Bachelorstudiengang Umweltwissenschaften, 66 Seiten (Erst- und Zweitgutachter)

In this study the population of neophytes in the coastal location of Carolinensiel is examined. The aim is to analyze the effect of different types of human utilization, as well as to compare the population of neophytes in Carolinensiel to the population on the East Frisian Islands and discuss possible dispersion from coastal mainland to the islands.

To accomplish this, the results are compared to earlier studies about neophytes in the village Hooksiel (Kröger, 2020), on the highly touristic island Wangerooge (Reiff, 2019) and the uninhabited island Mellum (Wißmann, 2019), which all are located close to the study area. Not the whole study area, but sections of 100-meter length on public streets are examined. In total 157 sections are tested, half of which is selected randomly while the other half is selected by personal preference. Results show 43 different species of neophytes of which eight have invasive potential.

The highest number of different neophytic species appears in residential zones, while touristic and traffic zones show the lowest number. Areas that are used as forest and parks provide only slightly more neophytic species than areas that are used for tourism and traffic or for agriculture. The high number of neophytes in residential zones can most likely be explained by the variety of suitable habitats and frequent planting of neophytes by inhabitants.

In general, human planting plays a major role in neophyte appearance in the study area, as the origin of most of the neophytes with invasive potential probably lies in previous planting. The comparison of the four examined areas indicates few similarities between the sites. Only the four species Medicago sativa agg., Oenothera spp. Rosa rugosa and Senecio inaequidens are present in every location. The closest similarities, however, can be seen between the sites Carolinensiel, Hooksiel and Wangerooge, while Mellum clearly differs. The reason for this difference can mainly be explained by the absence of four species, which are all present in the other sites.

A possible explanation for that might be the fact, that these species are dependent on humans either for long distance dispersal or for human-made habitats. Therefore, the extremely low presence of humans on Mellum might be the main reason for the neophytes’ absence. Wangerooge on the other hand, shows a big variety of neophytes. Thus, the natural barrier of the island does not seem to prevent the dispersion of neophytes. Much more than this barrier, the intensity and modality of human utilization might be the limiting factor for the appearance of many neophytes.

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Julia Sindermann - Neophytenerfassung in der Stadt Wilhelmshaven- Das Vorkommen und die Verbreitung von Neophyten im städtischen Raum am Beispiel einer Küstenstadt