The competitive ability of Viola arvensis Murr., and its responses to grazing and fertilization in Tylldalen, Nord-Oesterdalen, Norway

abandoned land achillea benomilo benomyl conduite des herbages conservation du paysage control methods dactylis glomerata fertilisation fertilizer application grassland management grasslands grazing herbage highlands land diversion land productivity land use landscape conservation manejo de praderas mycorrhizae noruega norway pastoreo plant animal relations plant response praderas productividad de la tierra relaciones planta animal relation plante animal respuesta de la planta retrait des terres tierras abandonadas utilisation des terres vicia cracca viola