Vízügyi Közlemények, 1999 (81. évfolyam)

3. füzet - Jolánkai G.-Bíró I.: földrajzi információs rendszeren alapuló integrált vízgyűjtő modell fejlesztés és alkalmazás a Zala-vízgyűjtőre

480 Jolánkai G. -Bíró I. the team, consisting of researchers of the Institute of Hydrology (UK) and the University of Utrecht (NL) for submitting a tender to the Environment and Climate Programme of the European Union. The project objective was the development of catchment models that can be used for supporting water and environmental managemnt decisions by predicting the changes of the quality and quantity of water resources under changing climate, environmental and economic conditions. The model was to be calibrated and validated on data from pilot catchments in the UK and Hungary. The Hungarain Pilot catchment was the Zala River Basin (Figure 1.). The activities of the Project were carried out in team work, with a large number of participants. The participants are listed in the footnote of the first page and their work is referred to in the reference list. The work was carried out in seven "work packages" in both the Hungarian and the UK catchments: i.) Assessment of the impact of climate changes on surface water quantity and quality. ii.) Development of a Geographical Information System (GIS) and monitoring database for the pilot catchments. iii.) Development and adaptation of an integrated catchment model of hydrological and water quality processes. iv.) Identification of important issues of water and environmental management, in relation to climate changes and the anthropogenic context. v.) Identification of control strategies aimed at resolving issues identified in (iv). vi.) Testing the effectiveness of long-term and short-term action programmes and control scenarios using the models' predictive capabilities. vii.) Elaboration of proposals for the application of the system for other catchments. In developing the geographical information system the following digital maps have been utilized (Figure 2.): — Digital maps (of 200 mx200 m resolution) of the terrain (DTM); — Land use map (Corine) of the terrain (DTM); — Soil map "Agrotopo" of the area; — The fertilizer usage map of the catchment was generated on the basis of detailed surveys, data collection and measurements by Dr. I. Sisák (1995) in the period 1985—87; — The phosphorus budget map of the soils of the farming units of the catchment, also based on the work of Sisák (1995); Model development was made in two directions: — The frst was the further development of the model system SENSMOD (Jolánkai, 1986; Jolánkai et al, 1993; Jolánkai, 1991 ; Jolánkai, 1992). Development objectives included the refinement of the spatially distributed features and capabilities of the model, to better suit GIS application and to make better use of digitized maps. The second was to improve the hydrological sub-model in order to improve runoff modelling and to put the runoff-material export calculations to a sounder basis. The third objective was to create a reservoir sub-model for water quality (phosphorus retention) due to the presence of many reservoirs in the river basin. — The second group of development activities was directed on the development of a simulation model of reservoir operation in order to be able to numerically express and analyze the impacts of p(R)tential climate changes, that is water shortages if any, and analyze the effects of counter action. The authors stated stated that the principles and equations of the resérvoir were developed by another team (Gilyénné-Hofer A., 1998) and the authors of this study were contributing only to the computer implementation and made the analysis. Results of the analysis of natural changes and control strategies (scenariosj with the model SENSMOD were as follows: Natural conditions, the variation of runoff, were considered in three scenarios: Rl- the multiannual mean runoff, R2- the recorded highest annual runoff and R2a-the annual runoff correspond-