Martinez Reyes, Cindy G. (2023) Warming, not acidification, favours survival of non-indigenous over native gammarid species. (Master thesis), Christian-Albrechts-Universität zu Kiel, Kiel, Germany, 44 pp.

Preview

Text Thesis_CMartinez_Final_signed.pdf - Published Version Available under License Creative Commons: Attribution 4.0. Download (1MB) | Preview

Abstract

Anthropogenic activities, including non-indigenous species (NIS) introduction and climate change, among other stressors, have considerably affected ecosystems and socio-economies globally. Despite the widely acknowledged individual roles of NIS and global warming in biodiversity change, predicting the connection between biological invasions and climate change still remains a fundamental challenge and requires urgent attention due to a timely importance for proper conservation management. To improve our understanding on the interaction between climate change and NIS on biological communities, laboratory experiments were conducted to test the temperature and pCO2 tolerance of four gammarid species: two native Baltic Sea species Gammarus locusta and Gammarus salinus), one Ponto‐Caspian NIS (Pontogammarus maeoticus) and one North American NIS (Gammarus tigrinus). The results demonstrated that an increase in pCO2 level was not a significant driver of mortality, neither by itself nor in combination with increased temperature, for any of the tested species. However, temperature was significant, and differentially affected the tested species. The most sensitive was the native G. locusta which experienced 100% mortality at 24 °C. The second native species, G. salinus, performed better than G. locusta, but was still significantly more sensitive to temperature increase than either of the NIS. In contrast, NIS performed better than native species with warming, whereby particularly the Ponto-Caspian P. maeoticus did not demonstrate any difference in its performance between the temperature treatments. With the predicted environmental changes in the Baltic Sea, shifts in distributions of native taxa towards colder areas may be expected, while their niches might be filled by NIS, particularly those from the Ponto- Caspian region. As the chance of impactful NIS arriving increases with the increased number of establishing NIS, the danger of the negative impact connected with the new NIS may rise as well.

Actions (login required)

View Item