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Response of forest succession to agricultural land-abandonment in the Giant Mountains
Dobíhal, Michal ; Treml, Václav (advisor) ; Chuman, Tomáš (referee)
Response of forest succession to agricultural land-abandonment in the Giant Mountains ABSTRACT: Since the end of the 19th century, there is undergoing process of land-abandonment of mountain meadows and pastures in most of the European mountains, including the Giant Mountains. Mountain agriculture in the Giant Mountains was terminated no later than before World War II. Abandoned meadows were then subjected to secondary forest succession. The question is, how fast was this succession and how was its dynamics. My research was focused on 4 areas of interest, located in the vicinity of former mountain huts. Methods applied included the analysis of historical maps and aerial photographs and dendrochronological research of age structure of Norway spruce (Picea abies) stands. The aim of this thesis was to find out the extent of mountain agriculture near the huts and the dynamics of forest succession following land abandonment. Main peaks of seedlings establishment were observed in a very short time (10 - 20 years) following termination of mountain agriculture and in most cases these peaks were further followed by one or two more weaker peaks in the later periods. These peaks became evident in the change maps of forest development with approximately 20 years delay. Forest succession was moving gradually from the...
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The Glacial Retreat in the Cordillera Blanca since the Littel Ice Age
Dobíhal, Michal ; Vilímek, Vít (advisor) ; Emmer, Adam (referee)
Michal Dobíhal Studijní program: Geografie Studijní obor: Fyzická geografie a geoinformatika Bakalářská práce Vedoucí práce, školitel: Doc. RNDr. Vít Vilímek, CSc. The glacial retreat in the Cordillera Blanca since the Little Ice Age ABSTRACT: The term Little Ice Age refers to a cooling period of time, as a result of this cooling mountain glaciers experienced significant advance in many parts of the world. Conventionally, the period between the 16th century and the middle of the 19th century is stated for the Little Ice Age, but its course and time placement differs in individual world regions. Based on research of scientific literature, this thesis aims at describing correct time placement of the Little Ice Age in the southamerican mountain range Cordillera Blanca and the expanse of the glacier retreat since its maximum till the present. Methods of lichenometry used for dating "Little Ice Age" moraines are mentioned as well. In the analytical part, the area of the glaciation of selected glaciers from the Little Ice Age maximum and from the present is compared using polygon measurement and satellite images. The extrapolation of this method is subsequently made on other selected glaciers, whose moraines have not been dated yet. Keywords: Cordillera Blanca, Little Ice Age, glacial retreat, moraine, lichenometry
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