Gewählte Master / Diploma Thesis:
Christine Weissensteiner
(2014):
Phosphorpools und Phosphorbilanzen im österreichischen Dauergrünland.
Master / Diploma Thesis - Institut für Ökologischer Landbau (IFÖL),
BOKU-Universität für Bodenkultur,
pp 156.
UB BOKU
obvsg
Data Source: ZID Abstracts
- Abstract:
- In Austria, the CAL-soluble phosphorus (PCAL) is considered as plant-available and therefore used for fertilizer recommendations. Most of the studied grassland soils in Austria are characterized by low contents of PCAL. Furthermore, there is a lack of published investigations about other P-fractions.
Therefore the relationship between the PCAL in soil and the P-content as well as P-removal in plants was examined. Moreover, soil samples were investigated with regard to their P-fractions and factors influencing them. In addition, exemplary nutrient budgets were calculated.
In terrestrial soils the PCAL was a measure for the ability of the soil to supply P. In order to get a suitable PCAL-value it is crucial to take multiple soil samples under comparable conditions. Furthermore, not only the P-level in the soil, but also the intensity of management influenced the P-contents in the plants and consequently the P-removal.
Although a high percentage of the investigated soils (0 to 10 cm) showed low levels of PCAL, high total P contents could be detected. Therefore, in grassland soils, the main problem seems to be mobilization. The organic P-fraction was frequently the most important P-pool. The investigated soils usually exhibited high phosphorus sorption capacities and the degree of phosphorus saturation was low. Important factors influencing the P-fractions were the intensity of management, soil type, pH-value, clay- & organic carbon content and the content of sesquioxides.
Grassland farms are not generally characterized by negative budgets (P). The most important factors are the demand of external fodder and straw as well as the achievable output.
For a site adapted fertilizer recommendation a variety of instruments should be used (e. g. nutrient balance, soil analysis (PCAL, total P, plant species composition).
-
Beurteilende(r):
Friedel Jürgen Kurt
-
1.Mitwirkender: