Author(s):
Fernandez-Nunez, E.
; Rigueiro-Rodriguez, A.
; Mosquera-Losada, R.
Date: 2014
Persistent ID: http://hdl.handle.net/10400.5/7250
Origin: Repositório da UTL
Subject(s): pasture; silvopastoral systems
Description
Poster In silvopastoral systems grazing animals coexist with tree production. In these systems there is a great competition between tree and herbaceous plants for light, water and soil nutrients, which affect herbage forage production and quality. The aim of this study was to evaluate the herbage forage production and quality (protein, calcium and phosphorus levels) under Pinus radiata D. Don (pine) and Betula pubescens Ehrh (downy birch) silvopastoral systems after fourteen years of establishment in Galicia (Spain). In spring 1995, pine and downy birch silvopastoral systems were established. Trees were planted at 833 tree ha-1 and a mixture of Dactylis glomerata L., Trifolium repens L. and Trifolium pratense L was sown. Mineral fertilization (N:P:K) was applied every year and was compared to control treatment (no fertilization). During 2009 and 2010, three herbage forage harvests were performed per year in May (spring), July (summer) and December (winter) under downy birch and two harvests (summer and winter) under pine silvopastoral systems. Herbage forage production was estimated and crude protein (CP), calcium (Ca) and phosphorus (P) levels were analysed. The results showed that mineral fertilization significantly increased herbage production under pine and downy birch compared with no fertilization. These increments were about 80% under birch and 90% under pine systems allowing maintaining livestock use after fourteen years of establishment. Mineral fertilization treatment significantly increased CP, Ca and P levels compared to no fertilization. Downy birch systems showed higher Ca and P levels than pine independently of fertilization treatment and harvest. All pine and downy birch silvopastoral systems contained Ca and P above of the recommended levels for cattle and small ruminants maintenance requirements while, CP content was insufficient after fourteen years of establishment.