Towards Horizon 2020 Lasaponara R., Masini N., Biscione M., Editors EARSeL, 2013 Monitoring of surface waters of mountainous Polish river with the use of MONERIS and SWAT models Monika Tomaszewska 1 , Malgorzata Stolarska 2 , Zbigniew Bochenek 1 1 Institute of Geodesy and Cartography, Department of Remote Sensing, Warsaw, Poland; monika.tomaszewska@igik.edu.pl; zbigniew.bochenek@igik.edu.pl 2 University of Lodz, Department of Applied Ecology - malgo100@tlen.pl Abstract. Presented study has been carried out in the ESA PECS Project: “Application of r e- motely sensed data for transboundary water resource management”. The Institute of Geodesy and Cartography developed the method supporting the management of surface waters by integrating Earth Observation using land cover / land use data into specialized water quality and agri- economical models. The method elaborated within the project is based on application of models which enable to estimate pollution of surface waters by nitrogen and phosphorus compounds. Two models were tested: SWAT (Soil and Water Assessment Tool) and MONERIS (Modelling Nutri- ent Emissions in River Systems). The MONERIS model is very popular in Europe and USA but less in Poland. Both models are enriched with numerous thematic layers, considering various as- pects of environment. Land cover / land use map is one of the most valid layers in both models; it is generated using high-resolution satellite images (IRS LISS 4). The experiment was conducted over the Ropa river catchment (974 km2), which is located in the south part of Poland and as a mountainous river, has a high volatility of river flows. In the first step of the project the SWAT model was used, while the second step of the methodology was focused on evaluating water qual- ity based on MONERIS model. Data created by SWAT model about river flows were used as an input data and to enhance the MONERIS model. Analysis of the results obtained through applica- tion of different scenarios, as well as comparison of both models, were presented at final part of the article. Keywords. Water quality, SWAT model, MONERIS model, nutrient emission 1. Introduction Complex management of quality of water resources should be based on reliable evaluation of levels of water pollution and on monitoring their changes. Management systems of water resources aim at assessment of impact of agriculture, environmental conditions and anthropogenic factors on water quality. The main objective is to prepare instructions for implementing programs of sustain- able development, according to Water Framework Directive and related directives. System of water resource management proposed within ESA PECS Project “Application of re- motely sensed data for transboundary water resource management” assumes integration of data, compiled as thematic layers within spatial model. Source data for creating particular layers include remotely sensed information (land cover, vegetation indices) calibrated with in-situ measurements. Next, after feeding model with multi-source data the process of modeling is performed in order to obtain information on type and amount of water pollutants. Two models are applied in the presented study: SWAT (Soil and Water Assessment Tool) and MONERIS (Modelling Nutrient Emmissions in River Systems). Linking of the databases used in both models is an additional asset for creating system of water management. Results of applying SWAT model, related to intensity of river flows, can be used as input data for MONERIS model, enabling to make analyses within this model in a greater spatial detail.