Research Article |
Corresponding author: Ákos Malatinszky ( malatinszky79@gmail.com ) Academic editor: Bela Tóthmérész
© 2019 Károly Menyhért Nagy, Ákos Malatinszky.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Nagy KM, Malatinszky Á (2019) Unique botanical values in a metropolitan area and the landscape history reasons of their occurrence on the Széchenyi Hill, Budapest. Nature Conservation 32: 35-50. https://doi.org/10.3897/natureconservation.32.30807
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Urban areas host several threatened species in small reserves that face habitat loss and fragmentation due to land-use change. Despite historical and current disturbances, these areas sometimes still maintain high biological diversity. As only 5% of the European Union territory was classified as natural, the permanent grasslands represent overriding value, especially in metropolitan areas. Our aim was to explore protected and adventive plant species in a small and valuable, but till now, not deeply studied area of the densely inhabited 12th district in the metropolitan city Budapest (Hungary), which is visited by large numbers of people. We compared various historical map sources in order to explain how the extension of the grasslands has changed during the past centuries and, thus, which patches are permanent grassland habitats. We found 29 protected and 1 strictly protected plant species. The highest number of protected plant species and their stands were found in the permanent grasslands. Besides urbanisation, a heavy load of tourism (especially on non-designated routes), off-road mountain biking, airsoft races, some illegal shelters for homeless people and game damage threaten this unique refuge of high natural values. The extension of grasslands between 1783 and 2016 varies from 6.7 ha to 21.5 ha. Their area constantly increased due to deforestation until 1867 and exceeded 20 ha, probably due to the mass increase in livestock grazing; then it stagnated until the 1920s, with a slight decrease due to expanding urban areas. Golf greens appeared, walker and skiing tourism increased and these apparently have not decreased the coverage of grasslands, but surely affected the composition of their species. Recent scrub encroachment and re-forestation caused a further decrease. Our distribution maps show the highest density of protected plant species on the southern slopes (2.4 hectare) that have constantly been grasslands since 1783 to date. Contrarily, the cutting of grasslands from 1861 to date contains only half of their number per area unit. Thus, the number of valuable plant specimens refers to the age of the grassland. Three species occur only in the oldest grasslands. Conservation actions should first and foremost focus on these patches.
Adventive plant, conservation, environmental history, grassland, protected plant, protected area management, urban areas
Urban areas occupy less than 0.5% of the Earth’s total land area (
The effectiveness of different-sized reserves has been studied for about a century, with early warnings on the positive relationship between species richness and area (
The flora of Hungary’s state capital, Budapest, has been investigated since the 18th century. However, constant changes justify regular monitoring of protected species to recognise threats as well. Our aim was to prepare distribution maps of protected and adventive plant species in a small and valuable, but till now, not deeply studied area of the densely inhabited 12th district in the metropolitan city Budapest, visited by great numbers of people. We also aimed to explain how these unique species could survive despite anthropogenic effects (including land use change, expansion of built-up areas) through millennia and constant disturbance (including inhabitation and urbanisation). Seeing that the majority of protected species are hosted by grassland habitats, we explored the landscape history, in order to explain how the extension of the grasslands has changed during the past centuries and, thus, which patches are permanent grassland habitats and whether the greatest number of protected plant specimens overlaps with the permanent grasslands.
The Széchenyi Hill (472 m above sea level) belongs to the Buda Hills (top peak 529 m a.s.l.). The study area is situated in the central part and southern slopes of the Széchenyi Hill and mainly covered by grasslands, although our investigations included the surrounding forested habitats as well (Figures
The climate is moderately cool and moderately dry. Due to rainfall distribution, it exhibits a submediterranean character. The hill occupies a transitional position between lowlands and mountains, due to the closeness of the Great Plain and the Danube. Sunny hours reach 1930 per year. Its climate is colder than the average in Budapest, with 8.7 °C annual mean temperature. Winter temperature inversion is a frequent phenomenon here: unclouded, sunny hilltops are even 10 °C warmer than valleys and lowlands in the city. Annual rainfall exceeds 650–700 mm, the most during early summer, the least around late winter. Snow cover lasts for 50 to 55 days. Rendzina soil is dominant on the surface. There are no springs on the Széchenyi Hill (
According to the first written documents, which date back to the 12th century, wine cultivation had started after deforestation. Wine production slightly decreased during the Ottoman invasion and flourished again in the 18th century, but was ended by the phylloxera infestation (late 19th c.). Cottages and chalets replaced the wine plantations (
The process of urban citizens settling in the surroundings during the 19th century encouraged the development of public transportation. A cog-wheel railway has been running from the city-centre up to the Széchenyi Hill since 1890, giving opportunity for the development of a new district, increasing population and growing the number of tourists. New forests were planted (partly of adventive trees), recreational sites were built and touristic routes were designated. Even ski tourism has flourished after 1920 on the hill. Ten tourist hotels were built in the vicinity between 1939 and 1943, some of them at the border of the valuable grasslands. The Hungarian Golf Club was launched here in 1910, with a high-standard golfcourse and fairways which was declared the second most beautiful in Europe by a British golf magazine (
Official nature protection was launched in 1978 by the Buda Landscape Park, which surrounds Budapest from the north-west. Since Hungary’s EU-accession (2004), the study area is also covered by the Natura 2000 ecological network.
Original Holocene vegetation of the area has evolved during the past 10 to 12 thousand years, with relict species remaining in forests and rock grasslands. Besides the climate, anthropogenic activities played a significant role. Original, ancient vegetation was probably intact until the Roman imperial age. The greatest changes have occurred since the mid-19th century, giving home to cultivated plants and weeds (
High plant diversity of the Buda Hills is a consequence of its geographical situation (mix of plain, lowland, hillside), various geomorphology and micro-climatic conditions. It belongs to the Pilisense floristic district within the Bakonyicum floristic sector (part of the Pannonicum floristic region) (
During his floristical studies in 1818, József Sadler recognised that Budapest hosts several rare species and diverse habitats. Vince Borbás stated in 1879 that the vegetation of Budapest significantly differs from the Central European vegetation due to southern and eastern floristical elements. He mentions Anthericum liliago, Amygdalus nana, Coronilla coronata, Iris pumila and Lathyrus pallescens from the Széchenyi Hill (
The study area was designated based on satellite photos and detailed field surveys (Figure
Investigations were undertaken in 2015 and 2016, every 2 to 4 weeks during the vegetation period. The central grassland designated for systematic research covers 8.5 hectare. The surrounding low woods, which were designated based on satellite photos and cover 77.5 ha, was observed occasionally, but is also important for historical reconstructions. We strived to soundly rake over the whole area (with ‘rambling method’) during every visit and recorded the GPS coordinates in case of protected plants; while the other (non-protected) species were listed.
Plants were determined with the help of the determination book of
Besides archive literature, our bases for the landscape history research were military maps and aerial photos, online maps of the mapire.eu and Google Earth and recent online aerial photographs from the Department of Geodesy, Remote Sensing and Land Offices, Hungary (for the list of sources, see Table
In order to answer the research question how the extension of the grasslands has changed during the past centuries and, thus, which patches are permanent grassland habitats, we impounded those areas that are indicated on the map as (or seem to be) grasslands and worked with the profile of the polygons generated by this method. In order to minimise the errors that emerge from inaccuracy, we marked a buffer zone around the designated grasslands in line with the inaccuracy rate of the map (10, 15 and 25 m). These are just approximate data, presumed on the basis of the deviation of georeferenced points from their real location and the distances between the fitting of the segments.
We found 29 protected (one of them is Natura 2000 Annex species) and 1 strictly protected plant species in the grasslands and forests of the studied area (Table
Protected plant species found on the Széchenyi Hill, Budapest (strictly protected species is indicated with an asterisk; Natura 2000 Annex species in bold).
Scientific name | Minimum number of stands |
---|---|
Aconitum vulparia | 160 |
Adonis vernalis | 274 |
Allium sphaerocephalon | 609 |
Amygdalus nana | 30 |
Anemone sylvestris | 15 |
Aster amellus | 40 |
Asyneuma canescens | 220 |
Centaurea scabiosa subsp. sadleriana | 3280 |
Centaurea triumfettii | 87 |
Cephalanthera damasonium | 27 |
Convolvulus cantabrica | 78 |
Coronilla coronata | 165 |
Crepis nicaeensis | 29 |
Dictamnus albus | 1072 |
Erysimum odoratum | 442 |
Iris pumila | 903 |
Iris variegata | 6 |
Jurinea mollis | 246 |
Lathyrus pallescens* | 163 |
Limodorum abortivum | 91 |
Linum flavum | 12 |
Linum tenuifolium | 327 |
Lychnis coronaria | 49 |
Orchis purpurea | 28 |
Phlomis tuberosa | 21 |
Polygala major | 495 |
Pulsatilla grandis | 846 |
Scorzonera purpurea | 60 |
Sorbus danubialis | 8 |
Vinca herbacea | 1952 |
SUM | 11 735 |
Adventive elements (and amongst them, invasive alien species) are rare in the area, despite the fact that human population density surrounding protected areas is a significant and strong predictor of numbers of alien and invasive species (
Changes in the extension of grasslands on the Széchenyi Hill between 1783 and 2016 vary from 6.7 ha to 21.5 ha (Table
Year | Source of data | Area of grassland (m2) |
---|---|---|
1783 | First Military Survey Map | 118273 |
1861 | Second Military Survey Map | 153079 |
1873 | Cadastre Maps of Buda | 214520 |
1882 | Third Military Survey Map | 213585 |
1923 | Renewed Third Military Survey Map | 206760 |
1955 | Aerial photograph of the Military History Map Archives | 165728 |
1959 | Renwed Gauss-Krüger projection map | 127045 |
1978 | Aerial photograph of the Military History Map Archives | 108172 |
1987 | Aerial photograph of the Military History Map Archives | 106315 |
2004 | Google Earth satellite image | 81366 |
2016 | Google Earth satellite image | 67773 |
Creation of the Children’s (that time: Pioneers’) Railway and the national television broadcasting tower during the 1950s caused a massive fall in grasslands, followed by a slighter decrease until the change of political regime (1989) due to slow scrub encroachment and creation of military bases. A possible reason for this fall-off might be the declaration of the Buda Landscape park in 1978, covering also the Széchenyi Hill.
The past three decades showed another massive fall in the extension of grasslands, due to scrub encroachment and re-forestation caused by the abandonment of traditional management (but no data are available for previous management forms) (Figure
Changes in the extension of grasslands on the Széchenyi Hill (Budapest) from 1783 till 2016.
Permanent grasslands, i. e. those areas that have constantly been covered by grasslands (instead of forests) during the past 235 years on the basis of a cutting of historical maps, aerial photographs and satellite images, are presented in Figure
The total area of permanent grasslands since 1783 to date is 24,056 m2, while the same data since 1861 is 54,128 m2, dominated by southern slope steppe grasslands of rocky weak soils in both cases. The greatest number of protected plant specimens per area unit can be found on those patches that have constantly been grasslands since 1783 to date. Contrarily, the cutting of grasslands from 1861 to date contains only half of their number per area unit. A possible reason for this is that the newer grasslands cover mainly those areas that previously have been used for golf purposes or are situated in the central part of the current lawn and, thus, are affected by heavy trampling (Table
Rate of protected plant species on permanent (and total) grassland areas of the Széchenyi Hill.
Studied area | Species number | Flowering stem | Number of stands | Area (m2) | Ratio of flowering stem / area |
---|---|---|---|---|---|
1783 – 2016 cutting | 22 | 15863 | 5117 | 24056 | 0.659 |
1861 – 2016 cutting | 21 | 18834 | 6079 | 54128 | 0.348 |
Grassland in 2016 | 21 | 29997 | 10426 | 67773 | 0.443 |
The highest number of protected plant species, as well as the highest number of their stands, was found in the permanent grasslands (Figure
Although the studied area belongs to the Buda Landscape Park, its real protection and conservation is complicated, since touristic routes lead through and is easily reachable, even by public transport. Besides urbanisation processes (i.e. expansion of built-up areas), the heavy load of tourism (especially on non-designated routes), airsoft races, some illegal shelters for homeless people and game damage (recent study from an adjacent area by
Lack of information boards or fences refers to undesirably little attention being paid by nature conservation authorities. A key challenge for preserving biodiversity is balancing human perceptions, needs and use with ecological requirements (
Taking into account that only 5% of the European Union territory was classified by the European Commission as natural (
Main data of protected plant species found on the Széchenyi Hill, Budapest
Data type: (measurement/occurrence/multimedia/etc.)
Explanation note: Value in Euro is based on the relevant law that determines it in Hungarian Forint.