Thematic Imbalance in Mediterranean Climate Adaptation Research: A Systematic Review of Planning-Oriented Literature, 2015–2024

The Mediterranean Basin ranks among the region’s most vulnerable to climate change, yet little evidence exists as to whether the scientific literature emphasises strategic planning or operational implementation. This study measures the thematic distribution of adaptation strategies in the Mediterranean adaptation literature and identifies which categories of measures remain comparatively under-researched. A systematic review following PRISMA 2020 was conducted on peer-reviewed articles indexed in the Web of Science Core Collection and published between 2015 and 2024, retrieved through a thematic query built on regional and landscape planning vocabulary. Of 89 articles retained in the qualitative synthesis, 64 reported at least one codable adaptation measure and entered the quantitative analysis, yielding 123 coded occurrences across twelve thematic categories; the remaining 25 returned a null coding vector. Chi-square goodness-of-fit testing against a maximum-entropy benchmark, with residuals corrected for article-level dependence by cluster bootstrap and for multiplicity by the Benjamini–Hochberg procedure, shows an uneven distribution (χ2 (11, N = 123) = 56.02, p < 0.001; Cramér’s V = 0.20; Pielou’s evenness J = 0.90). Sustainable development and adaptation policy are over-represented; green spaces, cultivation and hydrological interventions are under-represented. An article-level analysis of register co-occurrence finds no segregation between policy-oriented and technical categories: 34.4% of coded articles engage both registers, and the two are statistically independent across the corpus (odds ratio 2.02, p = 0.17). The imbalance is therefore one of volume rather than of community structure. Because the unit of observation is the published article rather than the implemented intervention, and because the corpus is restricted to planning-oriented, English-language, indexed literature dominated by northern-rim EU member states, these findings characterise the orientation of a defined body of literature and cannot establish a gap in adaptation practice. The study provides a reproducible method for measuring thematic emphasis and an empirical basis for identifying under-researched categories of operational adaptation measures.