Effects of two fertiliser treatments on soil characteristics were measured during 1972#x2013;87, within 10 grazed permanent#x2010;pasture #x201C;farmlets#x201D;, on steep hill country in southern Hawke's Bay, New Zealand. The low fertiliser (LF) treatment received 125 kg ha#x2010;1superphosphate p.a., and the high fertiliser (HF) an average 625 kg ha#x2010;1p.a. for 5 years then 375 kg ha#x2010;1p.a. subsequently. Ground limestone was applied to HF in 1975 and 1979. Grazing pressure was the same across treatments. Soil fertility decreased with increasing slope of measurement site, and aspect had a less marked effect. Phosphorus initially accumulated mainly in inorganic forms, with organic P accumulating at a slower rate similar to that for organic S. Olsen P status reflected P application regime, although the responsiveness was lower than anticipated. Soil pH in the non#x2010;limed LF treatment increased slightly over time, probably as a consequence of the decline in soil organic C. Soil total N (0#x2013;75 mm depth) remained constant in LF, but increased by 19 kg ha#x2010;1yr#x2010;1in HF soils. Soil carbon decreased in LF and HF by 200 kg C ha#x2010;1yr#x2010;1This suggests that soil organic matter may be decreasing in some New Zealand pastoral environments.
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