ASSESSMENT OF ADAPTIVE MULTI-PADDOCK GRAZING UNDER MEDITERRANEAN AGRO-SILVOPASTORAL SYSTEMS

Agroforestry activities such as silvopastoral systems can represent an optimal integration between the need for land use and the conservation of ecosystem services. Nevertheless, innovative practices and tools are needed to face the loss of profitability of agricultural activities in silvopastoral areas of the Mediterranean basin. Adaptive Multi Paddock (AMP) grazing management is a grazing strategy that combines intensive grazing, rapid rotation of grazing livestock, and managing livestock/grassland with adaptive decision-making. This grazing strategy is typically implemented through a high-intensity rotation of animals on multiple small paddocks to provide periods of short duration followed by adequate grass recovery periods. The AMP grazing system has stimulated long-lasting and still unresolved debates in the bibliography, bringing the generation of different names to the same management. It has been argued that AMP systems can increase productivity in pastures, mainly through the impact of densely grouped animals on primary production. However, the vast majority of experiments do not support the perception that AMP is more effective than continuous grazing. Studies on AMP considering vegetation composition changes, relative frequency and contribution to dry weight of the most desirable and palatable species are not frequent. This thesis aims to reach a deeper understanding of the AMP impacts on Mediterranean silvopastoral systems. In the first chapter, the impacts of the AMP grazing system adoption in a Mediterranean silvopastoral farm were assessed in a two-year field experiment. The second chapter evaluated the large-scale impacts of AMP adoption through a remote sensing approach within Dehesa farms in a study area located in the Southwestern Iberian peninsula. The results from the field study partially confirm that the adoption of the AMP grazing system can improve grassland productivity, as grazing management influenced the total biomass production only in autumn grazing areas. Nevertheless, it emerged that introducing a rotational grazing system in Mediterranean silvopastoral systems can enhance the efficiency of forage resource exploitation. The results from the remote-sensing study partially confirmed the hypothesis that adopting adaptive management can change the patterns of forage availability, as the NDVI response to the AMP grazing system was evident only at the early stages of the growing season. Nevertheless, the overall lower spatial variability of NDVI in AMP than in continuously grazed areas, and the reduced variability after the AMP adoption, can be considered as a reasonable indicator of better exploitation of forage biomass. The results highlighted that the adoption of adaptive grazing management, in a context of climate change, land degradation, rising costs, and loss of competitivity if agricultural activities in marginal and less productive areas, could represent an effective strategy to enhance the efficiency in forage resources exploitation contrasting the overall land degradation.