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Background

Higher exportation of harvest residues from forests due to increased demand for woody biomass, has reportedly diminished soil mineral resources and may lead to degraded tree nutrition as well as growth. However, as nutrients become less available in the soil, the remobilization of nutrients in biomass tissues (plant internal cycling) helps sustain tree nutrition. Our study aims to quantify the impact of Removing Harvest Residues and Litter (RHRL) during five years on tree growth, wood density, and stem wood nutrient concentrations in young beech and oak forest stands.

Result

Our study found that, RHRL significantly decreased tree growth ring width by 14%, and wood density by 3%, in beech trees, in near bark rings. RHRL also significantly reduced nutrient concentration in near bark and near pith areas of both studied species. Mg, Na and S were found lower by 44%, 76%, and 56%, respectively, in near bark area of beech trees. In near bark area of oak trees, K, Ca, Mg, Na, S, and Fe were lower by 20%, 25%, 41%, 48%, 41%, and 16%, respectively. K and Mg concentrations decreased more strongly in near pith area compared to near bark area suggesting internal translocation of these two elements.

Conclusion

In beech trees, wood density proved to be an important factor while quantifying the effect of removing harvest residuals on tree growth and biomass. Soil nutrient loss intensified the remobilization of nutrients contained in older tree rings (close to the pith) towards newly formed rings (close to bark). In our study, in beech trees, K was found to be the most recycled major nutrient. These results demonstrate the potential of such analysis for providing valuable insight into the effect of RHRL in premature stands on the physiological adaptive strategies of trees and an indication of soil fertility status.


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Removing harvest residues from hardwood stands affects tree growth, wood density and stem wood nutrient concentration in European beech (Fagus sylvatica) and oak (Quercus spp.)

Show Author's information Sanjoy Roya( )Jean-Michel Lebana,b ( )Bernhard ZelleraGregory van der HeijdenaArnaud ReichardaMarie-Christine GehinaPhilippe Santenoisea,cLaurent Saint-Andrea
INRAE, BEF, F-54000 Nancy, France
IGN, Laboratoire de l'Inventaire Forestier, Nancy, F-54000, France
Université de Lorraine, AgroParisTech, INRAE, SILVA, F-54000 Nancy, France

Abstract

Background

Higher exportation of harvest residues from forests due to increased demand for woody biomass, has reportedly diminished soil mineral resources and may lead to degraded tree nutrition as well as growth. However, as nutrients become less available in the soil, the remobilization of nutrients in biomass tissues (plant internal cycling) helps sustain tree nutrition. Our study aims to quantify the impact of Removing Harvest Residues and Litter (RHRL) during five years on tree growth, wood density, and stem wood nutrient concentrations in young beech and oak forest stands.

Result

Our study found that, RHRL significantly decreased tree growth ring width by 14%, and wood density by 3%, in beech trees, in near bark rings. RHRL also significantly reduced nutrient concentration in near bark and near pith areas of both studied species. Mg, Na and S were found lower by 44%, 76%, and 56%, respectively, in near bark area of beech trees. In near bark area of oak trees, K, Ca, Mg, Na, S, and Fe were lower by 20%, 25%, 41%, 48%, 41%, and 16%, respectively. K and Mg concentrations decreased more strongly in near pith area compared to near bark area suggesting internal translocation of these two elements.

Conclusion

In beech trees, wood density proved to be an important factor while quantifying the effect of removing harvest residuals on tree growth and biomass. Soil nutrient loss intensified the remobilization of nutrients contained in older tree rings (close to the pith) towards newly formed rings (close to bark). In our study, in beech trees, K was found to be the most recycled major nutrient. These results demonstrate the potential of such analysis for providing valuable insight into the effect of RHRL in premature stands on the physiological adaptive strategies of trees and an indication of soil fertility status.

Keywords: Fagus sylvatica, Wood density, Dendroecology, Radial growth, Tree growth, Harvest residues, Quercus petraea, Dendrochemistry, Ring width, Translocation

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Published: 25 February 2022
Issue date: April 2022

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© 2022 Beijing Forestry University.

Acknowledgements

The authors are grateful to Dr. Serajis Salekin and Jeremie Bel for their insightful comments and kind support at different stages of the manuscript formation. This research was carried out in the laboratory Biogeochimie des Ecosystèmes forestier (BEF), INRAE (Institut national de la recherche agronomique), Champenoux, FR. The research benefited from the unit's established experimental sites and the in situ and laboratory facilities for data and sample collection as well as for spectrometry and mineral analysis. We also benefited from the Silvatech platform (a shared platform between Silva and BEF, INRAE) for X-ray scanning of wood cores and wood density measurements by image analysis. We also acknowledge the French National Research Agency through the Cluster of Excellence ARBRE (ANR-11-LABX-0002-01) and the mobile lab (M-POETE) of ANAEE-France (ANR-11-INBS-0001) for support on the experiment.

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