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GCB Bioenergy

Cover image for Vol. 10 Issue 2

Edited By: Steve Long

Impact Factor: 4.655

ISI Journal Citation Reports © Ranking: 2016: 2/83 (Agronomy); 18/92 (Energy & Fuels)

Online ISSN: 1757-1707

Associated Title(s): Global Change Biology

Impacts of biochar on soil faunal communities and linked ecosystem processes


Impact of forest biomass-based electricity generation

Biochar is the solid carbon-rich product of pyrolysis of biomass crops. The use of bioenergy created by pyrolysis can reduce carbon dioxide (CO2) emissions by offsetting fossil fuel use. Additionally, biochar, when added to the soil, can aid in carbon sequestration (i.e. long-term carbon storage). Consequently, biochar amendment of soil is a strategy at the forefront of attempts to offset anthropogenic CO2 emissions, especially when applied to bioenergy cropland. Little is known, however, about the impact of biochar amendment on soil faunal communities.

According to McCormack and coauthors, previous studies on this topic have been chiefly observational, and often report contrasting results, thus adding little mechanistic understanding of biochar and bioenergy cropping impacts on soil organisms and linked ecosystem processes. This means it is difficult to predict, or control for, changes in biotic carbon cycling arising from biochar and bioenergy cropping.

The authors reviewed literature with a focus on the impact of biochar deployed in perennial bioenergy crop systems (e.g. short-rotation coppice, SRC, and perennial grasses, Miscanthus and switchgrass), which represent the greatest divergence from current agricultural management such as annual crops like corn. Their objective was to describe how soil fauna contributes to critical ecosystem processes and determine how this ecology may be altered by biochar and bioenergy cropping impacts on food resources, niche availability and interspecific interactions.


The authors first outlined potential abiotic (soil quality-mediated) shifts in the soil environment under implementation of biochar and bioenergy cropping the resulting effects on the abundance, diversity, and composition of soil faunal communities. They then speculated on how the implementation of combined biochar and bioenergy cropping would affect abiotic soil properties. Some effects of combined biochar and bioenergy cropping were predicted to be competitive, some synergistic, and others uncertain. For example, bioenergy cropping can potentially reduce soil contaminants and are therefore likely to promote more species rich soil communities. Biochar’s high cation exchange capacity can reduce soil contamination via the immobilization of heavy metals and pollutants. However, biochar may also be a source of contaminants depending on feedstock, pretreatment and production.

The authors then outlined biotic (plant- and microbe-mediated) shifts in the soil environment under implementation of biochar and bioenergy cropping and their implications for soil faunal communities. Again, some plant-mediated and microbe-mediated effects of combined biochar and bioenergy cropping were predicted to be competitive, some synergistic, and others uncertain.

Lastly, the authors then explored current research on the effect of biochar application and bioenergy cropping on soil fauna. The results were inconclusive because the reaction of soil fauna to biochar application and bioenergy cropping varied across taxa and by crop, biochar
and soil type.

The authors offer recommendations for promoting biologically diverse, fertile soil via biochar use in bioenergy crop systems, accompanied by specific future research priorities. Greatest benefits would be gained from using specific production processes to produce biochar with specific characteristics that correspond to the soil properties that need to be improved. They encourage more research in this area in order to enhance our ability to manage land for the provision of multiple ecosystem services: carbon sequestration, food cultivation and energy production, while supporting diverse aboveground and belowground communities.

McCormack SA, Ostle N, Bardgett RD, Hopkins DW, Vanbergen AJ (2013) Biochar in bioenergy cropping systems: impacts on soil faunal communities and linked ecosystem processes. GCB Bioenergy, 5, 81–95. DOI: 10.1111/gcbb.12046 Read this paper

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