@article{AnsahAbuKleemannetal.2022, author = {Ansah, Christabel Edena and Abu, Itohan-Osa and Kleemann, Janina and Mahmoud, Mahmoud Ibrahim and Thiel, Michael}, title = {Environmental contamination of a biodiversity hotspot — action needed for nature conservation in the Niger Delta, Nigeria}, series = {Sustainability}, volume = {14}, journal = {Sustainability}, number = {21}, issn = {2071-1050}, doi = {10.3390/su142114256}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297214}, year = {2022}, abstract = {The Niger Delta belongs to the largest swamp and mangrove forests in the world hosting many endemic and endangered species. Therefore, its conservation should be of highest priority. However, the Niger Delta is confronted with overexploitation, deforestation and pollution to a large extent. In particular, oil spills threaten the biodiversity, ecosystem services, and local people. Remote sensing can support the detection of spills and their potential impact when accessibility on site is difficult. We tested different vegetation indices to assess the impact of oil spills on the land cover as well as to detect accumulations (hotspots) of oil spills. We further identified which species, land cover types, and protected areas could be threatened in the Niger Delta due to oil spills. The results showed that the Enhanced Vegetation Index, the Normalized Difference Vegetation Index, and the Soil Adjusted Vegetation Index were more sensitive to the effects of oil spills on different vegetation cover than other tested vegetation indices. Forest cover was the most affected land-cover type and oil spills also occurred in protected areas. Threatened species are inhabiting the Niger Delta Swamp Forest and the Central African Mangroves that were mainly affected by oil spills and, therefore, strong conservation measures are needed even though security issues hamper the monitoring and control.}, language = {en} } @phdthesis{Kortmann2022, author = {Kortmann, Mareike}, title = {Biodiversity and recreation - Optimizing tourism and forest management in forests affected by bark beetles}, doi = {10.25972/OPUS-24031}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-240317}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2022}, abstract = {Forests are multi-functional system, which have to fulfil different objectives at the same time. The main functions include the production of wood, storage of carbon, the promotion of biological diversity and the provision of recreational space. Yet, global forests are affected by large and intense natural disturbances, like bark beetle infestations. While natural disturbances threaten wood production and are perceived as 'catastrophe' diminishing recreational value, biodiversity can benefit from the disturbance-induced changes in forest structures. This trade-off poses a dilemma to managers of bark beetle affected stands, particularly in protected areas designated to both nature conservation and recreation. Forest landscapes need a sustainable management concept aligning these different objectives. In order to support this goal with scientific knowledge, the aim of this work is to analyse ecological and social effects along a gradient of different disturbance severities. In this context, I studied the effects of a disturbance severity gradient on the diversity of different taxonomic groups including vascular plants, mosses, lichens, fungi, arthropods and birds in five national parks in Central Europe. To analyse the recreational value of the landscape I conducted visitor surveys in the same study areas in which the biodiversity surveys were performed. To analyse possible psychological or demographic effects on preferences for certain disturbance intensities, an additional online survey was carried out.}, subject = {Borkenk{\"a}fer}, language = {en} }