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Summary: • Specific leaf area (leaf area to dry mass ratio), leaf dry matter content (leaf dry mass to saturated fresh mass ratio) and leaf nitrogen concentration (LNC) have been proposed as indicators of plant resource use in data bases of plant functional traits.• We tested whether species ranking based on these traits was repeatable by studying spatio‐temporal variations in specific leaf area and leaf dry matter content of water‐saturated leaves (SLASAT and LDMCSAT), as well as in LNC, for 57 herbaceous and woody species (or subsets thereof) growing under the Mediterranean climate of southern France.• Interseason and intersite variations were more pronounced than interannual variations, but species ranking for a given trait remained mostly consistent in space and time. Classifications based on LDMCSAT were generally more repeatable across years and sites, whereas those based on SLASAT were more stable over seasons. LNC usually gave the least repeatable classifications.• Species rankings were not completely similar for the three traits. Discussion of reproducibility, ease of trait measurement, as well as trait–function relationships led us to propose that measurements of the leaf traits, SLASAT and/or LDMCSAT, were the most suitable in large screening programmes. [ABSTRACT FROM AUTHOR]

Summary • Specific leaf area (leaf area to dry mass ratio), leaf dry matter content (leaf dry mass to saturated fresh mass ratio) and leaf nitrogen concentration (LNC) have been proposed as indicators of plant resource use in data bases of plant functional traits. • We tested whether species ranking based on these traits was repeatable by studying spatio-temporal variations in specific leaf area and leaf dry matter content of water-saturated leaves (SLASAT and LDMCSAT), as well as in LNC, for 57 herbaceous and woody species (or subsets thereof) growing under the Mediterranean climate of southern France. • Interseason and intersite variations were more pronounced than interannual variations, but species ranking for a given trait remained mostly consistent in space and time. Classifications based on LDMCSAT were generally more repeatable across years and sites, whereas those based on SLASAT were more stable over seasons. LNC usually gave the least repeatable classifications. • Species rankings were not completely similar for the three traits. Discussion of reproducibility, ease of trait measurement, as well as trait–function relationships led us to propose that measurements of the leaf traits, SLASAT and/or LDMCSAT, were the most suitable in large screening programmes. [ABSTRACT FROM AUTHOR]

• The land abandonment changes the ecosystem functions. • The major changes in ecosystem occurs the first two decades since abandonment. • Soil C and N contents and biological activity increase along chronosequence. • Grassland composition determines soil microbial activity. Euro-Mediterranean countries have undergone radical changes in their traditional landscapes due to the abandonment of rural areas. Natural vegetation rapidly colonizes abandoned lands and cause changes in ecosystem functioning. Our main objective was to study how time since abandonment of vineyards influences the physical, chemical and biological properties of the soil and the vegetation composition and cover. In 2016, we selected a chronosequence of six abandoned vineyards (1, 3, 7, 11, 25 and 40 years), an active vineyard, and a plot of land that has not been used as a vineyard for at least the last 60 years. Soil physical-chemical variables, including the organic matter fractions and available nutrients, were analysed. To observe the variation in the biochemical properties of the soils, the activities of 11 enzymes were determined, relating to the main macronutrient cycles: carbon (C), nitrogen (N), phosphorous (P) and sulphur (S) cycling. Three sites (1 m2) were randomly established on each plot within the area occupied by annual grasslands, and species cover was estimated in order to obtain the species density and cover of plant functional traits. Our results showed that the abandonment caused major changes in the functioning of the ecosystems. Secondary succession in abandoned vineyards was characterized by a significant increase in plant species density and by changes in the composition of the annual grasslands, from an early brassicaceous community to a late cistaceous community. This was accompanied by an increase in soil TOC (0.38–1.78%) and TN (0.14 to 0.26 %) content, and the activity of most enzymes. These changes occurred more rapidly during the first two decades after abadonment. [ABSTRACT FROM AUTHOR]