Publication Details

Category Text Publication
Reference Category Journals
DOI 10.3389/ffgc.2020.00094
Licence creative commons licence
Title (Primary) Goethite-bound phosphorus in an acidic subsoil is not available to beech (Fagus sylvatica L.)
Author Klotzbücher, A.; Schunck, F.; Klotzbücher, T.; Kaiser, K.; Glaser, B.; Spohn, M.; Widdig, M.; Mikutta, R.
Source Titel Frontiers in Forests and Global Change
Year 2020
Department OEKOTOX; BOOEK
Volume 3
Page From art. 94
Language englisch
Topic T9 Healthy Planet
Keywords Lüss forest; mesocosm experiment; goethite-P-association; orthophosphate; P recycling system; phosphorus nutrition; plant-available phosphorus; phytate
Abstract In forests, where the supply of bioavailable phosphorus (P) from easily weatherable primary minerals is small, plants are thought to recycle P efficiently by uptake of P released from decomposing forest floor material. Yet a share of the P is leached into the subsoil, where it is strongly adsorbed onto the reactive surfaces of pedogenic Fe and Al oxides. This raises the question of whether P leached into subsoil is also recycled. To investigate the mobilization of P bound to hydrous Fe oxides, we conducted a mesocosm experiment in a greenhouse. Beech saplings were grown for 14 months in subsoil material (Bw horizon from the P-poor Lüss beech forest) with added goethite-P adsorption complexes, in either inorganic (orthophosphate) or organic (phytate) form. Four types of control mesocosms were run: soil only and soil mixed with either dissolved orthophosphate or dissolved phytate or goethite. At the end of the experiment, neither total P mass in trees nor P contents in leaves differed between the treatments. According to leaf nutrient contents, plant growth was strongly limited by P in all treatments. Yet total P mass in trees did not increase over the course of the experiment. Thus, despite its P demand, beech was not able to acquire P from goethite surfaces within two vegetation periods. Also P added in dissolved form to the soil before transplanting as well as native soil P were not available. This suggests that, once inorganic and organic P is bound to pedogenic metal oxides in mineral soil, it is not or hardly recycled, which can be an explanation for field data demonstrating quantitatively significant stocks of P in the subsoil of P-deficient forests.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=26711
Klotzbücher, A., Schunck, F., Klotzbücher, T., Kaiser, K., Glaser, B., Spohn, M., Widdig, M., Mikutta, R. (2020):
Goethite-bound phosphorus in an acidic subsoil is not available to beech (Fagus sylvatica L.)
Front. For. Glob. Change 3 , art. 94 10.3389/ffgc.2020.00094