Figure 4

Foliar δ¹⁵N of native and alien Cerrado plants in a mesocosm experiment. Foliar samples were collected at harvest (t = 7 weeks) of two alien grasses (Melinis minutiflora—orange circles) and Urochloa decumbens—orange triangles), two native Cerrado grasses (Saccharum asperum—blue circles and Setaria poiretiana—blue triangles) and a native leguminous forb (Stylosanthes guianensis—grey losanges) growing in monocultures or in mixtures of two or three species. Symbols show mean values (+ SD) of 9–10 replicates for all species in panels a and b, and for M. minutiflora, U. decumbens and S. guianensis in panel (c). For panel (c) S. asperum and S. poiretiana had 2–8 and 6–9 replicates, respectively. Only samples from the unfertilized mesocosms were analyzed on foliar δ¹⁵N. Symbols placed in the same vertical line in panels (b) and (c) show values from a species combination treatment. Different letters indicate significant differences at the p < 0.05 level (Tukey contrasts after Anova Type II).