Providing evidence to improve practice

Action: Amend the soil with municipal wastes or their composts Soil Fertility

Key messages

Two controlled, replicated trials in Spain and the United Kingdom measured the effect of adding wastes to the soil. One trial found that adding municipal compost to semi-arid soils greatly reduced soil loss and water runoff. One found mixed results of adding composts and wastes.

SOIL TYPES COVERED: coarse loamy, sandy loam.

Supporting evidence from individual studies

1 

A controlled, replicated experiment in 2000 on a semi-arid, coarse loamy soil in Alcantarilla, Spain (Ros et al. 2001) found that adding composted municipal waste was the most effective of three soil amendments, reducing soil loss by 94% and water runoff by 54% compared to an untreated control. Unstabilized municipal waste and sewage sludge reduced soil loss by 78% and 80% (respectively) and increased the soil’s ability to hold water by 43% and 24%. There were four treatments: an untreated control, municipal waste compost, an unstabilized municipal waste and sewage sludge. Treatments were tested in plots of 10 x 3 m and replicated three times. Stability of aggregated soil particles was measured and a runoff collector was installed downslope of each plot.

 

2 

A replicated, controlled study in 2000 on sandy loam soil in Wellesbourne, United Kingdom (Rahn et al. 2009) found that adding sugar beet Beta vulgaris tops with compost to a barley Hordeum vulgare crop increased soil mineral nitrogen by 11 kg/ha and yield by 11% , compared to no addition. Adding paper waste with sugar beet tops did not affect soil mineral nitrogen but improved yield by 23%. Adding sugar beet tops with straw, compactor waste or double rates of compactor waste reduced soil mineral nitrogen by 25, 15 and 36 kg/ha, and reduced yield by 47%, 21% and 63%, respectively. Amendments were applied at 3.2-3.8 t/ha, including compactor (machine which compresses waste material to reduce the space it takes up) and paper waste from the recycling industry, recently-harvested wheat Triticum aestivum straw, compost from municipal green waste, and liquid molasses (thick brown, uncrystallized juice from raw sugar) from the sugar refining industry. Amendments were applied with 42 t/ha sugar beet tops.

 

Referenced papers

Please cite as:

Key, G., Whitfield, M., Dicks, L.V., Sutherland, W.J. & Bardgett, R.D. (2017) Enhancing Soil Fertility. Pages 383-404 in: W.J. Sutherland, L.V. Dicks, N. Ockendon & R.K. Smith (eds) What Works in Conservation 2017. Open Book Publishers, Cambridge, UK.