Legacy effects override soil properties for CO 2 and N 2 O but not CH 4 emissions following digestate application to soil

Rosace, M.C., Veronesi, F., Briggs, S., Cardenas, L.M. and Jeffery, S. (2020) Legacy effects override soil properties for CO 2 and N 2 O but not CH 4 emissions following digestate application to soil. GCB Bioenergy, 12 (6). pp. 445-457.

[img]
Preview
Text
Simon Jeffery legacy effects upload.pdf - Published Version

Download (645kB) | Preview

Abstract

The application of organic materials to soil can recycle nutrients and increase organic matter in agricultural lands. Digestate can be used as a nutrient source for crop production but it has also been shown to stimulate greenhouse gas (GHG) emissions from amended soils. While edaphic factors, such as soil texture and pH, have been shown to be strong determinants of soil GHG fluxes, the impact of the legacy of previous management practices is less well understood. Here we aim to investigate the impact of such legacy effects and to contrast them against soil properties to identify the key determinants of soil GHG fluxes following digestate application. Soil from an already established field experiment was used to set up a pot experiment, to evaluate N2O, CH4 and CO2 fluxes from cattle‐slurry‐digestate amended soils. The soil had been treated with farmyard manure, green manure or synthetic N‐fertilizer, 18 months before the pot experiment was set up. Following homogenization and a preincubation stage, digestate was added at a concentration of 250 kg total N/ha eq. Soil GHG fluxes were then sampled over a 64 day period. The digestate stimulated emissions of the three GHGs compared to controls. The legacy of previous soil management was found to be a key determinant of CO2 and N2O flux while edaphic variables did not have a significant effect across the range of variables included in this experiment. Conversely, edaphic variables, in particular texture, were the main determinant of CH4 flux from soil following digestate application. Results demonstrate that edaphic factors and current soil management regime alone are not effective predictors of soil GHG flux response following digestate application. Knowledge of the site management in terms of organic amendments is required to make robust predictions of the likely soil GHG flux response following digestate application to soil.

Item Type: Article
Keywords: carbon dioxide, digestate, legacy effects, methane, nitrous oxide, soil gas flux
Divisions: Crop and Environment Sciences
Depositing User: Ms Kath Osborn
Date Deposited: 02 Jun 2020 09:58
Last Modified: 02 Jun 2020 09:58
URI: http://hau.repository.guildhe.ac.uk/id/eprint/17555

Actions (login required)

Edit Item Edit Item