Biochar application differentially affects soil micro-, meso-macro-fauna and plant productivity within a nature restoration grassland

Soil Biology and Biochemistry, vol. 174, pp. 108789

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.

Authors 9

1. Simon Jeffery corresponding

   Harper Adams University

   Affiliation as printed

   Agriculture and Environment Sciences Department, Harper Adams University, Newport, Shropshire, TF10 8NB, United Kingdom

2. Tess F. J. van de Voorde

   Wageningen University & Research

   Affiliation as printed

   Plant Ecology and Nature Conservation Group, Wageningen University, P.O. Box 47, 6700AA, Wageningen, the Netherlands

3. W. E. Harris

   Harper Adams University

   Affiliation as printed

   Agriculture and Environment Sciences Department, Harper Adams University, Newport, Shropshire, TF10 8NB, United Kingdom

4. Liesje Mommer

   Wageningen University & Research

   Affiliation as printed

   Plant Ecology and Nature Conservation Group, Wageningen University, P.O. Box 47, 6700AA, Wageningen, the Netherlands

5. Jan Willem van Groenigen

   Wageningen University & Research

   Affiliation as printed

   Soil Biology Group, Wageningen University, P.O. Box 47, 6700AA, Wageningen, the Netherlands

6. Gerlinde B. De Deyn

   Wageningen University & Research

   Affiliation as printed

   Soil Biology Group, Wageningen University, P.O. Box 47, 6700AA, Wageningen, the Netherlands

7. Flemming Ekelund

   University of Copenhagen

   Affiliation as printed

   Department of Biology, Terrestrial Ecology Section, University of Copenhagen, Universitetsparken 15, 2100 København Ø, Denmark

8. María J.I. Briones

   Universidade de Vigo

   Affiliation as printed

   Departmento de Ecología y Biología Animal, Universidad de Vigo, 36310, Vigo, Spain

9. Т. Martijn Bezemer Aachen Institute of Biology Section Plant Ecology and Phytochemistry

   Leiden University · Netherlands Institute of Ecology

   Affiliation as printed

   Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, 6700AB, Wageningen, the Netherlands

   Institute of Biology, Section Plant Ecology and Phytochemistry, Leiden University, P.O. Box 9505, 2300 RA, Leiden, the Netherlands