Since the 19th century, the irrigation industry on the territory of the Czech Republic has undergone considerable technological development and an increase in irrigated areas. Irrigation has become an important part of the Czech landscape. Large complex irrigation systems of tens to hundreds of km2 have been built. Towards the end of the 20th century, there was a significant decline due to the change of political regime, abolition of agricultural companies, etc. Irrigation systems and buildings were often destroyed, devastated, left without maintenance. There have also been several changes in the administrative management of the irrigation sector. The consequence was that there was no single database of irrigation systems. At present, a database of these irrigation systems is being compiled by the Research Institute for Soil and Water Conservation using geographical information systems (GIS). In connection with climate change, the threat of drought, and irregular distribution of precipitation during the growing season, and the issue of irrigation are back on trend. In this study the current state of irrigation systems in the Czech Republic was presented. In the Czech Republic, a total of 175115 ha of irrigation area has been recorded so far (of this area, about 41% is currently in functional). Selected historic irrigation structures were documented by unmanned aerial vehicles (UAV).
In the projects of anti-erosion protection in the Czech Republic, USLE was used as a standard tool for evaluating the risk of water erosion. The precision of the resulting USLE values is defined by the quality of input data and algorithms used. Two methods for LS factor calculation are recommended for use in the planning practice in the Czech Republic: the computing method based on the USLE 2D software and the other computing methods. Various methods can assess the LS factor; however, their results differ. On the example of the Starovice – Hustopeče study area (Czech Republic), strongly threatened by erosion, this report aimed to show the differences brought using these differing methods of LS factor assessment, all in two variants before and after application of antierosion measures (retention grass belts, grassed thalweg). Changes in the calculation of the LS factor were directly reflected in the calculation of the long-term average soil loss by water erosion.
The water retention capacity of a territory is mainly defined by the land conditions, type of soil cover and manner of land management. The manifestations of the climate change reflect the need for better water capture from precipitation in agricultural catchment areas. The effect of the soil cover on the water retention capacity was studied in two localities with different soil types (chernozem and cambisol). The results have shown significant effects of permanent grass covers on increasing the water retention capacity. The mean retention capacity measured at permanent grass covers was 1.7-fold higher than at arable land. The soil type did not play a significant role. To some extent, the retention capacity is also influenced by the used agro-technology. After stubble-tillage, the water from precipitation was better infiltrated by arable land than by permanent grass cover. However, during a major part of the vegetation period, arable land is at the rest, and the short-term increase of its retention capacity has no impact on the overall outcome.
The increasing risk of wind erosion in the context of climate change represents a highly pressing issue. This increase is a result of the growing occurrence of droughts and elevated temperatures in the intensively farmed areas. Effective protection against the wind erosion can be provided by windbreaks, especially during the period when the soil is not protected by the vegetation cover of crops. In this report, the authors wanted to compare the methods defining the windbreak protection zones. The optical porosity and the windbreak height were the basic parameters for defining the protection area. The various methods differ among themselves by using the windbreak height parameter or not. The optical porosity of the windbreaks was determined based on photographic documentation. For the comparison, the cadastral area of Micmanice was selected due to the wide network of windbreaks in this locality. A database of windbreak height and optical porosity for each windbreak was set up. Our report thus presents the application of the new knowledge aimed at updating the methods and procedures for assessing the vulnerability of the area by wind erosion. The application of the method involving the optical porosity and windbreak height parameters resulted in a significant reduction of the windbreak protection zone compared to the method omitting the windbreak height.
The aim of this study was to identify the tile drainage systems within the year (from spring to autumn) using the ground penetrating radar (GPR) geophysical method. The measurements were performed in the experimental locality Dehtáře in the Bohemo-Moravian Highland (Czech Republic) in the years 2016 and 2017. The profiles located in the drained area were repeatedly measured together with the drainage discharges, soil moisture and groundwater level. The best visibility of tile drains was observed during snowmelt (in March and April) when the drainage discharges usually reach their maximum. In other months, the visibility of the drains was variable, but mostly worse. For a reliable detection of individual drains, the measurements above the drainage must be performed in several profiles. Under the conditions of the Czech Republic, the best results were obtained by a 500 MHz frequency antenna.
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 – Hustopeče (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.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.