RESTORATION OF SOIL FUNCTION REQUIRES PLANTS, ARBUSCULAR MYCORRHIZAL FUNGI AND ORGANIC MATTER

Yıl 2010, Cilt: 25 Sayı: 1, 16 - 19, 20.08.2010

C.n. Daynes D.j. Fıeld J.a. Saleeba M.a. Cole P.a. Mcgee

Öz

The hierarchical model of aggregation proposes that soil aggregation is due to a stepwise hierarchy of processes. The model is normally experimentally tested using topsoil by disrupting and dispersing aggregates and characterising the end products, that is, a top down approach. We present a series of experiments testing the model using a resilience approach, attempting to create an aggregated soil by adding the required constituents to a massive soil, a bottom up approach. Plants, with or without 8 arbuscular mycorrhizal fungi were grown for 6 months in sieved mine spoil amended with up to 18% organic matter. The soils were examined for aggregation, water holding capacity and carbon content. The data broadly support the hierarchical model. Maximisation of functional complexity as indicated by water retention curves and particle mean weight diameter required approximately 12% organic matter (3% organic carbon), plants and the presence of AM fungi. We conclude that successful remediation of a massive soil requires consideration of the complexity of the interaction between plant, AM fungus and organic matter, and that the hierarchical model of aggregation serves as a useful tool in soil restoration.

Anahtar Kelimeler

Carbon, Hierarchical model, Mean weight diameter, Soil aggregate, Water retention

FU GI A D ORGA IC MATTER

Öz