The role of organic amendments in soil reclamation: A review

Abstract

Larney, F. J. and Angers, D. A. 2012. The role of organic amendments in soil reclamation: A review. Can. J. Soil Sci. 92: 19–38. A basic tenet of sustainable soil management is that current human activities are not detrimental to future generations. Soils are degraded by natural events (erosion) or industrial activity. A prevalent feature of degraded or disturbed soils is lack of organic matter compared with adjacent undisturbed areas. Organic amendments, such as livestock manure, biosolids, pulp and paper mill by-products, wood residuals and crop residues, are produced in abundance in Canada and could be widely used in soil reclamation. Biosolids production is ∼0.5 Tg yr−1(dry wt.); paper mill sludge generated in the province of Quebec was ∼2 Tg (wet wt.) in 2002. This review paper examines mechanisms through which organic amendments affect soil properties (physical, chemical, biological) and describes the role of organic amendments in reclamation, with emphasis on amendment types and application rates for soil amelioration and biomass production. Single large applications of organic amendments can accelerate initial reclamation and lead to self-sustaining net primary productivity. Readily decomposable organic amendments may provide immediate, but transient, effects, whereas stable, less decomposable materials may provide longer-lasting effects. Using organic amendments for reclamation is mutually beneficial wherein waste products from agriculture, forestry and urban areas help other sectors meet their land reclamation goals.