Causes of water erosion and benefits of antierosion measures in model locality starovice - Hustopeče (South Moravia Region, Czech Republic)

Abstract

The agricultural land found in the Czech Republic is strongly degraded by water erosion. The main reasons for this situation are the changes in the landscape caused by large-area agricultural production in the second half of the 20th century. In the model locality Starovice - Hustopece (223.5 ha) (South Moravia Region), we analysed the changes in the landscape structure and land use for the period 1825-2018. In 1825, the mean size of a land block was 0.4 ha. In 1968, the studied locality consisted of just one land block of a size of 223.5 ha. This period marks the beginning of massive water erosion. In 2003, the locality was proposed for land consolidation. Its goal was to reduce erosion and the risk of floods. To date, a number of protective measures have been applied in the locality. The risk of water erosion was assessed for the landscape state in 1968 and 2018 in GIS using the USLE method. The effect of the adopted measures was strongly manifested in the reduction of the erosion risk (by 44%). The transport of sediment out of the locality was assessed for 1968 and 2018 by means of the WaTEM-SEDEM model. The protective measures resulted in a decrease of sediment transport out of the locality by 111 t/year (40% reduction). The economic balance of the soil loss showed a positive impact of the applied protective measures. On the basis of the mean price of arable land in the Czech Republic and the costs of the soil relocation within the locality, the application of protective measures brought an economy of at least € 5,000 per year. This sum does not include the losses caused by a potential decrease of agricultural crop yields due to the soil degradation, reduction of ecosystem services, and other factors in the past years. The actual benefits of applying the protective measures aimed at reducing erosion and increasing water retention in the landscape are significantly higher.