Variaciones de la vegetación en prados sometidos a siega y abonado en la montaña de León

Abstract

The aim of the present study was to investigate the influence of the application of N, P orK fertilizers on floristic composition of the herbage harvested from different paddocks of a mountainmeadow located in the Mountain of León (Cantabrian Mountains, Spain). For ten years each plot was harvested twice a year (June and September) according to a traditional harvestsystem. Some species richness parameters as well as floristic composition was maintained (fortybotanical species) but the proportion of total biomass of each species was affected by fertilization.Eighty percent of total dry matter forage yield is obtained from a reduced number of speciesthat are considered the group of ‘the most productive species’. D. glomerata, H. lanatus, F.pratensis, L. perenne and P. lanceolata were always part of this the most productive species groupin all the fertilizer treatments. Fertilization affected the production of different botanical species.N fertilization increased A. elatius yield but decreased C. cristatus, P. trivialis, T. pratense andP.lanceolata yield. Application of P fertilizer increased A. elatius, P. pratensis and T. repens productionwhereas decreased T. pratense and P. lanceolata production. K fertilization increased T.repens and reduced D. glomerata, P. trivialis and T. oficinale. All the fertilizers decreased the proportionof C. nigra and C. capillaris. Fertilization also affected the main botanical groups yield,grouped according their agronomic quality. N fertilization increased the proportion of the best qualitygrasses (G1), whereas that K increased the group of the worse quality grasses (G3). N fertilizationnegatively affected the proportion of legume, and both N and P decreased the proportionof the group of other dicotyledoneus herbs of agronomic interest (O1).