Biochar application differentially affects soil micro-, meso-macro-fauna and plant productivity within a nature restoration grassland. (November 2022)

• Record Type: Journal Article
• Authors: Jeffery, Simon; van de Voorde, Tess F.J.; Harris, W. Edwin; Mommer, Liesje; Van Groenigen, Jan Willem; De Deyn, Gerlinde B.; Ekelund, Flemming; Briones, Maria J.I.; Bezemer, T. Martijn
• Is Part Of: Soil biology and biochemistry. Volume 174(2022)
• Publication Date: 2022-11
• Subjects: Biochar -- Soil fauna -- Microbial biomass -- PLFA -- Nature restoration -- Grassland -- Carbon sequestration; Soil biochemistry -- Periodicals; Soil biology -- Periodicals; Sols -- Biochimie -- Périodiques; Sols -- Biologie -- Périodiques; Sols -- Microbiologie -- Périodiques; Bodembiologie; Biochemie; 631.46
• DOI: 10.1016/j.soilbio.2022.108789
• Languages: English
• ISSNs: 0038-0717

Abstract

Abstract: Biochar is proposed as an option to sequester carbon (C) in soils and promote other soil-based ecosystem services. However, its impact on soil biota from micro to macroscale remains poorly understood. We investigated biochar effects on the soil biota across the soil food web, on plant community composition and on biomass production. We conducted a field experiment in a nature restoration grassland testing four treatments: two biochar types (herbaceous feedstock pyrolyzed at 400 °C or 600 °C – hereafter B400 and B600), and a positive (i.e. unpyrolysed biochar feedstock, hereafter Hay) and negative (no addition) control. Responses of plants and soil biota were evaluated one and three years after establishing the treatments. Soil pH and K concentrations increased significantly in the B600 treatment. Mite abundances were significantly higher in B400 whereas nematode abundances were highest in Hay (1st year) and lowest in B400 (3rd year). Other soil fauna groups (enchytraeids and earthworms) varied more between years than between treatments. Legume cover increased significantly in the biochar treatments but this effect was transient. Legumes, grasses and primary productivity also showed a statistically significant Treatment x Year interaction due to transitory effects that were no longer present by the 3rd year. Our results suggest that biochar produced from meadow cuttings and applied at the 10 t/ha rate cause transitory impacts on soil biota abundance and plant communities over the 3-year timeframe used for this experiment. Therefore, this type of biochar could potentially be used for soil carbon sequestration, with minimal impacts on soil biota abundance or diversity, within the groups studied here, or plant biodiversity and productivity. Further research is required to investigate the longer-term impacts of this potential soil C storage sink. Highlights: Biochar has differential effects on soil organisms by groups. Legume biomass increases following to biochar application. The impacts differ for different biochar types. Effects are transient and do not persist into the third season. Biochar has potential to sequester C in soils in nutrient rich grasslands.