Long term Biochar Agronomic Field Trial

Title of Experiment: Long term Biochar Agronomic Field Trial

Date planted: May 2009

Contact: Prof Davey Jones

Funding source: European Union SEREN programme, European Union KESS programme.

Location: Henfaes Research Centre (lowland site)

Experimental Aims:

  1. To evaluate the impact of biochar on crop production at the field scale over multiple cropping cycles
  2. To evaluate the impact of biochar on soil quality at the field scale over multiple cropping cycles
  3. To assess the impact of biochar on ecosystem service delivery
  4. To quantify the impact of repeated biochar doses on crop and soil quality
  5. To evaluate farmer opinion on the use of biochar in cropping systems
  6. To assess the impact of biochar on metal, pesticide and PAH movement and attenuation in soil

Brief description

The trial is located at the Bangor University Henfaes Research Centre in the lowland part of the farm. Mixed hardwood biochar was added in a randomised block design field trial at three rates in 2009 (0, 25 or 50 t ha-1). Biochar application rates above this showed negative plant growth responses in pot trials. There are 4 replicates of each treatment. A map of the field trial is given below.

In year 1 (2009) we grew forage maize while in Year 2 (2010) we laid the field trial into grass. In Year 3 (2011) we ploughed up the grass and planted forage beans. In Year 4 (2012) we planted barley and in Year 5 (2013) we reverted back to forage maize. In 2011, we decided to split the plots and perform a repeat biochar application. This now gives the trial 5 treatments (0, 25, 25+25, 50, 50+50 t ha-1) with four replicates of each treatment. The trial design shown below reflects this. The soil at the site is a fertile Eutric Cambisol. Initially, the crops received fertiliser (2009); however, we are currently in a nutrient rundown period to see what the residual effect of the biochar is (i.e. when fertilisers are not applied). There is a Met station located on site.

We have studies various aspects within this trial including crop growth and yield, weeds, soil biodiversity, pesticide movement, greenhouse gas emissions, soil nutrient effects, microbial colonization of the biochar, nitrogen and carbon dynamics, water dynamics, N-fixation. These have not been measured continuously but in season campaigns aligned to the availability of staff and crop type. Studies need to continue to determine the long term effects. The focus for 2013 will be the study of weed-pesticide interactions, crop yield and soil nutrients. Details of the findings over the last 4 years have been summarised in the publications listed below.

Collaborators

We welcome collaboration on this trial. We can host visits and supply samples for research purposes to interested parties from the UK and overseas. The contact details are listed at the top of the page. Past collaborations include:

Prof Daniel Murphy, University of Western Australia
Dr Daniel Dempster, University of Western Australia
Dr Richard Quilliam, University of Stirling, UK
Dr Johannes Rousk, University of Lund, Sweden

Publications arising from this experiment

Quilliam, RS; DeLuca, TH; Jones, DL (2013) Biochar application reduces nodulation but increases nitrogenase activity in clover. Plant and Soil 366, 83-92.

Quilliam, RS; Rangecroft, S; Emmett, BA; DeLuca TH, Jones DL (2013) Is biochar a source or sink for polycyclic aromatic hydrocarbon (PAH) compounds in agricultural soils? Global Change Biology Bioenergy 5, 96-103.

Quilliam, RS; Marsden, KA; Gertler, C; Rousk, J, DeLuca, TH, Jones DL (2012) Nutrient dynamics, microbial growth and weed emergence in biochar amended soil are influenced by time since application and reapplication rate. Agriculture Ecosystems & Environment 158: 192-199.

Dempster, DN; Jones, DL; Murphy, DV (2012) Organic nitrogen mineralisation in two contrasting agro-ecosystems is unchanged by biochar addition. Soil Biology & Biochemistry 48: 47-50.

Jones, DL; Rousk, J; Edwards-Jones, G; DeLuca TH, Murphy, DV (2012) Biochar-mediated changes in soil quality and plant growth in a three year field trial. Soil Biology & Biochemistry 45: 113-124.

Dempster, DN; Jones, DL; Murphy, DV (2012) Clay and biochar amendments decreased inorganic but not dissolved organic nitrogen leaching in soil. Soil Research 50: 216-221.

Jones, D. L.; Murphy, D. V.; Khalid, M.; Ahmad, A; Edwards-Jones G; DeLuca TH (2011) Short-term biochar-induced increase in soil CO2 release is both biotically and abiotically mediated. Soil Biology & Biochemistry 43: 1723-1731.

Jones, DL; Edwards-Jones, G; Murphy, DV (2011) Biochar mediated alterations in herbicide breakdown and leaching in soil. Soil Biology & Biochemistry 43: 804-813.

Photographs of the trial

Figure 1. The application of biochar to the field plots before being power harrowed into the soil

Figure 2. The biochar field trial site planted with fodder maize

Figure 3. Biochar pieces lying on the surface after incorporation in Year 1 of the trial with maize