This study was conducted at the Institute of Arid Regions of Gabes in Tunisia. Three plots were left as controls and received no input, three plots were amended with cattle manure with a dose equivalent to 37.5 t/ha, and nine plots were amended with phosphogypsum in three doses (12.5 t/ha, 25 t/ha, and 50 t/ha), with three repetitions for each dose. A pot test to determine the germination index and radioactivity analysis was carried out in the laboratory. The results showed that organic manure amendments and phosphogypsum improved the germination rate of the different crops (jute mallow, turnip, and oat) compared with the control. At the same time, the 50 t/ha dose had the highest germination rate. An increase in yield of all crops during the whole duration of the experiment was observed for the soil amended by phosphogypsum. The best yield was recorded when the highest dose of phosphogypsum was applied. The cadmium level in plants of the two applied amendments was variable but still below the toxicity threshold (7 ppm). The values recorded following the analysis of the phosphogypsum radioactivity showed that the mean value of Ra-226 equals 214.45 Bq/kg, which is below the limit announced by the EPA (Environmental Protection Agency). The radioactivity results from the control soil samples showed the presence of natural radioactivity. Samples of phosphogypsum-amended soil and plants grown in these soils have radioactivity values that are still lower than those announced by the EPA. The novelty aspect of this study is the application of phosphogypsum in different crops during two consecutive years in degraded-soil areas of Tunisia, in addition to the study of different aspects of phosphogypsum reuse in agriculture as a promising strategy for a sustainable environment.

Feeding nine billion people by 2050 will be a challenge due to climate change. There is a significant portion of abandoned and unused marginal lands across the nation and in the Puglia region, in Southern Italy. Innovative techniques and practices in the frame of climate-smart agriculture can help rehabilitate marginal lands into productive and profitable areas. The objective of this study was to systematically review the literature on marginal areas in Puglia, responding to the lack of information in this context and evaluate their revitalization potential. We systematically reviewed the literature on unused/marginal areas and identified related studies dealing with different types of marginal areas and their potential for sustainable rural development. Marginal areas in Puglia represent a range of historical rural landscapes that support biodiversity, the economy, and ecological services. However, the analysis of the current situation in Puglia’s marginal areas indicates a lack of infrastructure and scarce resources, which led to land abandonment and the migration of local residents, resulting in the deterioration of the ecological system. Therefore, establishing a sustainable policy is crucial for preserving the local heritage and economy of the region. However, policymakers should carefully study the challenges and opportunities arising from local contexts before embarking on ambitious place-based innovation strategies. The analysis indicates that both biophysical and socio-economic factors are strategic elements for improving the revitalization potential of marginal areas for sustainable development. This review provides useful information regarding the revitalization potential of marginal areas for food, feed, and non-food production, which is crucial in the implementation of a sustainable development strategy for rural communities in Puglia but can also be applied to similar areas in other countries. However, the success of the sustainable development strategy in Puglia’s marginal areas should consider the vital function of farmers’ self-organization and social capital as key factors in the adoption of agricultural innovations for the revitalization of these areas.