Timo Penttilä

Jatkolannoitus Lapin viljavilla rämeillä

Penttilä T. Jatkolannoitus Lapin viljavilla rämeillä.

Tiivistelmä

The paper deals with the effects of refertilization on the growth response of pine growing on drained nitrogen-rich swamps in northern Finland. The results of five replicated factorial experiments are presented. Primary fertilization, mainly with PK, was carried out 10—13 years before refertilization with the following treatments: N, P, K and in three experiments also a micronutrient mixture (H). Growth responses were measured 4—6 years after refertilization. Of the single factors, N had a positive effect in a shallow-peated experiment and the micronutrient mixture in a deep-peated one. The effect of P and K was not significant in any of the experiments. However, the treatment means showed a clear positive effect with NK or NKH, except in the northernmost experiment. The effect of PK strengthened towards the end of the study period. The results imply that primary fer-tilization, especially with P, still had an effect at the time of refertilization. Final conclusions concerning PK fertilization and also the effect of nitrogen should be based on a longer period of observation.

Vastaanotettu 31.10.2017 Julkaistu 1.1.1984

Katselukerrat 1118

Saatavilla http://suo.fi/article/9592 | Lataa PDF