Master Thesis

Assessing the Endemic Flora in La Palma’s Abandoned Agricultural Lands to Navigate Agricultural Transitions

Anna Handte-Reinecker (01/2024-10/2024)

Support: Carl Beierkuhnlein, Anna Walentowitz

Biodiversity loss poses a global crisis, particularly on islands, which face unique challenges reconciling conservation with agricultural demands amid limited resources, population growth, habitat loss, low food self-sufficiency, and climate change. The complexity of these demands is compounded by land-use changes, which threaten island biodiversity and are often driven by agriculture. On many islands, the economic transition away from agriculture has led to the abandonment of agricultural lands and dependence on food imports. On the island of La Palma, Canary Islands, officials aim to ensure the sustainability of local food production systems and increase self-sufficiency by transforming over half of the abandoned agricultural land into organic farmlands by 2030. This thesis explores the importance of abandoned agricultural land for endemic flora on La Palma to assess the potential impacts of re-cultivation on the Island. Using data from the Government of the Canary Islands and the University of Bayreuth’s Biogeography Department, the distribution of endemic species across various land-use categories was analyzed, comparing abandoned and agricultural lands near forest and non-forest ecosystems. Analysis revealed abandoned lands harbor significantly more endemic flora than agricultural fields, with significant results of Multi-Island Endemics (MIEs) dominance over Single Island Endemics (SIEs) on abandoned fields near forested and non-forested ecosystems. Although there are more MIEs than SIEs a greater proportion of all known SIEs are found near forested areas, compared to the proportion of all known MIEs. Geographical location, elevation, and life forms offer further insights into the endemic species distributions on La Palma, necessitating careful consideration in land management and conservation strategies. These results suggest that reactivating abandoned lands for agriculture could negatively impact endemic species that reside in these areas by removing a habitat that hosts various endemics. While more MIEs could be affected per plot, a higher proportion of the island's SIEs than MIEs may be disrupted near forest ecosystems. The broader implications of this research emphasize the necessity of integrating ecosystem preservation with agricultural practices to address the global challenges of biodiversity loss, food security, and climate change. Greater consideration of conservation and agricultural requirements may help create land-use policies that can improve the resilience of island ecosystems and support sustainable development goals.