An altered microclimate after harvesting may affect the soil nutrient content. There is a growing concern about clear cuttings. Shelterwood cuttings are an alternative practice to clear-cutting. Compared with clear-cutting, shelterwood cuttings cause fewer changes in the soil microclimate and in the physical, chemical and biological soil properties. Shelterwood harvesting may mitigate the impact of harvesting on the ecosystem’s functioning. The aim of the study was to evaluate the effect of shelterwood and clear-cuttings on forest soil chemical properties relative to uncut sites, and to determine their changes after shelterwood cutting in pine-dominated stands on sandy soils of the European hemiboreal zone, in Lithuania. Nitrate and ammonium nitrogen in mineral soil was estimated in shelterwood, clear cuttings and in a mature stand. Changes in organic carbon, total nitrogen, nitrate and ammonium nitrogen, available phosphorus and potassium in mineral soil were estimated in 1-, 3-, 5- and 7-year-old shelterwood cuttings as well. Organic carbon in the soil’s mineral layer in 1- to 7-year-old cuttings sites was higher than in uncut stands. Both organic carbon and total nitrogen were slightly higher in 1- to 5-year-old cuttings. Nitrate nitrogen was higher after tree cutting. The highest mineral nitrogen concentration was in clear cuttings. Changes in the concentration of available phosphorus were similar as in mineral nitrogen. The concentration of available potassium was higher only one year after cutting compared to the untouched stands. Results confirm that shelterwood cuttings had a weaker negative effect on soil nutrients, especially on mineral nitrogen, compared to clear cuttings. The effect of shelterwood cuttings on soil nutrient was short-lived and lasted up to 5 years.

23.1.2018