Model system STOFFBILANZ

Users and application areas

The modelling of soil erosion by water as well as sediment, nitrogen and phosphorus inputs in river basins was carried out as part of various projects funded by the federal and state governments (e.g. Saxony, Baden-Württemberg, Saxony-Anhalt, Rhineland-Palatinate, Lower Saxony), associations, dam administrations and research institutions. In this context, the STOFFBILANZ model was developed and successfully applied, optimised and further developed in many areas of Central Europe and now also in Asia and Africa.

Fields of application

In Germany, STOFFBILANZ is primarily used in connection with the implementation of the EU Water Framework Directive (WFD), the Fertiliser Ordinance and the obligations to achieve marine protection targets. The model results on nitrogen and phosphorus inputs can be used to derive the need for reductions in order to achieve environmental quality targets and fulfil environmental quality standards. Scenario calculations are used to analyse the potential impact of measures to reduce substance inputs. The focus here is on measures in the area of urban water management and agri-environmental measures in agriculture.

What is STOFFBILANZ capable of?

Modelling with STOFFBILANZ includes soil erosion by water as well as sediment, nitrogen and phosphorus inputs. The main input sources and pathways are identified and calculated for each natural area and utilisation. The results represent spatially differentiated orders of magnitude of the substance inputs. As a balance model, STOFFBILANZ basically allows statements to be made on steady-state conditions for long-term observation periods. However, the ongoing development of the model and links with other process-orientated models (water balance - KLIWES and humus balance - CCB) have now enabled calculations to be made in annual increments. Depending on the data situation and project requirements, day-based approaches (USLEM, FAO evaporation, surface runoff, etc.) can also be used or integrated.The improvement of the data situation with regard to digital elevation models and precipitation data as well as the rapid developments in high performance computing now enable us to calculate with very small grid resolutions. Modelling with 1m resolution has already been carried out at federal state level and nationwide with 10m resolution.The STOFFBILANZ modelling system is structured in such a way that the water, nitrogen and phosphorus balance can be calculated comprehensively with varying data. As the system has a modular structure, individual approaches or even complete modules (e.g. groundwater pathway) can be replaced by coupling with other models (MODFLOW). STOFFBILANZ can also be used to calculate individual modules (e.g. soil erosion) for other modelling networks. Our many years of project experience have shown that cooperation and exchange with other modelling groups have a positive effect on the project results.

Milestones

Important milestones in the development of the model:

2024

Integration of the STOFFBILANZ viewer in new landing page, integration of Django framework, containerisation with Docker, load balancer for load distribution

Integration of the raster export into the STOFFBILANZ Viewer web application

Use of model concept for modelling high-resolution sediment transfers (1 m) in Baden-Württemberg with the METRIS model (KIT/LUBW)

2023

Use of OpenCV to calculate high-resolution spatial algorithms (e.g. shading, wind erosion)

2022

Assessment of the need to reduce phosphorus inputs from urban water management in Saxony

Automation of data integration into the STOFFBILANZ model

2020

Humus turnover and nitrogen inputs into water bodies - coupling with the CCB model

2019

Use of the model concept for modelling high-resolution sediment transfers (10 m) in Germany with the MoRE-DE approach (KIT/UBA)

Integration of binary data storage in the hdf5 (Hierarchical Data Format) raster format as a basis for modelling and visualisation.

Update of the viewer interface (front end) to improve the user logic and simplify operation, design adjustments according to 'state of the art'.

2015

The software integration of a matrix calculator now allows the processing of very large amounts of data in modelling with STOFFBILANZ.

2013

Provision of the web-based portal STOFFBILANZ Viewer for the BMBF-funded project ‘SPACES - SGD’ (South Africa).

2012

Technological reorganisation of the web-based STOFFBILANZ viewer.

Realisation of a day-based resolution of the modelling of water flows, soil erosion, sediment input and particle-bound P input as part of the BMBF-funded project 'Development and implementation of a scientifically based management system for the reduction of diffuse substance inputs into the Miyun drinking water reservoir near Beijing' (FKZ 02WM1049).

2011

Integration of potential measures to reduce soil erosion and material input for the whole of Saxony on behalf of the LfULG

2010

In the 'Biomass' research project of the LfULG Saxony, the model is used to analyse the effects of increasing cultivation of renewable raw materials on the water balance and water protection based on scenarios.

2009

The retention of N takes into account the N uptake rate from the sediment and the residence time of the water (Nutrient Spiralling concept). Retention in still waters/reservoirs is carried out separately.

The average annual amount of P retained in the floodplain of watercourses is calculated from the amount of sediment deposited and the specific particulate-bound P concentration in the sediment.

Consideration of groundwater residence times in the unconsolidated rock area by modelling the velocities and flow paths in the upper aquifer using a multiple-flow approach.

Comprehensive use and further development of the STOFFBILANZ_Logar modelling approach in the Upper Rhine Graben as part of the EU project 'LOGAR' (responsible LUBW Karlsruhe, LTZ Augustenberg, Region Alsace, Agence de l'eau Rhin-Meuse, DIREN Alsace, BRGM).

2008

Activation of the WebGIS-based STOFFBILANZ viewer.

Mapping of dissolved N loads with improved inclusion of mobilisation and immobilisation.

2007

Initiation of the research project 'Nutrient Atlas Saxony' on behalf of the LfULG.

Development of the model 'STOFFBILANZ_BW', modified for the conditions in Baden-Württemberg, for modelling the N-inputs into the endangered groundwater bodies of BW in the context of the implementation of the EU Water Framework Directive (WFD) (in cooperation with LTZ Augustenberg).

2006

Further development of the particle-bound input pathway by including the connection probability of erosive surfaces to the water network (DFG project GR 1432/5).

Modelling with STOFFBILANZ in the EU project 'MoNit' for the quantification of nitrate inputs in the Upper Rhine Graben area as a partial model in a nested approach.