P loss from farming is not only environmentally damaging but a financial cost to the farming industry.

The sources of P loss from farming include organic manures, fertilisers, surface run-off, drainage, dirty water and soil erosion. Research has shown the largest contributor to P loss is surface run-off of P in the first rainfall events after the application of fertilisers. It is important to note that P does not leach from the soil, rather it is physically transported in surface run-off.

There are huge differences in the amount of P run-off generated by different types of fertiliser as demonstrated in the graph below.

The above figures summarise data from trial work conducted by the National Institute of Water and Atmosphere (NIWA), New Zealand in which they compared the surface run-off losses of P arising from water soluble TSP and Gafsa RPR.

The results show:

1. In the first rainfall event after the application of fertiliser, the quantity of P in the run-off from the TSP plots was 170 times higher at 5585 mg / l compared to Gafsa RPR which was negligible at 33 mg /

2. The P loss in run-off from Gafsa RPR was very similar throughout the duration of the 232 day trial to that of the zero P control plots and, could not therefore, be said to have caused any appreciable increase in the loss of P.

3. Conversely, the loss of P from the TSP plots in the first two rainfall events after fertiliser application (at 3 and 10 days) was, by comparison, massive and did contribute significantly to P loss to water courses.

4. After one month the level of P loss from TSP had subsided (it did continue at a higher level than the control and Gafsa RPR) but, by this point, the damage to the environment is done.

SUMMARY

The SAC trial and the NIWA trial from New Zealand demonstrate the agronomic and environmental effectiveness of Gafsa RPR respectively. These trials, together with experience and practice gleaned from the UK and New Zealand, has enabled Carrs Fertilisers to take an increasingly scientific approach to the development of its Scotphos range of products and the associated technical advice and services.

Carrs Fertilisers have also been able to utilise this scientific validation in the development of other product ranges, most notably New Choice

With farmers under ever increasing economic and environmental pressures it is vital they use fertilisers which offer genuine agronomic benefits, protect the environment and are cost effective.

The Scotphos range can meet all three of these important criteria.

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