After selective wood tree harvesting, organic matter accumulation and nutrient availability in forest soils are usually negatively influenced, especially during the first years. The hypothesis that 15 years after selective wood tree harvesting (15Y) the increased forest biomass, together with the enhanced nutrient recycling rates ‒ compared to 5-year wood tree harvesting (5Y) ‒ could restore nutrient availability and organic C accumulation (both in forest floor and soil) to similar levels to the intact site, was tested. The aim of this study was to investigate the effect of the timing of management practices (intact forest-control, 5Y, 15Y) on organic matter content, nutrient concentrations in needles, forest floor and soil, in a forest ecosystem of Picea abies L. In each of the three treatments, 5 sites (plots) were included for soil sampling, while in each site one soil profile was included for sampling. In addition, the depth of the organic layer was measured per site. Finally, in each of the 5 selected plots per treatment, 10 composite samples of green needles of Picea abies were randomly selected, in order to determine the nutrient status of Picea abies plantations. Significant differences among the control site and the 5Y and 15Y treatments were found for soil N, P, C/N, exchangeable Ca, organic matter and nutrient accumulation (basically in the upper 30 cm). Similarly, significant differences among the intact forest and the other two treatments were recorded in foliar K, Fe and Zn concentrations. In conclusion: i) forest management practices clearly influenced soil fertility and organic matter accumulation, ii) 15 years after selective harvesting nutrient and organic C accumulation in forest floor, as well as K and Fe accumulation in soil, were restored to similar levels to the intact sites; thus, our hypothesis was partially correct.

 

 

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This abstract was accepted to be presented at the conference entitled “40 Years of Horticulture Education in Cluj-Napoca†Cluj-Napoca, September 27, 2017, being included in ‘Book of Abstracts’ of this special-anniversary event (http://conference.shst.ro). All accepted papers will be published in a special issue of Notulae Botanicae Horti Agrobotanici Cluj-Napoca journal.