PubAg

Main content area

Amount of boron in Norway spruce stands in eastern Finland

Author:
Tamminen, Pekka, Saarsalmi, Anna, Kukkola, Mikko
Source:
Forest ecology and management 2012 v.269 pp. 92-98
ISSN:
0378-1127
Subject:
Picea abies, boron, boron fertilizers, ecosystems, harvesting, mineral soils, nitrogen, stems, trees, Finland
Abstract:
The aim of this study was to determine the amount of boron in three Norway spruce (Picea abies (L.) Karst) stands in eastern Finland, where boron deficiency is common. A further aim was to estimate the effects of logging-residue harvest on boron balance and the boron-to-nitrogen ratio on these sites. The data were obtained from a 30-year-old and a 62-year-old healthy spruce stand as well as from a 35-year-old spruce stand with boron deficiency and growth disorders. Altogether 2.1 and 2.4kgha⁻¹ boron, respectively, were bound in trees+organic layer+0–10cm mineral soil layer in the two healthy stands, and 0.9kgha⁻¹ in the boron deficient stand. For the amount of boron in the healthy stands the trees made up 43% and 49%, respectively, and in the boron deficient stand 38%. Stems contained 30% and 40%, respectively, of the boron in trees in the healthy stands and 37% in the boron-deficient stand. Only 11–13% of the tree boron was in the needles. The amount of nitrogen bound in the ecosystem studied was 2.1 and 2.5Mgha⁻¹, respectively, in the two healthy stands and 3.0Mgha⁻¹ in the boron deficient stand. In the ecosystem the trees contained 21–29% of the amount of nitrogen. Stems contained 14–24%, respectively, and needles 26–36%, respectively, of the nitrogen in the trees on the studied stands. In stem-only harvestings, relatively more boron than nitrogen would be removed from a site. In the boron-deficient stand, boron fertilisation for 3years nearly doubled the amount of boron in the ecosystem. Only 38% of the fertiliser boron (2kgha⁻¹) was found in the ecosystem components studied.
Agid:
553521