Tissue nutrient signatures predict herbaceous-wetland community responses to nutrient availability

An extensive survey of European wetlands was undertaken to compare the impo rtance of growing conditions vs functional characteristics of vegetation in determining N, P and K contents. Stress-tolerator dominated stands (S) had consistently lower nutrient conte nts and higher N : P ratios whereas ruderal-dominated (R) stands displayed the opposite pattern. Competitor (C) and competitor-stress tolerator (CS) s tands were intermediate to R and S. These patterns were mostly preserved after removing covariation between veg etation and environment, thus indicating constitutional differences in nutr ient signatures between functionally differentiated vegetation. C and R sta nds were least likely to be nutrient limited. Half of the S stands were pro bably P-limited but C, CS and R stands rarely or never experienced P limita tion. Inferred colimitation by K was twice as frequent in S stands compared with other vegetation. This study extends the evidence for syndromes of traits closely linked to n utrient use efficiency that increase fitness under particular growing condi tions. It also highlights patterns at a community level across a wide range of wetland types and suggests that tissue nutrient signatures will have di agnostic value in predicting community responses to perturbation in nutrien t availability.