Premium
Long‐term effects on sward composition and animal performance of reducing fertilizer inputs to upland permanent pasture
Author(s) -
Yu Y.W.,
Fraser M. D.,
Evans J. G.
Publication year - 2011
Publication title -
grass and forage science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.716
H-Index - 56
eISSN - 1365-2494
pISSN - 0142-5242
DOI - 10.1111/j.1365-2494.2010.00772.x
Subject(s) - pasture , lime , agronomy , fertilizer , nutrient , stocking , litter , zoology , productivity , environmental science , biology , ecology , paleontology , macroeconomics , economics
This study investigated the long‐term effects on sward composition and animal performance of applying different fertilizer regimes to upland permanent pasture. The experiment, which was carried out in 2008, was based on a set of replicated ( n = 3) plots that had been established in 1990. The effects of applying (i) N, P, K and lime, (ii) P and K plus lime and (iii) lime only were compared with a treatment that received no nutrient applications. Using a put‐and‐take stocking system, the plots were grazed to a target sward surface height of 4 cm by ewes and lambs from April to early August and by ewes only from August to mid‐October. The long‐term reduction in nutrient inputs had led to decreases in the percentages of both sown and unsown grass species within the sward ( P < 0·05), and an increase in the percentage of mosses and litter ( P < 0·05), with a corresponding reduction in nutritional value. Although there were no statistically significant treatment‐related differences in lamb growth rates, lower fertilizer inputs were associated with a marked decline in stock carrying capacity and associated overall productivity during both the pre‐ and post‐weaning periods ( P < 0·001). The findings highlight the challenges faced when attempting to reconcile production and environmental objectives in upland systems.