Observed and predicted changes in the water balance of the Czech landscape– facts and some consequences

0480874 - ÚVGZ 2018 CZ eng A - Abstrakt
Trnka, Miroslav - Vizina, A. - Hanel, M. - Balek, Jan - Hlavinka, Petr - Semerádová, Daniela - Možný, M. - Chuchma, F. - Farda, Aleš - Skalák, Petr - Brázdil, Rudolf - Dobrovolný, Petr - Zahradníček, Pavel - Štěpánek, Petr - Janouš, Dalibor - Cienciala, E. - Žalud, Zdeněk
Observed and predicted changes in the water balance of the Czech landscape– facts and some consequences.
Quo vaditis agriculture, forestry and society under Global Change?: Book of abstracts. Brno: Global Change Research Institute of the Czech Academy of Sciences, 2017. s. 9. ISBN 978-80-87902-20-2.
[Quo vaditis agriculture, forestry and society under Global Change? 02.10.2017-04.10.2017, Velké Karlovice]
Institucionální podpora: RVO:86652079
Klíčová slova: water requirements * agriculture * vegetation dynamics
Kód oboru RIV: DG - Vědy o atmosféře, meteorologie

The quantification of changes in water requirements and the outlook for coming decades
corresponds to the recommendation of the recent strategic documents. The water requirements
for agriculture were estimated at 500x500 m grid for the entire territory of the Czech Republic
based on daily weather data, slope and aspect, soil water holding capacity and potential
influence of groundwater. The estimates included also vegetation dynamics as well as sowing
/ sowing / sensitive period / harvest timing in relation to the weather patterns of the given year
and other key factors influencing the water need (e.g. varying leaf area and root depth). The
effect of increasing ambient CO2 on the water regime of plants was also included. The available
water resources were estimated on the basis of the BILAN monthly balance model, and the
impacts of both the water management system and actual withdrawals and discharges were
taken into account in the calculations. Compatibility between the BILAN and SoilClim
parameters was ensured by their integration. For better interpretability, the management of
water resources and their availability has been analyzed both at the level of individual
catchments and their integration. The findings for the period from 1956 to 2016 clearly shows
tendency towards more frequent and severe droughts toward the end of the period and with
major drought events occurring during 1990´s. It also showed the severity of 1947 event that is
however comparable to those observed in 2003 and 2015. The projections for the upcoming
decades clearly indicate much higher probability of both agricultural and hydrological drought.
When the modelling cascade was used to assess adequacy of water resources for the current
level of withdrawals and consumptions it became clear that in some catchments (e.g. Thaya
river) would not have sufficient resources to meet the demand even during mild drought
episodes by 2030´s.
Trvalý link: http://hdl.handle.net/11104/0276548