Over de groei van nonnetjes (Macoma balthica) op het Balgzand
Knol, E. (1983). Over de groei van nonnetjes (Macoma balthica) op het Balgzand. Interne verslagen Nederlands Instituut voor Onderzoek der Zee, 1983(1). NIOZ: Texel. 55 pp.
Part of: Interne verslagen Nederlands Instituut voor Onderzoek der Zee. Nederlands Insituut voor Onderzoek der Zee. , more
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Abstract |
Onset of growth has been studied during a fourteen years sampling program of the Balgzand Macoma balthica population (e.g. BEUKEMA, 1974) .The onset of growth starts in the last week of February for some Macoma. About the middle of March nearly the whole population is growing. Strong winters delay the onset of growth of most Macoma. At the northern transects Macoma is setting on growth earlier because the northern transects are close to the North Sea water inlet, and this water is warmer than the southern transects in winter. During the first half of 1982 the increase of Ashfree Dry weight (a.d.w.), the increase of shell weight and the increase of shell length have been observed at different begin length classes. All three start at the beginning of March. Until spawning especially increase of a.d.w. and shell length are large. After spawning increase of shell weight is large too. At the end of June or at the beginning of July the growth of Macoma stops. |
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