SWAT modelling in the Upper Don River subcatchment

Shared by Russia and Ukraine the basin of the Azov Sea is unique and important ecosystem providing regional population and national economies with numerous ecosystem goods and services (EGS). However, due to unsustainable management the capacity of the Azov ecosystem to maintain these goods and services has decreased significantly. The problem is exacerbated by lack of regional cooperation and continuing degradation of the Azov ecosystem A long-term regional development strategy should be elaborated to secure EGS provision and sustainable development. An essential part of strategy is an assessment of future water availability depending on potential changes in demography, land use and climate conditions.

The assessment of currently available ecosystem goods and services and their future availability is being incorporated as a vital component into policy-making process in last years. Different integrated environmental models are available to analyze data, required for the EGS estimates and for  developing future EGS projections.

The Soil Water Assessment Tool (SWAT) is one of such integrated modelling frameworks. Numerous studies have been conducted applying SWAT for different purposes. SWAT found application both in performing EGS assessment, as a baseline integrated tool and within the complex hydro-economic modelling frameworks. This research provided the case study of the EGS assessment with SWAT in the framework of the EnviroGRIDS project.

The ArcGIS-ArcView extension and graphical user input interface for SWAT ArcSWAT 2009.93.7b has been used for model development and running. For developing SWAT input data different datasets have been used.

Unique hydrologic response units (HRU) have been defined based on defining and combination of classes of land use, soil and slope. Reclassified MODIS land cover datasets, developed by EnviroGRIDS project for Metronamica model has been used for land use data input. Global soil dataset FAO has been used for soil data input. The data for the period 1998-2008 for 5 stations have been used for simulating meteorological parameters in the model.

The SWAT-CUP application has been applied for model calibration and validation. For this purpose observed monthly data on the water discharge for 9 outlets, matching existing hydrological gages, covering period 2001-2008, have been used.

The scenarios on land use and climate change developed by EnviroGRIDS project, using data for 2050 have been formulated and anlyzed with developed SWAT model. Corresponding change of water inflow into Tsimlyansk reservoir has been analyzed, recommendations for desicion-makers have need developed.