@article{HesseKrysanovaVetteretal.2013, author = {Hesse, Cornelia and Krysanova, Valentina and Vetter, Tobias and Reinhardt, Julia}, title = {Comparison of several approaches representing terrestrial and in-stream nutrient retention and decomposition in watershed modelling}, series = {Ecological modelling : international journal on ecological modelling and engineering and systems ecolog}, volume = {269}, journal = {Ecological modelling : international journal on ecological modelling and engineering and systems ecolog}, number = {34}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0304-3800}, doi = {10.1016/j.ecolmodel.2013.08.017}, pages = {70 -- 85}, year = {2013}, abstract = {Retention and transformation of nutrients within a river catchment are important mechanisms influencing water quality measured at the watershed outlet. Nutrient storage and reduction can occur in soils as well as in the river and should be considered in water quality modelling. Consideration is possible using various methods at several points during modelling cascade. The study compares the effects of five different equation sets implemented into the Soil and Water Integrated Model (SWIM), one describing terrestrial and four in-stream retention with a rising complexity (including algal growth and death at the highest complexity level). The influences of the different methods alone and in combinations on water quality model outputs (NO3-N, NH4-N, PO4-P) were analyzed for the outlet of the large-scale Saale basin in Germany. Experiments revealed that nutrient forms coming primarily from diffuse sources are mostly influenced by retention processes in the soils of the catchment, and river processes are less important. Nutrients introduced to the river mainly by point sources are more subject to retention by in-stream processes, but both nutrient retention and transformation processes in soils and rivers have to be included. Although the best overall results could be achieved at the highest complexity level, the calibration efforts for this case are extremely high, and only minor improvements of overall model performance with the highest complexity were detected. Therefore, it could be reasoned that for some research questions also less complex model approaches would be sufficient, which could help to reduce unnecessary complexity and diminish high uncertainty in water quality modelling at the catchment scale. (C) 2013 Elsevier B.V. All rights reserved.}, language = {en} } @article{DidovetsLobanovaBronstertetal.2017, author = {Didovets, Iulii and Lobanova, Anastasia and Bronstert, Axel and Snizhko, Sergiy and Maule, Cathrine Fox and Krysanova, Valentina}, title = {Assessment of Climate Change Impacts on Water Resources in Three Representative Ukrainian Catchments Using Eco-Hydrological Modelling}, series = {Water}, volume = {9}, journal = {Water}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2073-4441}, doi = {10.3390/w9030204}, pages = {18}, year = {2017}, abstract = {The information about climate change impact on river discharge is vitally important for planning adaptation measures. The future changes can affect different water-related sectors. The main goal of this study was to investigate the potential water resource changes in Ukraine, focusing on three mesoscale river catchments (Teteriv, UpperWestern Bug, and Samara) characteristic for different geographical zones. The catchment scale watershed model—Soil and Water Integrated Model (SWIM)—was setup, calibrated, and validated for the three catchments under consideration. A set of seven GCM-RCM (General Circulation Model-Regional Climate Model) coupled climate scenarios corresponding to RCPs (Representative Concentration Pathways) 4.5 and 8.5 were used to drive the hydrological catchment model. The climate projections, used in the study, were considered as three combinations of low, intermediate, and high end scenarios. Our results indicate the shifts in the seasonal distribution of runoff in all three catchments. The spring high flow occurs earlier as a result of temperature increases and earlier snowmelt. The fairly robust trend is an increase in river discharge in the winter season, and most of the scenarios show a potential decrease in river discharge in the spring.}, language = {en} } @article{DidovetsKrysanovaBuergeretal.2019, author = {Didovets, Iulii and Krysanova, Valentina and B{\"u}rger, Gerd and Snizhko, Sergiy and Balabukh, Vira and Bronstert, Axel}, title = {Climate change impact on regional floods in the Carpathian region}, series = {Journal of hydrology : Regional studies}, volume = {22}, journal = {Journal of hydrology : Regional studies}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2214-5818}, doi = {10.1016/j.ejrh.2019.01.002}, pages = {14}, year = {2019}, abstract = {Study region: Tisza and Prut catchments, originating on the slopes of the Carpathian mountains. Study focus: The study reported here investigates (i) climate change impacts on flood risk in the region, and (ii) uncertainty related to hydrological modelling, downscaling techniques and climate projections. The climate projections used in the study were derived from five GCMs, downscaled either dynamically with RCMs or with the statistical downscaling model XDS. The resulting climate change scenarios were applied to drive the eco-hydrological model SWIM, which was calibrated and validated for the catchments in advance using observed climate and hydrological data. The changes in the 30-year flood hazards and 98 and 95 percentiles of discharge were evaluated for the far future period (2071-2100) in comparison with the reference period (1981-2010). New hydrological insights for the region: The majority of model outputs under RCP 4.5 show a small to strong increase of the 30-year flood level in the Tisza ranging from 4.5\% to 62\%, and moderate increase in the Prut ranging from 11\% to 22\%. The impact results under RCP 8.5 are more uncertain with changes in both directions due to high uncertainties in GCM-RCM climate projections, downscaling methods and the low density of available climate stations.}, language = {en} }