Long-term effect of fertilization on grassland coenoses
1991
Lihan, E. | Jezikova, O. (Vyskumny Ustav Luk a Pasienkov, Banska Bystrica (SR))
Trials with N application rates from 50 to 200 kg per ha and with NPK ratios (1:0,3:0,8 and 1:0,15:0,4) were conducted for 28 years at three sites, representing climatic conditions of Central Slovakia and main types of grassland (alluvial meadows in warmer regions, rainfed grassland in the mountains) with following conclusions: Species composition varies with the ecological conditions and with the local proportions of agrobotanical groups and species in the stand. Agrobotanical groups change their proportions to a great extent, so there is some cyclical pattern of development, especially in clovers. The variability of rainfall during the growing season in the alluvial sites is lower than the variability of the yields, so the yields do not depend so much on rainfall. The reverse is true for mountain grasslands. Increased application rates of phosphorus and potassium slightly contributed to the production increase. A greater differentiation was recorded in the concentration of minerals (P, K, Ca) ratio. This suggests that it will be possible to control these ratios to adjust them for the different categories of livestock.
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