Sammanfattning

There is a growing societal demand to increase the use of forest biomass for substitution of fossil fuels. The production of this biomass must be sustainable and an indicator for critical biomass harvesting (CBH) has been suggested in order to sustain forest soil fertility and mitigate soil acidification at whole-tree harvesting. The CBH indicator is based on an acidity mass balance approach in line with the critical load of acid deposition (CL) concept. Countries like Sweden, the Netherlands and the state of Quebec, Canada apply such mass balance approaches for developing forest biomass harvesting guidelines. The implementation of this type of policy instrument may restrict the use of harvest residues for bioenergy and thereby the substitution of fossil fuels. It may as well affect the forestry sector revenue negatively. To maintain credibility for enforced limitations, it is important that the risk assessment and suggested policy implications are based on solid scientific methods and assumptions. The mass balance approach have been criticized for being too uncertain and not sufficiently validated for being used to guide ecosystem management. In this paper we use published Swedish data on soils, acid deposition, forest production and information from international scientific literature to critically examine the CBH indicator. We conclude that the CBH indicator 1) does not account for all relevant processes 2) it exaggerates the sensitivity and correlates poorly to actual forest soil acid-base status and edaphic conditions and 3) data availability does not allow the indicator to be calculated at a high enough spatial resolution for advice on management for forest owners. The concerns for the mass-balance approach and CBH indicator are discussed in an international perspective.

Nyckelord

Acidity mass-balance; Forest biomass harvesting; Soil acidity; Soil nutrient depletion; Critical biomass harvest

Publicerad i

Ecological Indicators
2021, Volym: 132, artikelnummer: 108310
Utgivare: ELSEVIER

SLU författare

• Löfgren, Stefan

  • Institutionen för vatten och miljö, Sveriges lantbruksuniversitet
    

• Stendahl, Johan

  • Institutionen för mark och miljö, Sveriges lantbruksuniversitet
    

• Karltun, Erik

  • Institutionen för mark och miljö, Sveriges lantbruksuniversitet
    

Globala målen

SDG7 Säkerställa tillgång till ekonomiskt överkomlig, tillförlitlig, hållbar och modern energi för alla
SDG15 Skydda, återställa och främja ett hållbart nyttjande av landbaserade ekosystem, hållbart bruka skogar, bekämpa ökenspridning, hejda och vrida tillbaka markförstöringen samt hejda förlusten av biologisk mångfald


UKÄ forskningsämne

Markvetenskap
Skogsvetenskap


Publikationens identifierare

DOI: https://doi.org/10.1016/j.ecolind.2021.108310

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/114505