Abstract

Are current estimates of silicate minerals weathering rates precise enough to predict whether nutrient pools will recover after forest harvesting? Answering this question seems crucial for sustainable forestry practices on silicate dominated soils. In this paper, we synthesize estimated Ca and K weathering rates (derived using seven different approaches) from a forested area in northern Sweden (the Svartberget-Krycklan catchment) to evaluate the precision of weathering rate estimates. The methods were: mass-balance budgets (catchment and pedon-scale); long-term weathering losses inferred from weathered soil profiles (using zirconium as a conservative tracer); strontium isotopes (Sr-86/Sr-85) as proxy for catchment export of geogenic Ca; climate based regressions; a steady-state, process-based weathering model (PROFILE) and a dynamic, conceptual catchment geochemistry model (MAGIC). The different methods predict average weathering rates of 0.67 +/- 0.71 g Ca m(-2) year(-1) (mean +/- stdev) and 0.39 +/- 0.38 g K m(-2) year(-1), suggesting a cumulative weathering release during a forest rotation period of 100 years that is the same magnitude as losses induced by forest harvesting at the end of the period. Clearly, forestry practices have the capacity to significantly alter the long-term nutrient status of the soil and cation concentrations in soil-water runoff. However, the precision in weathering estimates are lower than that needed to distinguish between effects on nutrient pools by different forest practices (complete-tree harvesting versus conventional stem only harvest). Therefore, we argue that nutrient budgets, where weathering rates play a crucial role, cannot be used as basis for resolving whether different harvesting techniques will allow nutrient pools to recover within one rotation period. Clearly, this hampers the prerequisite for sound decision making regarding forestry practices on silicate mineral dominated soils. (C) 2010 Elsevier B.V. All rights reserved.

Keywords

Weathering rates; Boreal forest; Methods; Decision making

Published in

Forest Ecology and Management
2011, Volume: 261, number: 1, pages: 1-9
Publisher: ELSEVIER SCIENCE BV

SLU Authors

• Klaminder, Jonatan

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    

• Lucas, Richard

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    

• Futter, Martyn

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

• Bishop, Kevin

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

• Köhler, Stephan

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

• Egnell, Gustaf

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    

• Laudon, Hjalmar

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    

Associated SLU-program

SLU Future Forests


Sustainable Development Goals

Protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss


UKÄ Subject classification

Environmental Sciences related to Agriculture and Land-use


Publication identifier

DOI: https://doi.org/10.1016/j.foreco.2010.09.040

Permanent link to this page (URI)

https://res.slu.se/id/publ/58891