ABOVEGROUND PLANT-PRODUCTION AND NUTRIENT CONTENT OF THE VEGETATION IN 6 PEATLANDS IN ALBERTA, CANADA

We examined the effects of water level, surface water chemistry, and c limatic parameters on aboveground primary plant production, and the ti ssue nutrient concentrations in the dominant herb species in a bog, th ree fens, and two marshes. In the fens, total NPP correlated best with NO3- and total phosphorus surface water concentrations in 1993 and 19 94. Total NPP in the marshes correlated best with alkalinity in 1993, and with soluble reactive phosphorus in 1994. Climatic parameters, suc h as mean annual growing season temperature, growing degree days, and precipitation, had the most notable effect on moss growth, whereas shr ub and herb production correlated significantly with the water level r elative to the moss surface. Herb production correlated positively and shrub production correlated negatively with the water level relative to the moss surface. Tissue nutrient concentrations of carbon (C), nit rogen (N), and total phosphorus (TP), and the C:N quotient in Carex la siocarpa exhibited similar trends in the fens and the marshes. Carbon tissue concentrations in C. lasiocarpa remained unchanged, whereas N a nd TP tissue levels decreased throughout the growing season. In the si te with the highest NPP and presumably the highest stand density, C. l asiocarpa exhibited the highest tissue N and TP levels. Furthermore, T P tissue concentrations in C. lasiocarpa were substantially higher in the marshes than in the fens. Tissue nutrient concentrations in Erioph orum vaginatum in the bog showed variable response patterns. N tissue levels increased, whereas tissue TP concentrations decreased from late June to late August. In the bog, E. vaginatum exhibited similar tissu e TP levels to C. lasiocarpa in the fens; however, they were both subs tantially lower than those found in C. lasiocarpa from the marshes.