Nitrogen supply effects on productivity and potential leaf litter decay of Carex species from peatlands differing in nutrient limitation

摘要: We investigated the effect of increased N-supply on productivity and potential litter decay rates Carex species, which are dominant vascular plant species in peatlands Netherlands. hypothesized that: (1) under conditions N-limited growth, will lead to but not affect C:N ratios that litter; (2) P-limited it lower thereby a higher rate litter. These hypotheses were tested by fertilization experiments (addition 10 g N m-2 year-1) growth was P-limited, respectively. effects net C-fixation biomass, uptake, leaf chemistry decay. In peatland, dominated lasiocarpa, there no significant increase biomass upon enhanced N-supply, although N-uptake had significantly compared with unfertilized control. Due N-fertilization ratio decreased significantly. Similarly, produced at end experiment showed decrease N-supply. The litter, measured as CO2-evolution from aerobic conditions, C. acutiformis, increasing whereas significant. both living material dead leaves did change response N-fertilization. affected results agree our hypotheses. This implies atmospheric N-deposition may CO2-sink function peatlands, is dependent nature nutrient limitation. where N-limited, leads an accumulation Under however, C-accumulation decrease, because further increased, amount C lost through decomposition organic matter increased. As most terrestrial ecosystems C-accumulation.