Soil organic matter and structural stability: mechanisms and implications for management

  title={Soil organic matter and structural stability: mechanisms and implications for management},
  author={J. Malcolm Oades},
  journal={Plant and Soil},
SummaryThe stability of pores and particles is essential for optimum growth of plants. Two categories of aggregates macro- (> 250 μm) and micro- (<250 μm) depend on organic matter for stability against disruptive forces caused by rapid wetting. Dispersion of clay particles from microaggregates is promoted by adsorption of complexing organic acids which increase the negative charge on clays. The acids are produced by plants, bacteria and fungi. However, the dispersibility of clay in… 

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