Impact of fertilisation and liming on botanical composition and yield in a mountain pasture.

Abstract

Among the main utilization’s categories of agricultural land, in Romania can be mentioned: arable land, which represents approximately 63,9%, pastures which represent 22,8% and hay lands which represent 10,2% (Statistical Yearbook, 2006). In Romania Festuca rubra natural pastures occupy an area about 1 million ha (Marusca, 2001). The experiment was settled down on a F. rubra pasture (R 3803 habitat; Nature 2000-6510) in Cindrel Mountains at a 1348 m altitude on a Districambosol type of soil, characterized by acid pH and a low level of P and K supply. The research started in 1998 and was continued till 2006. The experiment was organized in randomized blocks with four replicates and included the following treatments: 1) F. rubra – Agrostis capillaris natural pasture as control; 2) 100/22/83 kg N/P/K ha y; 3) sheep folding during 3 nights (one sheep m); 4) 0/22/83 kg N/P/K ha y + over sowing with Trifolium repens (in 1998); 5) 0/22/83 kg N/P/K ha y. The variants were combined without liming (V1-V5) and with liming (V1’-V5’, one receiving 5.5 t haCaCO3). The grasses were dominant during 1998-2002 in absence of liming. Festuca rubra occupied the first place in the sward of all treatments. In 2002, average soil content in mobile P and K determined in V2’ an increase of A. capillaris ratio (65%), a species more valuable than F. rubra, which became dominant. As well, an average content of soil in P and K determined in V4’ an increase of legumes ratio (T. repens 75% from sward). In 2006 on without liming soil the most important modification of sward floristic composition was recorded for V2 treatment, which for A. capillaris had a ratio about 75%. An important modification of grasses floristic composition was observed at A. capillaris specie too in case of liming soil (60% in V1’, 90% in V2’ and 55% in V5’). The floristic composition analyze indicates an increase of legumes ratio in the sward of 3’ (with 10%) and 5’ (with 10%) treatments, respectively a very strong decrease of them in V4’ (with 70%) treatment in 2006, in comparison with 2002. Best forage yield was obtained for V2’ treatment, in 2006. Yield efficiencies obtained through the use of chemical fertilizers are significant in comparison with experimental control and the results of each treatment differentiate from the others.