutrient loss from approximately 902 to 111 mg/L,
the economic, social and environmental impacts are extreme. Assuming plantation
woodland takes over, this takes upward of 30 years to mature before felling takes
place and an economic return made, so this would not be economically viable for
the current farming community. In terms of social change, the range of employment
activities in the local area would alter as the specialised skills of forestry workers
and the number of workers required change. In environmental terms, although
nitrate losses would reduce, there would be increased acidification of water courses,
leading to a decline of aquatic biodiversity. Terrestrial biodiversity would also change
as existing wildlife habitats were destroyed.
263