Seasonal Nitrogen Dynamics of Zostera marina inhabited in Dongdae Bay and Ojiri

Abstract

All seagrass samples were separated into four fractionsnitrogen content in different fractions of Zostera marina. There are temporal variations of shootproduction rates and total nitrogen contents in their different fractions at both study areas. Leafproduction were almost 4 to 5 fold higher in summer than in winter. The irradiance is theprimary factor controlling the leaf production of Zostera marinain both sites although watertemperature also influence its productivity. Nitrogen contents of leaves were overall low insummer than in winter, but nitrogen content of rhizome increased during the summer season. Inaddition, nitrogen contents of new leaves were mostly higher than adult leaves in spite of lowernitrogen content of new and adult leaves in high productivity period. This result suggests thatZostera marinacontent of leaf tissue may reflect nutritional nitrogen availability.