Soil silicon: Plant-availability and biotic solubilisation in hotspots of nutrient turnover
Abstract
While many plants strongly accumulate silicon (Si) in their biomass, Si is no essential nutrient for most plants, but is beneficial in alleviating environmental stresses (plant diseases, herbivory, drought, metal toxicity). After Si uptake and translocation to the plant shoot, it is concentrated and precipitated in the leaves due to transpiration, forming amorphous SiO2 bodies (phytoliths). These phytoliths are returned to the soil in plant litter and harvest residues, and are, together with amorphous SiO2 precipitated from the soil porewater, the main bioavailable Si fraction in soil. By exporting phytoliths from the field to-gether with the crop and harvest residues (straw), and by increased erosion rates, agriculture has a strong impact on plant-available soil Si and the terrestrial Si cycle. Although there is currently a strong research focus on soil Si dynamics (e.g. global biogeochemical Si cycling, agricultural impact on bioavailable soil Si), many aspects of plant-soil Si interactions are not well understood. This applies particularly to the Si biogeochemistry of soils of the temperate region, and to the impact of biota, such as plant roots and earthworms, on labile soil Si fractions and soil Si solubilisation. There is a strong need for closing these knowledge gaps in order to avoid decreases in crop yields and quality, to enhance the sustainability of agricultural production in future, and to close the terrestrial and global Si cycles. Therefore this project aims (1) at using innovative infinite sink extraction methods combined with elemental and isotopic fingerprinting for quantifying plant-available Si pools and their mineral origin, (2) and at studying the effects of root exudates and (3) earthworms on soil Si solubilisation and plant-availability.
rhizosphere earthworm biogeochemistry phytolith soil ecology
Publikationen
Project staff
Jakob Santner
Priv.-Doz. Dipl.-Ing. Dr.nat.techn. Jakob Santner
jakob.santner@boku.ac.at
Project Leader
01.11.2019 - 31.07.2023
Markus Puschenreiter
Priv.-Doz. Dr. Markus Puschenreiter
markus.puschenreiter@boku.ac.at
Tel: +43 1 47654-91143, 91163
Project Staff
01.11.2019 - 31.07.2023
Walter Wenzel
Univ.Prof. Dipl.-Ing. Dr.nat.techn. Walter Wenzel
walter.wenzel@boku.ac.at
Tel: +43 1 47654-91143, 91161
Project Staff
01.11.2019 - 31.07.2023
Johann Zaller
Assoc. Prof. Dr. Johann Zaller
johann.zaller@boku.ac.at
Tel: +43 1 47654-83318
Project Staff
01.11.2019 - 31.07.2023