University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Robert Manglberger
(2018):
An assessment of soil P extractability and plant P availability for a resin-based (DGT) and batch extraction methods.
Master / Diploma Thesis - Institut für Bodenforschung (IBF),
BOKU-Universität für Bodenkultur,
pp 45.
UB BOKU
obvsg
FullText
- Abstract:
- To improve the determination of plant available phosphorus in agricultural soils and the derived fertilizer recommendations, the establishment of a new sampling method is highly required. This work attempted to clarify if the diffusive gradients in thin films technique (DGT) is a suitable means to predict plant available P in a wide range of soils. Another aim was to unravel the influence of certain soil characteristics on the extractability of P with the use of the DGT technique in comparison to conventional extraction techniques. Therefore, 41 Austrian soil samples covering a large variety of soil types and P concentrations were investigated with the following methods: Diffusive gradients in thin films (DGT), Soil porewater concentration, Calcium acetate lactate (CAL), Water extraction (H2O), Sodium bicarbonate (Olsen), Mehlich 3, Electro-Ultrafiltration (EUF), Acid Ammonium Oxalate in Darkness (AAO), Sodium Citrate-Bicarbonate-Dithionite (CBD), Total P (aqua regia). While it was not productive to compare the amount of phosphorus extracted by the various methods, correlations of varying degrees were found between them. DGT displayed a strong relatedness not only with the other weak extraction methods but also with some of the stronger ones. Significant correlations with all soil P tests except CAL could be observed for the soil parameters pH, texture and Total P content which indicated a strong influence of these factors on the general P extractability. A plant experiment was conducted in order to compare the correlation between the established methods and DGT with regard to plant P uptake. The results did not indicate a clear superiority of DGT over the other techniques as had been reported previously by various other authors. The performance of DGT appeared to be strongly dependent on certain soil characteristics, especially on the P sorption capacity. However, it proved to be a solid method that can be used over a wide range of soils.
- Beurteilende(r): Puschenreiter Markus
- 1.Mitwirkender: Santner Jakob