Distribution and Turnover of Organic Matter and Minerals in a Shore Meadow Ecosystem. Studies in the Ecology of Baltic Sea-Shore Meadows IV

A Juncus gerardi ecosystem in a sea-shore meadow, 125 km SSW Stockholm, was studied with respect to distribution and above ground turnover of organic matter and elements and to primary production. Organic dry matter per sq.m was 6,500-7,000 g humus, 4,200 g below ground biomass + litter, 460 g above ground litter and 160 g maximum above ground biomass. Above ground production was 230 g and below ground production approximately 600 g in a year; 120 g above ground biomass, 230 g above ground litter and approximately 600 g below ground biomass + litter were decomposed. Above ground turnover of elements is discussed. Retention in current litter, measured as per cent of total uptake during a year was K 6, Cl11, Na 16, Mn 20, P 26, S 27, N 38, Mg 39, Cu 45, Ca 52, Zn 53, Si 68, Ni 88, Pb 100 and Fe 100 per cent. Differences in uptake of elements between species are illustrated and discussed, as well as retention in and release from above ground litter. The turnover measurements are based on a detailed study of soil chemistry and ecosystem structure. The different soil and plant chemical methods used are described.