Soils developing on sand dunes may have a relatively low capacity to adsorb dissolved organic nutrients and thus retain them in the rooting zone. Our objective was to measure changes during soil development and weathering in the adsorption capacities of soils in the Indiana Sand Dunes chronosequence for dissolved organic C, N, and P. We also determined soil properties that correlated with these changes. Adsorption capacities increased somewhat below the A horizon as soils weathered but they remained low compared to other mineral soils. Soil organic C was inversely related to adsorption capacity. While oxalate extractable Al and Fe tended to increase in the soils with age, extractable Al and Fe were did not correlate well with adsorption capacity probably because a large portion was organically bound (pyrophosphate extractable). This suggests that adsorbing materials tended to became saturated with C a fast as they formed during weathering. This failure to develop a strong adsorption capacity was important in allowing high rates of leaching of dissolved organic N and P even in the oldest soils.
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