Aims Leaf carbon (C), nitrogen (N), and phosphorus (P) concentrations and their stoichiometry can provide a basis for plant nutrient status and element limitation. Our objective was to explore variations of leaf C:N:P stoichiometry in plants of different growth forms.
Methods We analyzed leaf C, N, and P concentrations in three graminoids (Eriophorum vaginatum, Carex globularis, Deyeuxia angustifolia), five deciduous shrubs (Betula fruticosa, Salix myrtilloides, Salix rosmarinifolia, Vaccinium vitis-idaea, Vaccinium uliginosum), and three evergreen shrubs (Ledum palustre, Chamaedaphne calyculata, Rhododendron capitatum) across 18 peatland sites in the Da Hinggan Ling, northeastern China.
Important findings (1) Leaf C, N, and P concentrations were higher, and the leaf C:N, C:P, and N:P values were lower, in deciduous and evergreen shrubs than in graminoids, indicating that plants of different growth forms had different nutrient utilization strategies. Shrubs had higher C, N and P storage and lower N and P use efficiency than graminoids. (2) Leaf N:P values in Deyeuxia angustifolia and R. capitatum were less than 10, and their leaf N concentrations were lower than the global mean leaf N concentration, indicating that those species were limited by N more than other plants. (3) The sampling sites explained 12.8%-40.8% of the variations in leaf C, N, and P stoichiometry, and plant species explained 9.3%-25.5%. (4) Graminoids had greater inter-site coefficient of variance (CV) values in leaf C, N, and P variables than deciduous and evergreen shrubs, indicating greater sensitive to site factors. (4) The inter-species CV values in leaf N were greater in graminoids than in deciduous and evergreen shrubs, and the inter-species CV values in leaf P were greater in deciduous shrubs than in graminoids and evergreen shrubs, indicating greater physiological differentiation in N and P use strategies in graminoids and deciduous shrubs than in evergreen shrubs.