Humans as long-distance dispersers of rural plant communities
2013 (English)In: PLoS ONE, ISSN 1932-6203, Vol. 8, no 5, e62763- p.Article in journal (Refereed) Published
Humans are known for their capacity to disperse organisms long distances. Long-distance dispersal can be important for speciesthreatened by habitat destruction, but research into human-mediated dispersal is often focussed upon few and/or invasive species.Here we use citizen science to identify the capacity for humans to disperse seeds on their clothes and footwear from a knownspecies pool in a valuable habitat, allowing for an assessment of the fraction and types of species dispersed by humans in analternative context. We collected material from volunteers cutting 48 species-rich meadows throughout Sweden. We counted 24354 seeds of 197 species, representing 34% of the available species pool, including several rare and protected species. However, 71species (36%) are considered invasive elsewhere in the world. Trait analysis showed that seeds with hooks or other appendageswere more likely to be dispersed by humans, as well as those with a persistent seed bank. More activity in a meadow resulted inmore dispersal, both in terms of species and representation of the source communities. Average potential dispersal distances weremeasured at 13 km. We consider humans capable seed dispersers, transporting a significant proportion of the plant communities inwhich they are active, just like more traditional vectors such as livestock. When rural populations were larger, people might havebeen regular and effective seed dispersers, and the net rural-urban migration resulting in a reduction in humans in the landscapemay have exacerbated the dispersal failure evident in declining plant populations today. With the fragmentation of habitat andchanges in land use resulting from agricultural change, and the increased mobility of humans worldwide, the dispersal role ofhumans may have shifted from providers of regular local and landscape dispersal to providers of much rarer long-distance andregional dispersal, and international invasion.
Place, publisher, year, edition, pages
2013. Vol. 8, no 5, e62763- p.
Natural Sciences Engineering and Technology
IdentifiersURN: urn:nbn:se:su:diva-89134DOI: 10.1371/journal.pone.0062763ISI: 000321200500037OAI: oai:DiVA.org:su-89134DiVA: diva2:615900