Biochar-mediated changes in soil quality and plant growth in a three year field trial
Författare
Summary, in English
While many laboratory studies have focused on the short term effects of biochar addition to soil), there have been comparatively few tracing its longer term effects in the field. This study investigated the multiyear impact of biochar on crop performance and soil quality with specific emphasis on carbon (C) and nitrogen (N) cycling over a 3 y period. Biochar was added to an agricultural field at 0, 25 and 50 t ha(-1) and planted with maize (year 1) and grass (years 2 and 3). Biochar addition affected plant performance in the grass crop with significant increases in foliar N (year 2) and above-ground biomass (year 3). Below-ground, biochar increased soil respiration, fungal and bacterial growth rate and turnover in year 2. This change coincided with a shift toward a bacterial dominated decomposer community, suggesting a decrease in the potential for microbially mediated C sequestration. Biochar did not affect dissolved organic C (DOC) and N (DON), NO3- or NH4+ pool sizes. Similarly, biochar addition had limited effects on the turnover of C-14-labelled SOC (plant litter), DOC (sugars and organic acids) and DON (amino acids) and no long term effect on N mineralization, NH3 volatilization, denitrification and NH4+ sorption. After 3 years in the field, the alkalinity associated with the biochar had been fully neutralized and biochar lost most of its cations (K, Na, Ca) but had built up an associated microbial community. We conclude that biochar addition to soil causes small and potentially transient changes in a temperate agroecosystem functioning. Importantly, many of the short-term effects of biochar on plant growth and soil behavior reported from laboratory studies were not observed in the field emphasizing the need for long term field trials to help inform agronomic management decisions involving biochar. (C) 2011 Elsevier Ltd. All rights reserved.
Avdelning/ar
Publiceringsår
2012
Språk
Engelska
Sidor
113-124
Publikation/Tidskrift/Serie
Soil Biology & Biochemistry
Volym
45
Dokumenttyp
Artikel i tidskrift
Förlag
Elsevier
Ämne
- Biological Sciences
Nyckelord
- Black carbon
- Black nitrogen
- Carbon sequestration
- Charcoal
- Soil
- organic matter
- Climate change mitigation
Status
Published
Projekt
- Interaction between fungi and bacteria in soil
- Microbial carbon-use efficiency
Forskningsgrupp
- Microbial Ecology
ISBN/ISSN/Övrigt
- ISSN: 0038-0717