UNIVERSITY of PÉCS Investigation of the Changes in the Urban Flora In

UNIVERSITY OF PÉCS Biological and Sportbiological Doctoral School Investigation of the changes in the urban flora in Pécs with special regard to the naturalisation of the common fig ( Ficus carica L.) PhD Thesis Tamás Wirth Supervisor: János Csiky PhD Pécs, 2020 INTRODUCTION In our rapidly changing world urbanisation is one of the greatest threats on biodiversity (MCKINNEY 2006, KNAPP et al. 2008, HAHS et al. 2009). As 68% of the world's population will live in cities by 2050, urbanisation processes will have an increasing impact on settlements and their wider environment. (WILLIAMS et al. 2015). Human settlements were often established at or near local diversity centres (ARAÚJO 2003, KÜHN et al. 2004), making these areas and their biota particularly vulnerable. Europe is one of the most urbanized continents in the world, with 73% of its population living in cities (UNITED NATIONS 2015). By changing ecological conditions and the composition of biota, the urbanisation processes of the last two centuries have significantly transformed Europe's landscape and habitats. (SUKOPP 2002, BLAKE et al. 2011, ELGUINDI et al. 2013, WILLIAMS et al. 2015). Urbanization is accompanied by the fragmentation of natural and semi-natural habitats in the immediate and remote surroundings of settlements, the disappearance of native species, and the introduction of alien species (PYŠEK 1993, KOWARIK 1995, CHOCHOLOUŠKOVÁ és PYŠEK 2003, MCKINNEY 2006, BRUNZEL et al. 2009, HAHS et al. 2009). The urban environment therefore strongly filters the local flora and allows only species with certain characteristics to survive, therefore urbanization is leading to an increasing similarity of urban flora globally, i.e. to the biotic homogenization of settlements (DOLAN et al. 2017). In order to make our environment more colourful and enriching, we are planting and introducing more food and ornamental plants to human settlements - and many weeds together with them - therefore our cities have become foci for alien plant species (PERGL et al. 2016, ČEPLOVÁ et al. 2017). The species established here may expand further from the settlements towards the less urbanized areas. As settlements create increasingly similar abiotic and biotic conditions for plants as a result of globalization, the spread of some species is also accelerating at the continental level. Due to the urban heat islands and the current trend of climate change, the introduction and spread of thermophilous species in populated areas is expected. (LOSOSOVÁ et al. 2018). Most urban flora surveys were conducted in Central and Western Europe (e.g. LOSOSOVÁ et al. 2012), a much more modest number of such papers have been published in Southern and Eastern Europe (e.g. MOSYAKIN és YAVORSKA 2002, CELESTI -GRAPOW et al. 2013). As a result, the validity of the conclusions reached on the subject at the European level is highly questionable. Despite the international popularity of this topic there are only a few examples of surveying the flora of settlements or parts of settlements in Hungary (e.g. DÉNES 2010, HÜSE et al. 2016). In this case, the authors focused mostly on the wider environment of a 2 settlement and primarily on the exploration of the flora of near-natural areas (e.g. NAGY és MALATINSZKY 2019). To this date, no work has been published in Hungary which aims were the systematic survey of the entire flora of inner and peripheral urban areas. As a result, we know almost nothing about the species richness of urban areas, on the changes in their flora, on the distribution and dynamics of native and non-native species occurring in them, and the factors threatening their flora in Hungary. In my work, I examined the flora of the most populous city of Transdanubia, Pécs, in order to reduce the deficiencies listed above. I primarily did this by examining the richness of species and changes in species composition, as well as through the exploration of patterns in native and non-native plant species. To finish, I illustrate one of the possible hypothetical effects of climate change on urban flora - resolving a century of polemics - by proving the naturalisation of Ficus carica in Hungary. 3 AIMS In the coming decades, due to increasing urbanization and climate change, research on urban areas can play a key role in preserving biodiversity, preventing the establishment of new plant species and possible plant invasions. This is especially the case in Hungary, where the study of the settlement flora lags far behind, even in an international context. In order to reduce these gaps, my work compares pre-20th century urbanization and post-urbanization flora, i.e. I examined the changes in the urban flora during the last 70 years in the case of Pécs, the most populous city in Transdanubia. My aim was also to investigate and characterize the current composition, species richness and spatial distribution of species and species groups in the flora of Pécs. The Hungarian settlements can serve as a foci and later as a kind of springboard for the non-native, thermophilous plant species in the country. An illustrative example of these non-native, thermophilous plant species in Hungary is the common fig. It is widely grown and distributed in Hungary, which taxon through its adaptability allows the real-time, direct study of the establishment of an adventitious plant species in Hungary. In light of this, I was looking for answers to the following questions in my dissertation: 1. After 72 years (1942 vs. 2014) what changes can be detected in the flora of Pécs based on the life-form and dispersal types of plant species, the number of species, and the immigration status of the plant species? 2. What spatial trends are characteristic of the native plant species, archaeophytes, neophytes, and protected vascular plant species found within the city? 3. What is the relationship between the above-mentioned groups of species and the proportion of built-up areas, forest areas and between the average altitude of the sampling units? 4. Which species are the most common and what are the characteristics of the most widespread taxa in the city based on binary data? 5. Can the appearance, spread and/or establishment of Ficus carica be detected in the city? 4 MATERIALS AND METHODS Study area Pécs, (excluding Budapest) is the fourth most populous city in Hungary and the most populous in Transdanubia. The extent of the current administrative area of the settlement is 162.77 km 2, and its population size is 144 586 inhabitants (KSH 2019). It is a very diverse area in terms of geology and geomorphology, as well as phytogeography and floristics (KIRÁLY et al. 2008, DÖVÉNYI 2010, BORHIDI et al. 2012). Flora mapping and species lists Floristic data collection was carried out between 2008 and 2014 in rectangular sample units of a regular grid. The floristic survey carried out following the protocol on the Hungarian Flora Mapping System (KIRÁLY 2003, BARTHA et al. 2015). The units of the Hungarian Flora Mapping System were divided into 16 equal units (~2.2 km 2 sized grid units) following the graticule. A total of 104 of these plots cover (completely or partially) the present administrative area of the city. The study area represents a larger area (~ 225.5 km 2) than the administrative area of Pécs and includes its immediate vicinity as well. Consistent with FORMAN ’s (2014) concept, the surveyed grid units represent the city area (Pécs) and parts of the settlements in the agglomeration area (Bogád, Cserkút, Hosszúhetény, Keszü, Kozármisleny, Kökény, K ővágósz őlős, Martonfa, Pereked, Pécsudvard, Pogány, Romonya), including the farmlands and/or semi-natural forests of the peri-urban and/or exurban zones as well. During the field survey, we used a 1: 25.000 scale military map, and later used the grid system installed on GPS and smartphone. Each unit was surveyed three times, in spring (between late February and early May), and in early and late summer (between late May and early September). We recorded and compiled data exclusively of the spontaneously occurring species; planted and clonally growing escapes were not added to the species lists. Cases, where it was not clear whether the specimen appeared in the area as a result of vegetative propagation were also excluded from the survey. The taxonomically critical species (e.g. Hieracium microspecies, Verbascum and Viola hybrids) were not taken into account. Some critical species, which are easily confused with each other in certain phenological conditions, were grouped into a total of 42 species aggregates. The nomenclature of species follows KIRÁLY (2009). For species missing from this work I considered the ‘The Plant List’ database [1]. 5 For the temporal studies, I used the work of Adolf Olivér HORVÁT from 1942. Species occurrences in Horvát's flora work were assigned to the respective grid cells in which their locations were found. The data of those locations, which related to multiple grid cells due to their size or extension, were assigned to each of the related cells. If a species was listed as 'common' by Horvát, we assigned the species to every grid cell. The same method was used in the assignment of the data published between the two dates to the grid system. Trait data Among the characteristics of the species detected in the administrative area of the city, I examined the immigration status, the life-form and the dispersal type, the conservation status and the chorological type. To determine the indigenous categories of species (natives, archeo- and neophytes) I used the works of PYŠEK (1995a), TERPÓ et al. (1999), BALOGH et al. (2004), and KIRÁLY (2009). The life-form and chorological types of the species were based on the work of HORVÁTH et al. (1995), while the determination of the dispersal types of the species was based on the works of SOÓ (1964, 1966, 1968, 1970, 1973, 1980).

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