This paper deals with the species composition of epiphytic lichens in Central European oak forests. A total of 192 oak trees at 48 localities in the Czech Republic, Slovakia and Hungary were investigated. In total, 104 lichen species were recorded and divided into three groups in accordance with their frequency of occurrence on trees within the area. The importance of abiotic factors affecting species composition was assessed by multivariate statistics. Principal component analysis illustrated that lichen assemblages reflected geographical distribution of localities and that the occurrence of many species is closely associated with several environmental factors. In particular there is a high negative association with pollution, and positive associations with precipitation, solar radiation and basic bedrock. The variation partitioning estimated the influence of environmental parameters, human impact and naturality factors on lichen composition. Cluster analysis recognized six communities of lichens, of which the members differed from those in the other communities in their autecological characteristics. Two of the communities can be assigned to Parmelion caperatae and Pertusarion amarae and seem to be similar to natural lichen communities of oak forests in Central Europe. Possible reasons for absence of several epiphytic lichen associations (Lobarion pulmonariae, Pertusarion hemisphaericae) in the forests studied is discussed and the species composition in Central Europe was compared with the lichen assemblages in oak forests in neighbouring regions (western Europe, Scandinavia). On the basis of these findings several indicative species of close to natural oak forest are suggested (Acrocordia gemmata, Bacidia rubella, Calicium spp., Caloplaca lucifuga, Cetrelia olivetorum s.l., Chrysothrix candelaris, Flavoparmelia caperata, Melanelia subargentifera).
The paper deals with the problem whether the number is a property or an object. The authors are convinced that from the logical point of view the number is an object, but from the ontological point of view the number is a special kind of property (briefly spoken the property of a system or a structure). and Prokop Sousedík, David Svoboda
According to the positivists, all our knowledge is based on experience which is the foundation not only of every empirical science, but also of those disciplines that are usually considered to be a priori. The paper consists of two main parts. Firstly, a positivist concept of number defended by J. S. Mill is presented; secondly, it is shown how this conception can settle some objections coming from apriori-oriented philosophers. Mill’s theory of number is interesting for at least two historical reasons. It is developed in connection with a relatively rich scholastic logic which is why its methodology is similar to the contemporary philosophy of language; it is indispensable for an appropriate comprehension of the concept of number that was proposed by Mill’s most famous opponent G. Frege., Podle pozitivistů jsou všechny naše znalosti založeny na zkušenostech, které jsou základem nejen každé empirické vědy, ale také těch oborů, které jsou obvykle považovány za a priori . Příspěvek se skládá ze dvou hlavních částí. Nejprve je prezentován pozitivistický koncept počtu obhajovaných JS Millem; Za druhé, je ukázáno, jak tato koncepce může vyřešit některé námitky z apriori-orientovaných filozofů. Millova teorie čísel je zajímavá alespoň ze dvou historických důvodů. Je rozvíjena v souvislosti s relativně bohatou akademickou logikou, proto je její metodika podobná současné filosofii jazyka; je nepostradatelné pro vhodné pochopení pojmu čísla, který navrhl nejslavnější oponent ml. G. Frege., and Prokop Sousedík, David Svoboda
The paper deals with a type of whole and part that can be found in Aquinas’ work and to which no attention has been paid so far. This type of whole and part can be called metaphysical whole and metaphysical part, respectively. In the paper, metaphysical whole and part are put forth on the problem of the logical and metaphysical structure of a common nature., Příspěvek pojednává o typu celku a jeho části, které lze nalézt v díle Akvinského a na které dosud nebyla věnována pozornost. Tento typ celku a části lze nazvat metafyzickou celou a metafyzickou částí. V příspěvku jsou metafyzický celek a jeho část uvedeny na téma logické a metafyzické struktury běžné povahy., and David Svoboda
A systematical exposition of the concept of number cannot be found in Aquinas’ works. Nevertheless, there are many places where the problem is touched. The problem is encountered on the one hand within the discussion of the category of quantity and on the other hand when Aquinas speaks about transcendental concepts and deals with the problem of numerical statements concerning God. The aim of the paper is to reconstruct, on the basis of Aquinas more or less fragmentary ideas, his concept of number., Systematický výklad pojmu čísla nelze nalézt v dílech Akvinů. Existuje však mnoho míst, kde se problém dotýká. Problém se objevuje na jedné straně v rámci diskuse o kategorii kvantity a na druhé straně, když Aquinas hovoří o transcendentálních pojmech a zabývá se problémem číselných tvrzení o Bohu. Cílem příspěvku je rekonstruovat na základě Akvinů více či méně fragmentární myšlenky, jeho koncept čísla., and David Svoboda , Prokop Sousedík