Cemetery fugitives: the role of the land use of the surroundings of burial places in alien plant species invasions.
Development of human population is linked to drastic transformations of natural habitats, often resulting in significant losses in biodiversity. One element of this land usage which is inextricably linked with human settlement are cemeteries. Numerous species planted in cemeteries are alien, and as a result, cemeteries can act as hubs of alien plant species invasions. The aim of our study was to examine the relation between cemeteries, their surroundings (i.e. the area in the immediate vicinity of the cemetery) and alien plant species occurrence. We hypothesised that highly disturbed land in surrounding of the cemetery provides increased opportunity for alien plant species to invade. We studied 32, cemeteries and their surroundings located in southern Poland. The cemeteries were divided into three groups, based on the land use of their surroundings: highly disturbed, semi-natural, and natural. We found 138 alien plant species present in the studied cemeteries, 43 (31.1%) of which are classified as invasive in Poland. We did not find statistically significant differences in the number of alien plant species present in the cemeteries (between identified groups). However, the analyses showed that the number of alien plant species present both in the cemetery and its surroundings was higher in cemeteries with 'disturbed' surroundings than in cemeteries with 'natural' surroundings. Our study shows that cemeteries can be hubs for alien plant species dispersal. To decrease chance of invasion by alien plant species planted in cemeteries the authorities and managers should seek opportunities to maintain or improve biodiversity and ecosystem functioning of habitats around cemeteries.