The first soil dataset from across the eight Biomass Connect Demonstrator Hub sites has now been published. This dataset contains the baseline measurements of key soil properties, including carbon, bulk density and pH, which are critical to assess the impacts of biomass crops on soils through future repeat sampling. The influence of soil characteristics on establishment success and performance of different biomass species will also be explored across the differing soils of the sites.
Sampling was completed in autumn 2022 before any ground preparation for planting. In addition, rather than take samples from random locations across each site, sampling focused on the pre-determined blocks and plots where different crops were to be planted, as well as sampling adjacent land as a reference. This means, with soil properties often differing across fields, that any crop-specific soil changes can be captured more robustly at each site.
The fieldwork campaign involved lots of hammering, with 40 to 45 soil cores taken at each Demonstrator Hub site. Cores were split into 0-15 cm and 15-30 cm depths in the field, and where a distinct subsoil horizon was encountered (i.e. below the plough layer) this was separated for subsequent analyses. The soil samples were transported back to the labs at Lancaster where the team spent several months drying, sieving, weighing, grinding and analysing.
- Hammering a soil core at the North Wyke Demonstrator Hub site.
- Coring equipment and bagged sample at a sampling location at the BGI Demonstrator Hub site.
- Air-dried and sieved soil sample.
The Hub sites represent previous arable and grassland uses, with the former generally having lower soil carbon concentrations in the 0-15 cm increments (Table 1). There is a predominance of sandy clay loam and clay loam texture classes across the sites, and one site consistently sandy loam texture (Table 1), though texture class varied more across individual samples for a few sites.
The remaining air-dried soil samples from the baseline campaign have been archived in the UKCEH Soil Bank so are available for further analyses or application of new techniques. In addition, sub-samples from each location were frozen at –20°C, providing an opportunity to undertake molecular analysis of soil biodiversity.
Table 1. Summary of Hub site previous land use and soils (0-15 cm samples).
Demonstrator Hub | Previous land use | % C (min – median – max) | Predominant texture class |
Auchincruive (Ayrshire) | Arable | 2.8 – 5.6 – 26.9* | Sandy loam |
Boghall Farm (Edinburgh) | Arable | 2.2 – 3.2 – 3.9 | Sandy clay loam |
Hillsborough (NI) | Grassland | 3.2 – 5.5 – 6.9 | Sandy clay loam |
Cockle Park Farm (Northumberland) | Arable | 1.8 – 2.0 -2.7 | Sandy clay loam |
Headley Hall (North Yorkshire) | Arable | 1.0 – 1.5 – 3.1 | Sandy clay loam |
IBERS (Aberystwyth) | Grassland | 5.0 – 6.3 – 8.0 | Sandy clay loam |
BGI (Chesham) | Grassland | 2.4 – 3.4 – 5.3 | Clay loam |
North Wyke (Devon) | Grassland | 4.6 – 6.9 – 8.9 | Clay loam |
*High values linked to coal waste residue from historic infrastructure