Mervi Orvokki Luoma1, Mariana Tamayo1 and Snorri Sigurðsson2
1Environment and Natural Resources, Faculty of Life and Natural Sciences, University of Iceland, Hringbraut 101, 101 Reykjavík, Iceland
2Department of Environment and Planning, Reykjavík, Iceland
e-mail: email@example.com (Mervi Orvokki Luoma)
Protecting urban biodiversity is a key priority for many cities around the world. However, promoting the success of all biodiversity regardless of origin or characteristics may lead to decline of native species. One invasive alien plant of concern in Reykjavík, Iceland is Anthriscus sylvestris, which has been spreading throughout Iceland. This invasive species often creates monocultures that replace other plant species, enhances soil erosion, and changes landscape aesthetics. In addition, the alien plant Myrrhis odorata, also from the Apiaceae family and with similar plant traits to A. sylvestris, is becoming more prevalent in Reykjavík. We began a study in 2017 to map the distribution of A. sylvestris and M. odorata in four open urban areas in Reykjavík (Laugarnes, Vatnsmýri, Elliðaárdalur, and Ægisíða). The aim of the project was to identify hot spot areas with high abundance of A. sylvestris and M. odorata as they may increase the risk of losing native plant species in those areas. Furthermore, we assessed whether there is an overlap in distribution between A. sylvestris and M. odorata. Surveys were conducted on foot using AllTrailsPro and ArcGIS mobile applications. These mobile applications were used to record the GPS locations of A. sylvestris and M. odorata and draw polygon shapes to indicate their distribution and extent. To date, 158 ha have been surveyed (across all four areas), of which A. sylvestris covered 10% (15.5 ha) of the study areas and was most abundant near pathways, riversides and streams. Anthriscus sylvestris is spreading throughout Reykjavík and is a serious concern in the wildlife nature reserve of Vatnsmýri and the popular outdoor area of Elliðaárdalur. Myrrhis odorata distribution was less common in all study areas except for Laugarnes, where it was double that of A. sylvestris, covering over 8% of the study area (1 ha). In Elliðaárdalur M. odorata was also present, covering approximately 0.5 ha of the area in 2017. In general, the distribution of the two plant species did not overlap. This is the first time that A. sylvestris and M. odorata are mapped in Reykjavík and this work is essential for developing a management plan for these species. Mapping the distribution of alien and invasive species, testing and adopting multi-approach techniques via adaptive management, and conducting long-term monitoring are essential in fostering a functioning, species rich urban ecosystem.