| Abstract: | Organic matter and wetting properties of soil samples — an interpretation Samples were taken from A horizons of Udands and Humults at four 4 sites under forest and pasture vegetation in Southern Chile. Aggregates of 4—6 and 10—12 mm diameter were obtained by sieving and separated into aggregate surface and core fraction by peeling. The fraction 38—63 μm was separated by sieving. Organic matter was determined in all samples. Wetting angles were determined by direct reading at drops of saturated KCl solution on a layer of particles fixed on microscope glass slides by double‐sided adhesive tape. Values were correlated with contents of organic matter. The results showed an increase of wetting angles with increasing percentage of organic matter in the overall samples as well as in all separate groups (depth, vegetation, size, and parts of aggregates). The correlations, however, were not close (r ～ 0.5), irrespective of the significance level. Wetting angles in soils are caused by combined effect of different relative amounts and properties of free organic matter particles and organic films on mineral particles. |
