Brandes, D. (1985): Die spontane Vegetation toskanischer Städte. - Tuexenia, 5: 113-125. The spontaneous vegetation of Tuscan towns (Firenze/Florence, Prato, Lucca, Arezzo, Siena, San Gimignano)is shown by plant sociological relevès and species lists. A clear relationship to city structure can be seen. While species with broad ecological and sociological amplitudes are found in city centers the ruderal vegetation is developed optimally at the ancient outskirts of the towns. The transitional state of the investigated cities is shown by the fact that nitrophilous skirt communities are remarkably frequent, while mediterranean ruderal communities of the alliance Hordeion leporini are relatively poorly represented. The spontaneous vegetation of Tuscan towns possesses a great number of species common also to cities in central Europe, but the number of common associations is very small.
Brandes, D. (1989.1992): Geographischer Vergleich der Stadtvegetation von Mitteleuropa. - Braun-Blanquetia, 3: 61-67. For reaching universally valid statements for urban vegetation, investigation of towns in different regions is necessary. By geographical comparisons it is possible to point out analogies as well as differences. Four comparisons will be discussed here:
Number of adventitious species in towns.
Total number of species in towns. As a result of the different demarcations of urban areas there only few data available. The number of species is - in common - rising both with area and number of inhabitants.
As a "minimal program" the spontaneous flora of old cities is mapped. The first results of 23 towns are discussed.
For a number of towns in Northern central Europe the ruderal vegetation is compared. To the common stock of plant communities belong among others Hordeetum murini, Malvetum neglectae, Echio-Melilotetum, Artemisio-Tanacetetum and Lolium perenne-Plantago major community.
Brandes, D. (1989.1992): Spontane Vegetation von ligurischen Küstenorten. - Braun-Blanquetia, 3: 229-245. A program for comparative investigations of the vegetation of settlements in Europe is presented with some ligurian coastal villages and towns as an example. Therefore the spontaneous flora and vegetation is investigated for several types of biotops as there are old towns, historical fortifications, modern districts, gardens, railway land, fallows and river banks. The densely build-up old towns are very poor in species; there are mainly to be found nitrophilous and ? shaddow tolerating species. Especially rich in species are the riverbeds of the torrents as well as the surroundings of old castles. The documentation of the vegetation concerning the types of biotops enables also comparisons beyond different floristic provinces.
Brandes, D. (1992): Flora und Vegetation von Stadtmauern. - Tuexenia, 12: 315-339. This paper deals with flora and vegetation of city walls in various parts of central, western and southern Europe (Germany, France, Luxembourg, Italy, Malta, Mallorca [Spain], and Portugal). Special importance is assigned to registration of the floristic diversity. The relation to various influences such as building materials of the walls, conservation of the walls, and surrounding are investigated. Areas of city walls with quasi-homogeneous vegetation are documented by plant-sociological relevés. In central Europe north the Als, the spontaneous plant species of city walls are first of all ruderal plants, but woodland species, plants of Sedo-Scleranthetea and Festuco-Brometea appear too, whereas Aspenietea species except Asplenium ruta-muraria and Cymbalaria muralis are of less importance. In winter-mild areas of France, Parietarietalia species are much more frequent in wall joints than in central Europe. This applies also to the southern foothills and valleys ot the Alps. In the western mediterranean area, Parietaria judaica is the most common species of the city walls, while Capparis spinosa, Antirrhinum siculum or Antirrhinum majus ssp. linkianum may dominate locally. Species diversity is often very high in old city walls. Wall tops, wall joints and the bases of walls are important refuges for a number of endangered synanthropic species. Therefore, city walls are of great importance for nature protection, especially in lowlands. Problems between nature conservation and protection of monuments are also discussed.
Brandes, D. (1995): Flora of old town centres in Europe. - In: H. Sukopp, M. Numata & A. Huber (eds.): Urban ecology as the basis of urban planning. The Hague, p. 49-58. The spontaneous floras of 66 old town centres have been compared in different regions of Europe (Germany, France, Belgium, Austria, Switzerland, Italy, and Portugal). Similarity as well as geographical variability of the old town floras are studied. Our investigations show that the number of common species in old town centres of central and/or West Europe is high. Similar climatic conditions in old towns of the western part of the mediterranean area also lead to relatively uniform stocks of plant species. Differences between the floras of old cities and old villages are pointed out.
