Phosphorus Leaching From Naturally Structured Forest Soils Is More Affected by Soil Properties Than by Drying and Rewetting

Foliar phosphorus (P) concentrations in beech trees are decreasing Europe, potentially leading to reductions the trees’ growth and vitality. In course of climate change, drying rewetting (DRW) cycles forest soils expected intensify. As a consequence, P leakage from root zone may increase due temporarily enhanced organic matter mineralization. We addressed questions whether sites with different soil properties, including pools, differ their susceptibility DRW-induced leaching, this is affected by DRW intensity. A greenhouse experiment was conducted on naturally structured columns saplings three representing gradient availability. Four were air-drying irrigating over 4 hours (fast rewetting) or 48 (slow rewetting). Leachates below analyzed for total P, molybdate reactive (considered as inorganic P). The difference considered represent organically bound P. Boosted regression used examine effects characteristics leaching. Contrary first hypothesis, that leaching increases upon intensity preceding desiccation phase, intense (to pF 3.5 4.5) did not generally compared moderate 2 3). However, we observed increased decreased leachates after matric potentials above 4. Also against our expectations, fast lead higher than slow rewetting. results confirmed third hypothesis site poorest where recycling mainly limited humus layer uppermost mineral soil, lost considerably more during other two sites. imply intensified cycles, predicted climate-change scenarios, per se soils. Soil properties such carbon content texture appear be important predictors losses.