Add charcoal to soil before seeding/planting

Overall effectiveness category Evidence not assessed
Number of studies: 1
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How is the evidence assessed?

Effectiveness

not assessed
Certainty

not assessed
Harms

not assessed

Calculating overall effectiveness category

Background information and definitions

Charcoal can be added to soil to increase its fertility, carbon storage, and water retention. When charcoal is used for soil amendment it is commonly known as biochar. Charcoal has a long history of use as a fertilizer, and was used by pre-Colombian Amazonians to enhance soil productivity. Adding charcoal to soil can increase crop yield in agricultural systems (Jeffery et al. 2011), and so addition of charcoal to soil alongside seeding in grasslands may help to increase survival and growth of grassland plants.

The studies detailed in this intervention are direct tests of the effectiveness of adding charcoal to the soil before seeding or planting (e.g. by comparison with an untreated but seeded or planted plot). Studies that represent comparisons of seeding to unseeded plots can be found in the actions ‘Sow grass seeds’, ‘Sow grassland forb species’ or ‘Sow native grass and forbs’.

_{Jeffery, S., Verheijen, F.G., van der Velde, M. & Bastos, A.C. (2011) A quantitative review of the effects of biochar application to soils on crop productivity using meta-analysis. Agriculture, ecosystems & environment, 144, 175–187.}

Study locations

Key messages

One study examined the effects of adding charcoal to soil before seeding/planting on grassland vegetation. The study was in the Netherlands.

VEGETATION COMMUNITY (0 STUDIES)

VEGETATION ABUNDANCE (1 STUDY)

Overall abundance (1 study): One replicated, randomized, paired, controlled study in the Netherlands found that adding charcoal to soil before sowing seeds did not alter overall plant biomass.
Grass abundance (1 study): One replicated, randomized, paired, controlled study in the Netherlands found that adding charcoal to soil before sowing seeds did not alter grass cover.
Forb abundance (1 study): One replicated, randomized, paired, controlled study in the Netherlands found that adding charcoal to soil before sowing seeds increased the cover of legumes but did not alter the cover of other forbs.

VEGETATION STRUCTURE (0 STUDIES)

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

A replicated, randomized, paired, controlled study in 2011 in a restored grassland in the Netherlands (Van de Voorde et al. 2014) found that addition of charcoal to soil before sowing seeds increased the cover of legumes, but did not alter the cover of grasses or other forbs or total plant biomass. Plots where charcoal was added to soil before sowing had higher cover of legumes (39%–41%) than those where no charcoal was added before sowing (14%). However, there was no significant effect of charcoal addition on cover of other forbs (charcoal: 86–90%; untreated: 93%), cover of grasses (charcoal: 6%; untreated: 8%), or total plant biomass (charcoal: 486–495 g/m²; untreated: 465 g/m²). In April 2011, six 4 x 4 m plots were treated with charcoal, produced from grass cuttings heated to either 400°C or 600°C, at a rate of 10 Mg/ha. Plots were paired with untreated plots. All plots were then rotovated and sown with a grassland seed mixture. In August 2011, vegetation cover was assessed in four 1 x 1 m quadrats/plot. In October 2011, vegetation was clipped in two 0.5 x 1 m quadrats/plot to determine plant biomass.
Study and other actions tested
Referenced paper
Van de Voorde T.F., Bezemer T.M., Van Groenigen J.W., Jeffrey S. & Mommer L. (2014) Soil biochar amendment in a nature restoration area: effects on plant productivity and community composition. Ecological Applications, 24, 1167-1177.

Please cite as:

Martin, P.A., Ockendon, N., Berthinussen, A, Smith, R.K. and Sutherland W.J. (2021) Grassland Conservation: Global evidence for the effects of selected interventions. Conservation Evidence Series Synopses. University of Cambridge, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

This Action forms part of the Action Synopsis:

Grassland Conservation

Related Actions

Actions	Effectiveness	Studies	Category
Sow or plant nurse plants (alongside seeding/planting of grassland species) Action Link	Evidence not assessed	4	Synopsis Link
Mow before or after seeding/planting Action Link	Evidence not assessed	10	Synopsis Link
Add woody debris to protect seeds/plants Action Link	Evidence not assessed	1	Synopsis Link