Fig. 4

Results of water retention and moisture uptake assays by a sandy soil treated with a BS/BE solution, Triton X-100 or tap water. a Trend of water content during the first cycle of irrigation; b results of water retention assay recorded after 12.5 h of the onset of the second irrigation. Analyses of variance performed on water content after 12.5, 14, 15, 16 and 17 h (ANOVA 12.5 h to ANOVA 17 h), showing statistically significant differences among the samples (ANOVA 12.5 h: p < 0.0001, F = 139.41, df = 4; ANOVA 14 h: p < 0.0001, F = 138.19, df = 4; ANOVA 15 h: p < 0.0001, F = 127.16, df = 4; ANOVA 16 h: p < 0.0001, F = 72.06, df = 4; ANOVA 17 h: p < 0.0001, F = 17.80, df = 4; ANOVA 18 h: p = 0.15, F = 2.00, df = 4). According to post–hoc analysis (α = 0.05), means sharing the same letter are not significantly different from each other; c results of moisture uptake assay. ANOVA showing statistically significant differences among the samples (p < 0.0001; F = 148.70; df = 4). According to post–hoc analysis (α = 0.05), means sharing the same letter are not significantly different from each other