Fluctuations of floods of the River Morava (Czech Republic) in the 1691–2009 period: interactions of natural and anthropogenic factors

Abstract

Floods from the middle part of the River Morava (eastern Czech Republic) are considered over the course of the past three centuries, the study being based on data derived from documentary evidence (1691-1880), measured peak water stages, H k (1881-1920) and peak discharges, Q k , evaluated with respect to their N-year return period (H N and Q N ). Changes in land use and water management (water reservoirs, channel modifications) are discussed, as are factors influencing runoff conditions in the Morava catchment. Decadal synthesis of flood series identifies the highest flood activity in the decades of

Floods and floodplain changes of the River Morava, the Strážnické Pomoraví region (Czech Republic) over the past 130 years

“…It follows from the above analysis that we are dealing with a very complicated system, in which further research and consideration of other effects (land-use and climate change), discussed in more detail in a further paper by Brázdil et al (2011), may contribute to a better understanding of the interrelationships between floods, human impacts (e.g. channel modifications, land-use changes) and floodplain development.…”

“…Using these two stations introduces no additional uncertainty into frequencies, because the River Morava has no important tributary influencing its discharges between Rohatec and Uherské Hradiště (see also Table 2). Moreover, the floods we selected for before 1921 are supported by flood data from southeastern Moravia gathered from documentary evidence (such as newspapers, chronicles and economic records) that are related to events with overbank flow and inundation of the floodplain (for more details, see Brázdil et al 2006Brázdil et al , 2011. However, it is difficult to evaluate the severity of floods from measured water stages (before 1921), because calculation of discharges applying hydraulic equations would be significantly biased by the unknown cross-section of the channel.…”

“…The maximum frequency of floods in 1961-1980 can be related to the most significant changes in land use associated with the process of "socialist collectivization" in agriculture. An increase in the area of arable land and reduction in permanent grassland significantly decreased the retention capacity of the landscape in the River Morava catchment (Skokanová 2009, Brázdil et al 2011.…”

“…The study of floods in the Strážnické Pomoraví region over the past 130 years requires that changes in the primary influencing factors, such as land use, climate and civil engineering, has to be taken into consideration. Changes in land use in the Morava catchment above the Dyje tributary have been characterized by Brázdil et al (2011) in terms of four time spans: 1836-1841 (standard agriculture), [1952][1953][1954][1955][1956] ("socialist collectivization" of agriculture), 1988-1995 (change of political system) and 2002-2006 (free market economy). The whole period has been characterized by a continuously increasing proportion of forested area (from 28.4 to 37.3%).…”

“…Recent land-use in the Morava catchment above the confluence with the Dyje is represented mainly by arable land (41.5%) and forest (37.3%), with some permanent grassland (11.5%) and built-up areas (7.4%). None of the other land-use categories (orchard; vineyard and hop-garden; water area; recreational area; other area) exceeds 1% of the Morava catchment in extent (Brázdil et al 2011).…”