Petersson, Linda
(2019).
Promoting natural regeneration of oak by manipulating disturbance.
Diss. (sammanfattning/summary)
Alnarp :
Sveriges lantbruksuniv.,
Acta Universitatis Agriculturae Sueciae, 1652-6880
; 2019:66
ISBN 978-91-7760-450-1
eISBN 978-91-7760-451-8
[Doctoral thesis]
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PDF
- Published Version
1MB |
Abstract
Oak regeneration is thought to be promoted by natural disturbance and past management practices that create semi-open conditions, such as periodic livestock grazing and lowintensity fire. The overall goal of this thesis was to examine whether disturbance factors can promote natural oak regeneration. The first study quantified demographic changes in the Swedish oak (Qurecus robur and Q. petraea) population and examined the role of altered land use for these changes. Despite a continuous increase in large oak trees in southern Sweden since 1953, oak saplings declined continuously after the early 1980s. This development was connected to widespread changes in land use and game management that created darker forests with more herbivores, likely reducing oak regeneration at a regional scale. Field experiments showed negative effects of present ungulate browsing pressure on oak seedlings and saplings. The combination of competing woody vegetation and browsing had greater negative effects on oak (Q. robur) survival than individual effects of either factor. Although woody vegetation provided some protection against ungulate browsing, the long-term effect on oak survival and growth was overall negative. Oak seedlings (Q. robur and Q. alba) displayed a high sprouting capacity following shoot-destructive disturbance (artificial clipping) in a greenhouse experiment. A field experiment including low-intensity fire and oak seedlings (Q. robur and Q. petraea) gave similar results. Greater light availability increased oak performance in both cases, suggesting that their tolerance to disturbance, such as browsing and low-intensity fire, is greater in high light environments. These results also indicate that fire could promote oak regeneration in temperate Europe, consistent with the North American fire-oak hypothesis. However, further research is needed to determine the long-term vitality of these oaks and their main competitors, and whether oaks gain competitive advantages after such disturbance. Oak-dominated forests are important for biodiversity and the effects of fire on species and communities also needs to be studied. In conclusion, the results suggest that in the absence of natural disturbance, active management that resemble previous disturbance regimes and restore habitats with semi-open canopies, and low to moderate browsing pressure, seem essential to promote natural oak regeneration.
Authors/Creators: | Petersson, Linda | ||||||||||
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Title: | Promoting natural regeneration of oak by manipulating disturbance | ||||||||||
Alternative abstract: |
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Series/Journal: | Acta Universitatis Agriculturae Sueciae (1652-6880) | ||||||||||
Year of publishing : | 2019 | ||||||||||
Volume: | 2019:66 | ||||||||||
Number: | 2019:66 | ||||||||||
Number of Pages: | 54 | ||||||||||
Papers/manuscripts: |
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Place of Publication: | Alnarp | ||||||||||
Publisher: | Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences | ||||||||||
ISBN for printed version: | 978-91-7760-450-1 | ||||||||||
ISBN for electronic version: | 978-91-7760-451-8 | ||||||||||
ISSN: | 1652-6880 | ||||||||||
Language: | English | ||||||||||
Publication Type: | Doctoral thesis | ||||||||||
Article category: | Other scientific | ||||||||||
Full Text Status: | Public | ||||||||||
Agris subject categories.: | F Plant production > F40 Plant ecology K Forestry > K10 Forestry production | ||||||||||
Subjects: | (A) Swedish standard research categories 2011 > 1 Natural sciences > 106 Biological Sciences (Medical to be 3 and Agricultural to be 4) > Ecology (A) Swedish standard research categories 2011 > 4 Agricultural Sciences > 401 Agricultural, Forestry and Fisheries > Forest Science | ||||||||||
Keywords: | browsing, competition, oak, disturbance, fire, light, natural regeneration, seedling, ungulate | ||||||||||
URN:NBN: | urn:nbn:se:slu:epsilon-p-102124 | ||||||||||
Permanent URL: | http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-p-102124 | ||||||||||
ID Code: | 16399 | ||||||||||
Faculty: | S - Faculty of Forest Sciences | ||||||||||
Department: | (S) > Southern Swedish Forest Research Centre | ||||||||||
Deposited By: | SLUpub Connector | ||||||||||
Deposited On: | 22 Oct 2019 10:37 | ||||||||||
Metadata Last Modified: | 22 Oct 2019 10:37 |
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