Sammanfattning av doktoranduppgiften
Modelling of phosphorus storage and mobilisation in Swedish agricultural soils
Predictions of P-losses from Swedish agricultural land is today calculated with the computer model ICECREAM, both for scientific purposes and as a part of national environmental assessment activities. With ICECREAM it is possible to calculate P losses from different management scenarios and these results is primarily used as background information for decisions concerning different action plans to reduce the phosphorus load from the Swedish agriculture. There is however a need to adjust the model description to better describe/represent the conditions for P-dynamics in Swedish soils. The model description for P-dynamics is currently based on American analytical methods and soil properties, with some adjustment for Finnish conditions. In this post graduate project a new model formulation for the dynamics of mineral P will be develop to be based on Swedish analytical methods (P-AL, P-HCl) and other soil chemical characteristics. By adapting the description of P-dynamics to Swedish standards there will also be more available data for parameterisation and validation of the model for Swedish conditions. The aim of this post-graduate project is to develop a new model for the dynamics (storage and mobilisation) in short and long time perspectives of the soil mineral P-pools. The project is based on the following sub-projects: 1. Establishing of pedotransfer functions to estimate different P-fractions in soils 2. Development of a new sub-model for the soil mineral P-pools and the dynamics between these pools, including calibration and testing of the new model against measured data. 3. Application of the new model either on a lysimeter or a field experiment to simulate the P-dynamics and leaching losses of dissolved P.