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Abstract The aim of this study is to propose a new system for ranking models' performance. The system is based on the standardized Ranking Performance Index (sRPI), which combines the results of any number and type of criteria from different simulation scenarios. The sRPI ranges between 0 and 1 (1 for the best and 0 for the worst performing model) based on the relative distance of models' accuracy. The sRPI is also combined with an additional index called RCI (Ranking Criteria Index) that identifies which criteria are the most and the least representative for a specific dataset/scenario. The presentation of sRPI methodology is performed comparing ten reference evapotranspiration models using a large list of statistical criteria for both daily and monthly steps. The sRPI methodology could significantly reduce the complexity to evaluate models' performance based on multiple scenarios and can identify the most descriptive criteria reducing their overuse in modelling studies. Highlights • A new method for ranking models' performance is proposed. • The method combines any number of statistical criteria and simulation scenarios. • The method ranks the models based on their relative distance. • The method also identifies the most descriptive criteria for a specific dataset. [ABSTRACT FROM AUTHOR]

Highlights • Soils from marl, serpentine and serpentinized peridotite were used as substrates. • Most foliar nutrients were significantly lower in the serpentinized soil. • Photosynthesis was significantly lower in the serpentinized peridotite soil. • Increased levels of phenols, TFC and FRAP were found in the serpentinized soil. • Differential tolerance to serpentine stress between 'Wonderful' and 'Acco' existed. Abstract It was investigated if differential genotypic tolerance of two pomegranate cultivars ('Wonderful' and 'Acco') to serpentine stress existed. For this purpose, pomegranate plants were grown outdoors, in three soil substrates (from parent material marl, serpentine and serpentinized peridotite). The results indicated that growth, most foliar nutrient concentrations, total chlorophyll content, chlorophyll fluorescence and photosynthetic rate, for both genotypes, were significantly lower in the serpentinized peridotite soil (severe stress). In contrast, higher levels of total phenolics, total flavonoid content (TFC) and FRAP, were found in the serpentinized soil. Lower tolerance index to stress in the serpentinized soil was found for the cultivar 'Acco', than for 'Wonderful'. Overall, the physiological and antioxidant response of 'Acco' was worse, than that of 'Wonderful', under serpentine stress. In conclusion, despite the lower Ni, Cr and Mg accumulation of 'Acco' (compared to 'Wonderful'), its lower tolerance indices in the serpentinized soil probably shows its higher tissue sensibility to serpentine stress. Thus, this genotype should not be preferred for cultivation in soils presenting high degree of serpentinization (excess Mg concentrations). In contrast, from the tolerance indices of both genotypes in the serpentine soil, it is concluded that a mild stress existed in this case. [ABSTRACT FROM AUTHOR]

• A P-fertilization experiment (+P or –P) was conducted in two olive groves. • P fertilization influenced soil properties, P fractions and its mineralization. • Acid and alkaline phosphatase activities were significantly higher in the –P plots. • P fertilization did not significantly influence trees' foliar P nutrition. • It is useless for the olive growers to provide P every year in their groves. Often, from soil and plant tissue analyses, over-sufficient foliar P levels in olive trees, grown under low Olsen P availability, are determined. In order to deepen our knowledge in this topic, a field P fertilization experiment (with or without supply of the fertilizer 0-46-0) with 25-year-old olive trees was conducted, in order to investigate if: i) soil organic P was a sufficient 'pool' to satisfy the P nutritional needs of mature, fully productive, olive trees under low Olsen P availability and sufficient organic matter content, ii) the activities of acid and alkaline phosphatase were enhanced under low Olsen P availability, iii) soil chemical properties were significantly influenced by P fertilization, iv) significant differences in foliar nutrition of olive trees existed between P-fertilized (+P) and unfertilized (-P) trees. Our results indicated that in the -P plots 48 % of the total soil P was in organic fraction, while in the + P ones approximately 23 % of the total P was in organic form. In contrast, Olsen, inorganic and total P fractions were significantly higher in the + P plots. In addition, in the + P plots significantly lower: i) soil Fe, Mn and Zn, and ii) foliar Ca, Mg and Mn concentrations were determined, while, in contrast, iii) higher leaf K concentration was found. Foliar P was not influenced by P fertilization, while at the same time, both the activities of alkaline and acid phosphatase were significantly higher in the –P plots, compared to those received P fertilization. Overall, the kind of management of olive groves (sufficient organic matter levels, with or without inorganic P fertilization inputs) significantly influences P dynamics and modifies its fractions in soils, while it also affects organic P mineralization and supports P nutrition for olive trees. It is believed that these data reveal the crucial role of organic matter to sustain P uptake and contribute towards a sustainable management of olive groves to support and sufficiently satisfy the P nutritional needs of olive trees, by also significantly reducing the unnecessary annual P fertilizer inputs. [ABSTRACT FROM AUTHOR]