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Many studies have recently been devoted to the study of landscape change, and some have even focused on an analysis of the dynamics of forest cover change. However, few of the studies have worked on a methodology for making a detailed investigation of long-term forest change dynamics based on historic cartographic sources. The goal of this study is to further develop a method for analyzing long-term changes in forest cover on the basis of old maps and orthophoto maps in the GIS environment. The study area is located in Central Bohemia, to the east of Kutná Hora, a UNESCO World Heritage Site. The area consists of 21 cadastral units with a total area of 113 km 2 . The maps of the First (1780), Second (1851) and Third Military Surveys (1877) and the present-day orthophotomap (2007) of the Czech Republic were used as data resources. Source data have been processed in GIS. Forest cover is the subject of our study. However, the term is perceived from a broader perspective. What we call forest cover in our study refers to forest wood elements and other wood species in the landscape. In this study, forest cover has been structurally considered as a whole, without dividing it into the two categories mentioned. We counted the extent of the forest cover in each particular time horizon in hectares and as a percentage of the area under study, also the absolute changes in forest cover between the individual time horizons in hectares as well as the intensity of the changes in forest cover in hectares per year. The spatial changes in forest cover were evaluated in a GIS environment using specialized features to analyze spatial variation. The forest cover occupied 16.60% (1,880 ha) of the total area in the First Military Survey (1780). In 2007, the proportion was slightly higher at 16.64% (1,884 ha). More than half of all forest land (53%) from the time of the Second Military Survey (1851) survived until 2007. Not only the information on absolute changes but also the information on the rate of change is of great importance. The old Military Survey maps and the orthophotomap enable us to carry out studies of long-term changes in forest cover. However, the geodetic inaccuracy of the First Military Survey maps precludes reliable and exact quantification of the landscape changes between the First Military Survey and the Second Military Survey, and also between the First Military Survey and present-day (orthophoto map). These maps cannot be used for evaluating forest cover changes on the level of individual plots. The method presented in our paper may contribute to a better understanding of the long-term dynamics of forest land, covering a period of more than 250 years. This knowledge can be applied in forest management planning procedures. Apart from their application Communicated by J. Müller.

Abstract:The landscape of the Czech Republic currently faces droughts that are caused by several factors. One of the reasons for drought is landscape development and land cover changes. Changes in water and wetland areas and streams were studied by comparing old military maps and the present state. Water and wetland areas in fertile lowlands significantly decreased over time; the landscape was continuously dried out with the aim of increasing agricultural and woody production. While water and wetland areas occupied nearly one-third of the study area (Nové Dvory and Žehušice micro-regions in Central Bohemia) at the end of the 18 th century, the present share of these areas is only 3.5%. There was a decrease of approximately 10% in each period, and nearly all of these areas disappeared by the end of the 19 th century. Water and wetland areas were changed primarily to arable land. The length of streams decreased by the end of the 19 th century. Drainage and irrigation channels were built during the 20 th century, and although they are only periodic or episodic streams, these channels increased the total length of streams.Key words: streams, still waters, wetlands, land use changes, drought, central Europe Abstrakt: Krajina České republiky v současnosti čelí nebezpečí sucha, které je způsobeno mnoha faktory. Mezi ně patří změny krajiny a krajinného pokryvu. V článku jsou sledovány změny vodních a mokřadních ploch a délky vodních toků na podkladě starých vojenských mapování a současného stavu. Vodní a mokřadní plochy v nížinách zásadně ubyly a krajina byla vysušována s cílem zvýšit zemědělskou a lesnickou produkci. Zatímco na konci 18. století vodní a mokřadní plochy zaujímaly skoro třetinu sledovaného území Novodvorska a Žehušicka ve středních Čechách, v současnosti je to jen 3,5 %. V každé ze sledovaných period ubylo přibližně 10 % jejich rozlohy, významný úbytek těchto ploch v krajině tak nastal již v 19. století. Vodní a mokřadní plochy byly změněny převážně na ornou půdu. Délka vodních toků poklesla zejména v průběhu 19. století. Současná data ukazují nárůst jejich délky, který je ale způsoben budováním zavodňovacích a odvodňovacích kanálů, jejichž délka je také započítána do celkové délky vodních toků, byť nejsou celoročně protékány vodou.

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