Effects of changes in traditional management on height and radial growth patterns in a Juniperus thurifera L. woodland

• Published in: Forest ecology and management Vol. 255; no. 3; pp. 506 - 512
• Main Authors: Olano, J.M., Rozas, V., Bartolomé, D., Sanz, D.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 20.03.2008; [Amsterdam]: Elsevier Science; Elsevier
• Subjects: age structure; Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Browsing; browsing pressure; dendrochronology; Dendroecology; Forest harvesting and working in forest; forest management; forest stands; forest trees; Forestry; Fundamental and applied biological sciences. Psychology; grazing pressure; growth rings; growth suppression; Juniperus thurifera; land use; land use change; logging; Selective logging; silvicultural practices; Spain; stand management; Synecology; Terrestrial ecosystems; tree age; tree growth; xeric regimes; Spain; Europe; Dendroecology; Selective logging; Juniperus thurifera; Browsing; Spain; Diameter increment; Forest zone; Tree; Ecology; Forest logging; Selective cutting; Woodland
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/j.foreco.2007.09.015

In order to understand the effects of changes in traditional forest management on Spanish juniper ( Juniperus thurifera L.) forest dynamics, height and radial growth patterns were studied in 107 juniper trees in Cabrejas del Pinar (Soria, Central Spain). Suppressions in height and radial growth were common until the second half of XIXth century. These suppressions occurred at relatively low tree heights, and affected 30% of the sampled trees. The individual suppressions ended abruptly with a sharp increase in height and radial growth. These results fit well into the browsing cessation model, suggesting that an intense browsing pressure shaped this forest. The timing in the reduction of the browsing pressure matches the regional decrease in transhumant livestock that occurred in Spain during the second half of XIXth century. No difference in height-growth rate between suppressed and non-suppressed trees was observed for post-suppression period, indicating a high recovery capacity for J. thurifera. We observed a high variability in height-growth rate during post-suppression periods. This variability was poorly related to site factors (competition, landform), being related to tree life (age and presence of past suppression events). Traditional logging based solely on trees morphological traits may be partially responsible of this pattern.