Seasonal Production of the Myriophyllum Component of the Littoral of Lake Wingra, Wisconsin

• Published in: The Journal of ecology 1974-07, Vol.62 (2), p.457-465
• Main Authors: Adams, Michael S., McCracken, Michael D.
• Format: Article
• Language: English
• Subjects: Biomass; Biomass production; Carbon; Glacial lakes; Growing seasons; Lakes; Littoral zones; Macrophytes; Photosynthesis; Productivity
• ISSN: 0022-0477; 1365-2745
• DOI: 10.2307/2258991

The littoral of Lake Wingra is occupied by a plant community dominated by the submergent macrophyte Myriophyllum spicatum L. This study reports the seasonal pattern of ash-free biomass production, photosynthetic capacity (mg C fixed g-1h-1) of terminal portions of stems, productivity (mg C fixed m-2day-1) of stem tips, and calculations of mean and maximum productivity of the Myriophyllum component of the littoral zone community. Spring and autumn peaks in photosynthetic capacity were observed. Depth-integrated maximum seasonal productivity on the date of maximum photosynthetic capacity during 1971 was 10· 8 g C day-1m-2littoral, or 3· 35 g C day-1m-2lake. This is 4· 70 t carbon day-1total lake-1, or 10· 70 t ash-free dry weight. Mean daily total macrophyte net photosynthesis (growing season) for the diurnal periods alone, integrated with depth, was 1· 77 g C day-1m-2littoral ($3\dot 89$g ash-free dry wt day-1m-2littoral). Mean net daily biomass increment to 1 September was 680 mg C day-1m-2littoral. Approximately 1· 6 maximum standing crops were lost through both night-time respiration and sloughing of parts (leaves) by the submergent macrophytes. Total annual production by macrophytes was 117 g C m-2lake surface, higher than that of several other lakes which were compared.