Home About Browse Search

Disturbance, nutrient availability and plant growth in phenol-rich plant communities

Berglund, Linda (2004). Disturbance, nutrient availability and plant growth in phenol-rich plant communities. Diss. (sammanfattning/summary) Umeå : Sveriges lantbruksuniv., Acta Universitatis Agriculturae Sueciae. Silvestria, 1401-6230 ; 327
ISBN 91-576-6711-X
[Doctoral thesis]

[img] PDF


Disturbances, such as fire, usually result in a higher N and nutrient availability. However, little is known regarding the role of fire-produced charcoal and other disturbance-induced effects on nutrient availability and the consequences for plant growth and ecosystem development. Late-successional boreal forests and subarctic forest-tundra ecotones are dominated by plants with high tissue-levels of phenolic compounds and have large quantities of N locked up in thick humus-layers. Factorial experiments were set up in both field and laboratory, manipulating amount of phenol-rich litter, charcoal and glycine. Nitrogen mineralization, nitrification, soluble P and phenolic compounds were measured by ionic and non-ionic resin capsules. Nitrogen-fixation was measured by acetylene reduction assays. Removal of phenol-rich litter with the charcoal-layer intact in a recently burned stand increased growth and nutrient uptake by tree seedlings, with birch (Betula pendula) being the most responsive species. Litter and charcoal may function synergistically thus influencing seedling establishment after fire, especially in early-successional species like birch. Nitrification-rates increased with addition of activated carbon (AC) (as a surrogate for fire-produced charcoal) in laboratory incubations of boreal and subarctic soils and phenolic accumulation on non-ionic resin-capsules was reduced by AC amendments. Nitrogen-fixation rates were found to increase linearly with time since fire. This increase was likely a function of the degree of colonization by cyanobacteria and site factors such as light, moisture and available N. Nitrogen addition rates of 4 Kg N ha -1 yr-1 eliminated Nfixation in late succession sites. The findings suggest that N-fixation in boreal forests becomes more important in late secondary succession were available N are low in spite of higher total N. Subarctic birch-forests had higher soluble P and phenol concentrations compared to heath tundra. In contrast, there were no differences in available NH4 + or NO3 -. The addition of glycine greatly enhanced N-mineralization rates in birch forests and heath tundra, suggesting severe N-limitation. Anthropogenic disturbances resulting in the loss of birch would greatly reduce positive influences from birch and increase soil-erosion and nutrient losses, creating both reduced N and P availability. I conclude that a drastically altered disturbance regime in boreal and subarctic regions, both decreased (e.g. reduction of fire) and increased (e.g land-use), may have profound long-term effects on ecosystem processes.

Authors/Creators:Berglund, Linda
Title:Disturbance, nutrient availability and plant growth in phenol-rich plant communities
Series Name/Journal:Acta Universitatis Agriculturae Sueciae. Silvestria
Year of publishing :September 2004
Number of Pages:33
ALLI. L.M. Berglund, T.H.DeLuca, O. Zackrisson. 2004. Activated carbon amendments to soil alters nitrification rates in Scots pine forests. (Soil Biology & Biochemistry, in press) II. L.M. Berglund. The effect of charcoal and polyphenolic-rich litter on growth and nutrient acquisition of boreal tree seedlings after fire. (Manuscript) III. O. Zackrisson, T.H. DeLuca, M-C Nilsson, A. Sellstedt, L.M Berglund. 2004. Nitrogen-fixation increase with successional age in boreal forest. (Ecology, in press) IV. L.M. Berglund, T.H. DeLuca, O. Zackrisson. Soil Nitrogen and phosphorus turnover in subartic ecosystems. (Manuscript)
Place of Publication:Umeå
ISBN for printed version:91-576-6711-X
Publication Type:Doctoral thesis
Full Text Status:Public
Agris subject categories.:F Plant production > F40 Plant ecology
F Plant production > F62 Plant physiology - Growth and development
Subjects:Not in use, please see Agris categories
Agrovoc terms:charcoal, phenolic compounds, plant litter, mineralization, nitrification, nitrogen fixation, fire ecology, ecological succession, boreal forests
Keywords:Charcoal, phenols, litter, N mineralization, nitrification, nitrogen fixation, fire, succession, mountain birch
Permanent URL:
ID Code:638
Department:(S) > Institutionen för skoglig vegetationsekologi (930701-061231)
Deposited By: Kristina Johansson
Deposited On:22 Sep 2004 00:00
Metadata Last Modified:02 Dec 2014 10:06

Repository Staff Only: item control page


Downloads per year (since September 2012)

View more statistics