Thursday, August 22, 2019

£1m soil health project issues latest progress report

March 5, 2019 by  
Filed under News & Business

Farmers who haven’t yet done so this year are being urged to conduct a soil health check.

It follows the latest update by researchers working on a £1m project to improve soil health. The five-year Soil Biology and Soil Health Partnership is funded by the Agriculture and Horticulture Development Board and the British Beet Research Organisation.

One ambition of the partnership is to produce a toolkit to help farmers and growers measure and manage soil status. The team is developing a range of physical, chemical and biological indicators  that can be used to keep land in good condition for growing crops.

Routine soil healthy indicators include measures such as acidity and nutrients. But the researchers are also harnessing less common indicators – including loss on ignition, respiration, microbial biomass carbon and potentially mineralisable nitrogen.

Soil scorecard

Researchers are also developing a scorecard listing the soil health indicators and the values they  generate. Based on known threshold values, these results can be colour coded using a traffic-light system to highlight the aspects of soil health requiring most attention.

A network of seven experimental sites is being used to develop the scorecard approach. Sites were selected to represent a range of soil management histories, soil types, soil organic matter additions, acidity, drainage, climatic conditions and rotations.

A prototype soil health scorecard, using a subset of indicators, was tested at one of these sites in 2018. The sandy loam site, located at Harper Adams in Shropshire, provided an extreme test, as it had a long history of repeat organic material additions.

The strength in the scorecard is that it breaks down the challenge of improving soil health into manageable pieces. It can focus attention and guide management interventions to improve the overall health status of the soil.

Innovation groups

Compared with manufactured fertiliser, the scorecard showed that organic material additions improved soil chemical properties as well as soil organic matter content. Extractable phosphate was also shown to be relatively high across the whole site, as was bulk density.

The scorecard will now be refined and tested across the experimental sites and in consultation with eight farmer research innovation groups. The work will result in a set of indicators to measure soil health in the field directly or indirectly – though sending samples away for analysis.

Critically, the researchers will also improve understanding of the relationship between each component of soil health and crop yields. One of the most exciting areas is the development of more robust indicators, benchmarks and thresholds for biological properties, they say.

The 2018 annual report also includes details of innovative developments in molecular biology that are yielding ways to measure the soil biological community, including the presence and distribution of soil-borne pathogens.