The impact of climate change on mango cultivation in southern Europe

Abstract

The cultivation of mangoes (Mangifera indica L.) is gaining importance in Europe, especially in Southern regions, due to favourable climatic conditions. With the ongoing climate change, there is a potential for further improvement in these conditions, making southern Europe possibly more suitable for mango cultivation in the future. This study aims to assess the potential future impacts of climate change on mango cultivation suitability in southern Europe, focusing on Spain, Italy, Greece, south of France, Croatia, Montenegro & Albania.

Using Environmental Niche Modelling (ENM), this research integrates correlative and mechanistic approaches to evaluate current and future suitability scenarios. Key environmental variables, such as temperature, degree days, air humidity, cloud cover and soil factors, were analysed using Generalized Linear Models (GLM), Boosted Regression Trees (BRT), and Maximum Entropy Modelling (Maxent) with presence-only, randomly generated pseudo-absence observation data.

The performance of the algorithms was evaluated using metrics such as the Area Under the Receiver Operating Characteristic Curve (AUC) and the True Skill Statistic (TSS). All algorithms demonstrated high accuracy, with AUC values exceeding 0.8, but the difference in TSS values between calibration and validation suggests diminished model performance in new scenarios, highlighting the potential impact of overfitting due to limited observation points, emphasizing the need for cautious interpretation of the results. To ensure robustness and reduce uncertainty, an ensemble approach was adopted, averaging the results from GLM, BRT, and Maxent models.

Results from the mechanistic approach, which incorporates expert knowledge on physiological and morphological data, show a broader potential expansion of suitable areas compared to the correlative approach, which relies on observed relationships between species occurrence and environmental conditions. The mechanistic approach suggests that inland areas, particularly in Spain, might become more suitable due to projected increases in temperature. In contrast, the correlative approach indicates more conservative estimates of suitable areas, highlighting the importance of air humidity and specific microclimatic conditions. An combination of results reveal that while current suitable areas are concentrated along coastal regions of Spain and Italy, future projections extend these areas further inland and into new regions within Greece and Portugal.

The overall results indicate a significant expansion of suitable areas for mango cultivation under future climate scenarios. Both SSP1-2.6, which assumes lower greenhouse gas emissions, and SSP5-8.5, with higher emissions, project growth of suitable areas. However, water stress remains a limiting factor in both scenarios, particularly under SSP5-8.5. A spatial comparison reveal that while current suitable areas are concentrated along coastal regions of Spain and Italy, future projections extend these areas further inland and into new regions within Greece and Portugal. The analysis also highlights the critical role of irrigation and the need for adaptive agricultural practices, including efficient water management and strategic planning, to mitigate the adverse effects of climate change on mango production, as water scarcity remains a major constraint despite favourable temperature trends.

This research contributes to the growing body of knowledge on the impacts of (future) climate change on mango suitability in southern Europe and offers valuable insights for farmers, policymakers, and stakeholders in the agricultural sector. By anticipating changes in suitable cultivation areas, strategies can be developed to sustain and potentially expand mango production in Europe.