Biochar Deployment & Field Trials
From small scale ‘pot’ and small plot trials, to ensure soil health, through to whole field trials, the Biochar Demonstrator will be applying over 200 tonnes of biochar across the UK.
Pot and Mesocosm Experiments
To minimise unintended consequences of our large-scale trials, we are conducting a series of mesocosm experiments to identify potential risks. These experiments take a holistic approach to understand the impacts of adding biochar to soil at all scales and measure soil ecosystem services under controlled conditions. Our mesocosm experiments are also looking at co-amendments with other materials such as manures.
What are we measuring?
We are interested in how soils, and the ecosystem services they provide, respond to biochar addition. Ecosystem services are a broad collection of ‘functions’ that a soil provides that includes growing crops, nutrient cycling and sequestration, and supporting biodiversity. Therefore, we are measuring a comprehensive array of soil properties. These include both chemical and physical soil properties, for example pH and bulk density. Plus, we are monitoring the soil’s biology, looking at microbiology, invertebrates and plants: our measurements include crop yield and health, earthworm health, and microbial function and diversity.
Small Plot Trials
At our University of Nottingham and Bangor University sites we are conducting small plot trials of arable farmland and grassland. On these sites we can vary biochar application rate and composition to determine the impacts of different applications to ecosystem function. On our Bangor farm we are also investigating co-application with rock dust for enhanced rock weathering as an additional way to store carbon in soil.
Whole Field Trials
On arable farm sites across the midlands and grasslands in North Wales we will be establishing hectare permanent plots. We aim to apply biochar to a range of soil and tillage regimes, at an application rate of up to 10 tonnes per hectare. This work will explore the feasibility of using biochar in agricultural soils to help sequester carbon.
In collaboration with the National Forest, we have incorporated biochar into soil prior to tree planting. Different application methods have been trialled, including surface spreading and burial. Further forestry trials are expected to continue throughout the project.
Contaminated soils and difficult to vegetate sites, such as sewage sludge disposal sites, denuded railway embankments and open cast coal mines will also be trialled for biochar application. Biochar can potentially help in the remediation of soils by adsorbing contaminants to its surface and reducing their bioavailability to plants and soil organisms.