![]() ![]() ![]() On many photographs not only the principles of their work are illustrated but also the faults and failings of an individual sundial. The book deals especially with the sundials which work on a principle of an hour angle. (Sundials - designs, implementations and examples from the native country and from around the World) Sluneční hodiny - návrhy, realizace a příklady z domova i ze světa ![]() The introduction of species of palaeo-neophytic genera and sub-Mediterranean species is discussed as a measure to buffer negative effects on native species caused by climate change and spread of novel diseases.New book about sundials Title of the book We introduce the concept of palaeo-neophytes to address genera that existed in Central Europe during the latest Cenozoic. It should be an aim of silviculture to ensure this in the future and (4) only 22 of the indigenous tree species are commercially used nine of these commercially used species are threatened by diseases. No loss in vascular plants restricted to forests occured over the past 250 years despite of forest management (2) the indigenous arboreal flora has a low diversity (64 tree species) compared with other continents due to environmental changes in the last 2 million years (3) forest management has maintained a high plant diversity in the past. Vascular plant species confined to forests comprise about 10 % of this flora. We show that (1) diversity of the German vascular plant flora increased exponentially during the Holocene reaching 3874 species mainly through apomictic and hybrid speciation. Here, we assess forest management strategies for maintaining plant biodiversity in Central European beech forests, with a focus on Germany. A better understanding is mandatory to ensure conservation and appropriate management of biodiversity and ecosystem functions in the face of climate warming and increasing demand for wood products. The impact of historical and present drivers on forest biodiversity is poorly understood. chondrilloides has characteristics that allow it to respond rapidly to degradation and restoration of its habitats along gravel rivers in the Eastern Alps. Populations in the southern parts of the species’ range are larger with bigger plants and more reproduction, while germination is very high in all populations. Chondrilla chondrilloides forms meta-populations on consolidated gravel bars and older terraces, with extinction and recolonisation due to floodplain dynamics small populations quickly recover from few founder individuals. A summary on location, size and structure of the remaining populations in the north-eastern and south-eastern Alps is combined with data on seed germination and the habitat niche of the species, with a particular focus on differences between northern and southern populations. The review is complemented by own research data and a phylogenetic assessment of extant and extinct populations within the infrageneric context. This paper summarises the published material on taxonomy, morphology, habitat requirements and distribution of the species. Its population declines were caused by habitat fragmentation and destruction as a consequence of extensive hydro-engineering. The species was common along Alpine gravel rivers, but has declined markedly due to river regulation and degradation in the 19th and 20th century, while some recent restoration projects benefit the plant. Its distribution is restricted to near-natural braided rivers and to alluvial fans. Chondrilla chondrilloides (Asteraceae) is a rare and endangered early-successional plant species endemic to the Eastern European Alps. ![]()
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