Limited effect of wood ash application on soil quality as indicated by a multisite assessment of soil organic matter attributes. Issue 5 (20th February 2022)

• Record Type: Journal Article
• Authors: Joseph, Ruth; Diochon, Amanda; Morris, Dave; Venier, Lisa; Emilson, Caroline E.; Basiliko, Nathan; Bélanger, Nicolas; Jones, Trevor; Markham, John; Rutherford, Michael P.; Smenderovac, Emily; Van Rees, Ken; Hazlett, Paul
• Is Part Of: Global change biology. Volume 14:Issue 5(2022)
• Page Start: 500
• Page End: 521
• Publication Date: 2022-02-20
• Subjects: bioenergy -- bottom ash -- fly ash -- forest soil -- labile carbon -- microbial biomass -- soil carbon -- soil quality; Biomass energy -- Periodicals; Biomass energy -- Environmental aspects -- Periodicals; Energy crops -- Periodicals; 662.88
• DOI: 10.1111/gcbb.12928
• Languages: English
• ISSNs: 1757-1693

Abstract

Abstract: In Canada, the combustion of forest biomass for bioenergy production has been increasing with an associated increase in residual wood ash. Wood ash is typically landfilled as waste but there is growing interest in applying wood ash to the soils of commercial forests. Ideally, wood ash supplies nutrients that may have been removed through biomass harvesting, increases soil pH, which improves nutrient availability, and potentially improves site productivity, but there is also potential for detrimental effects, such as toxicity, that impair soil functions. The objective of this study was to investigate the effects of wood ash application on soil organic matter attributes at eight experimental sites across Canada that are examining the effects of wood ash application on site fertility, productivity, and soil biodiversity. Wood ash application had an effect on total carbon (TC) and total nitrogen, microbial biomass carbon (MBC), hot water extractable carbon (HWEC), mineralizable C, sand size C, and HWEC and MBC normalized to TC, but changes were typically restricted to single sites or differed in their direction, that is, positive or negative. Based on the limited and inconsistent effects of ash on established indictors of soil quality measured in this study, there does not appear to be any advantageous or detrimental effects of adding wood ash to forest soil quality. Abstract : Wood ash generation from bioenergy production is increasing and is often landfilled when it could be land applied to improve soil. Wood ash is alkaline and contains nutrients essential to plant growth, which may maintain or enhance soil quality. Across a broad geographic gradient, there were limited effects of wood ash application to soils at eight sites in Canada on the measured attributes of soil quality, which suggests that soil quality is not affected by wood ash application. Wood ash generation is growing and when it makes economic sense to apply it to forest soils, it should be encouraged.