Download as a PDF - CiteSeerX

In terms of the risk assessment for each field, Table 6 shows that even a 10% reduction
in fertiliser use can have a significant impact on each field. Under the current farming
practice of using the maximum recommended fertiliser rates, 191 fields are classified
as very high risk (Figure 1) but this number is reduced to 16 with a 10% reduction in
fertiliser use (Figure 2) and to 13 fields with a 20% reduction in fertiliser. This also has
a knock-on effect on fields classified as high or medium risk.
Table 6:
Impact of fertiliser reduction to the extent of risk (number of field
plots)
Very low
risk
Low risk
Medium
risk
High risk
Land use 2002 0 922 414 569 191
10% reduction in
fertiliser use
0 922 642 516 16
20% reduction in
fertiliser use
0 922 646 515 13
Very high
risk
However, farmers believe this scenario would affect the grain outputs from arable
production and the number of livestock units per hectare and therefore farm income.
On the other hand, farm expenditure on chemical fertilisers and grain seed would be
less. For example, at 2002 figures, fertiliser costs were £79–£105 ha depending on
the chemical mix required for the range of crops grown.
265