The influence of N load and harvest intensity on the risk of P limitation in Swedish forest soils
Författare
Summary, in English
Nitrogen (N) is often considered to be the major factor limiting tree growth in northern forest ecosystems. An increased N availability, however, increases the demand for other nutrients such as base cations and phosphorous (P) which in turn may change which nutrient is the limiting factor. If P or base cations become limiting, N will start to leach which means a risk of increased eutrophication of surface waters. As many studies focus on base cations, this study instead aims at estimating P budgets on a regional scale for different harvesting scenarios relevant for Swedish conditions. P budget calculations were carried out for 14,550 coniferous sites from the Swedish National Forest Inventory, as weathering+deposition-harvesting-leaching. Three scenarios with different harvest intensities were used: 1) no harvesting, 2) stem harvesting and 3) whole-tree harvesting. The input data were derived from measurements and model results. The P budget estimates indicate that harvesting, especially whole-tree harvesting, result in net losses of P in large parts of Sweden. The highest losses were found in southern Sweden due to high growth rate in this area. In the whole-tree harvesting scenario the losses exceeded 1 kg ha(-1)y(-1) on many sites. N budget calculations on the same sites indicate that N generally accumulates in the whole country and especially in the southern parts. Consequently, the N and P budget calculations indicate that the forests in southern Sweden are in a transition phase from N-to P-limitation to growth. This transition will proceed as long as the accumulation of N continues. These results are important in a sustainable forestry context, as a basis for assessing the risk of future N leaching, and in designing recommendations for abatement strategies of N deposition and for application of wood ash recycling and N fertilization. (C) 2007 Elsevier B.V. All rights reserved.
Publiceringsår
2008
Språk
Engelska
Sidor
284-289
Publikation/Tidskrift/Serie
SCIENCE OF THE TOTAL ENVIRONMENT
Volym
404
Issue
2-3
Länkar
Dokumenttyp
Konferensbidrag
Förlag
Elsevier
Ämne
- Environmental Sciences
Nyckelord
- Harvesting
- Sweden
- Forest soils
- Budget
- Phosphorous
- Nitrogen
- Weathering
Conference name
5th International Symposium on Ecosystem Behavior
Conference date
2006-06-25 - 2006-06-30
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1879-1026
- ISSN: 0048-9697