Effect of soil waterlogging on below‐ground biomass allometric relations in Norway spruce

Abstract

An increasing importance is assigned to the estimation and verification of carbon stocks in forests. Forestry practice has several long‐established and reliable methods for the assessment of above‐ground biomass; however, we still miss accurate predictors of below‐ground biomass. A major windthrow event exposing the coarse root systems of Norway spruce trees allowed us to assess the effects of contrasting soil stone and water content on below‐ground allocation. Increasing stone content decreases the root/shoot ratio, while soil waterlogging leads to an increase in this ratio. We constructed allometric relationships for below‐ground biomass prediction and were able to show that only soil waterlogging significantly impacts model parameters. We showed that diameter at breast height is a reliable predictor of below‐ground biomass and, once site‐specific parameters have been developed, it is possible to accurately estimate below‐ground biomass in Norway spruce.

Keywords:

• Below‐ground stump
• coarse roots
• Picea abies
• soil stoniness
• waterlogging

Acknowledgments

We thank Prof. Jozef Konôpka for helping with the plot selection and experimental design and Dr. Brian Tobin for comments on the manuscript. We acknowledge Mr Miroslav Lipnický and Ondrej Kolenič for technical and logistic assistance. This research was supported by the Slovak Research and Development Agency (“Vulnerability of forest ecosystems destabilized by wind to the impact of some disturbance factors” APVV‐0612‐07 project).