Charcoal Application to Arable Soil: Effects on CO₂Emissions

Abstract

Activated carbon and commercial household charcoal were added to soil in a 36-day incubation study at 20 • C measuring carbon dioxide evolution. The black carbon materials were found to decompose slowly, releasing between 1.4% and 0.8% of their carbon content per year, respectively. The main experiment tested whether the black carbon additions to soil (2% and 4% by mass) affected decomposition of selected substrates in soil, both respiration dynamics and total respiration. The results indicated that the black carbon materials tested had no effect on total respiration from added glucose. However, decomposition rates of amylose, xylan, casein, and ryegrass were reduced in soil with addition of activated carbon but were not significantly affected by household charcoal. A larger surface area of activated carbon than that of household charcoal, and thus a greater adsorption capacity for organic compounds and exo-enzymes required to break down water-insoluble substrates, may explain the results.

Vertical and lateral transport of biochar in light-textured tropical soils

“…The unrecovered BC of at least 24% in the top 20 cm of soil can be attributed to (i) loss due to decomposition, (ii) migration as solid BC or dissolved organic matter to soil layers below 20 cm depth, which were not sampled, and (iii) lateral loss due to both water and wind erosion of the surface soil. The decomposition rate of BC produced within the same temperature range as our BCs has been reported to be small, with values in the range of 1% yr À1 within the first year of application (Carlsson et al, 2012;Kuzyakov et al, 2009;Luo et al, 2011). Some of the studies e.g.…”

Biochar alters the soil microbiome and soil function: results of next‐generation amplicon sequencing across Europe

“…Different studies have observed increases in soil respiration (Kolb et al ., ; Zavalloni et al ., ; Belyaeva & Haynes, ; Castaldi et al ., ; Quilliam et al . ; Ventura et al ., ); although decreases (Dempster et al ., ; Paz‐Ferreiro et al ., ; Carlsson et al ., ) or no change have also been observed (Galvez et al ., ; Bamminger et al ., ).…”

“…Observed effects of biochar on edaphic microbial processes are often conflicting. Different studies have observed increases in soil respiration (Kolb et al, 2009;Zavalloni et al, 2011;Belyaeva & Haynes, 2011;Castaldi et al, 2011;Quilliam et al 2012;Ventura et al, 2014); although decreases (Dempster et al, 2011;Paz-Ferreiro et al, 2011;Carlsson et al, 2012) or no change have also been observed (Galvez et al, 2012;Bamminger et al, 2014).…”

“…Environmental measurements in the UK time series suggest no change in respiration due to biochar over the year. Previous work has indicated that biochar application either increases microbially mediated respiration (Belyaeva & Haynes, 2011;Castaldi et al, 2011) or can in some cases retard it (Dempster et al, 2011;Carlsson et al, 2012). It is possible that this is a result of differences in methodology, given that respiration rates are often measured through use of incubation experiments (Kolb et al, 2009;Belyaeva & Haynes, 2011;Zavalloni et al, 2011).…”

From agricultural use of sewage sludge to nutrient extraction: A soil science outlook

“…Although biochar from organic residues principally can be used as a soil improving product (e.g. Carlsson et al 2012 ; Parvage et al 2013 ), metal contents in biochar from sewage sludge are too high (e.g. Song et al 2014 ) and similar to ash limiting its use as a soil amendment.…”