Effect of compost and earthworm production on soil properties, growth and dry matter yield of maize in crude oil degraded soil
Journal of Soil Science and Environmental Management 2017
A Nigerian researcher has shown that the addition of compost and worms helps to reclaim soil that has been contaminated with crude oil. The study was done with 4 compost types that were mixtures of cassava compost and/or pig or poultry manure composts. The compost was mixed in with soil at a 1:5 ratio (compost:soil), 10 earthworms were added to each soil blend, and lastly corn seeds were planted in each test soil. The control soil was simply oil degraded soil without compost added. The test was ran for eight weeks. At the end of the experiment, all of the earthworms in the oiled soil were dead. The poultry compost had 7 survive, while the pig compost had an increase of worms to the tune of 36 (that's 26 new worms in 8 weeks!). The corn was also greatly affected by the addition of compost. The shoot and root dry matter of the oil-only soil was some 0.46 grams, while the cassava/poultry/pig compost weighed about 90 grams (the other compost/soil mixes had various results worth checking out in the link to the full article). This research shows that there is hope in saving soils that have been damaged by oil spills. A big thanks to the the single scientist, Nweke I. A., that did all this work.