Primary production and the biomass cycle of a shallow Cymodocea nodosa
(Ucria) Ascherson meadow in the lagoon of Venice (Italy-Northern Adri
atic) were measured from February 1993 to February 1994. Leaf growth w
as estimated by the Zieman method; rhizome production was estimated by
marking rhizome terminals. All data showed a clear seasonality. In ge
neral, maximum growth was reached in July. Leaf production (a maximum
of 12.3 g dry weight m(-2) day(-1) in July) and leaf biomass (a maximu
m of 810 g dry weight m(-2)) were much higher than in other Mediterran
ean localities. Cymodocea nodosa contributes significantly in stabiliz
ing lagoon bottom sediments. The percentage of the belowground fractio
n of total biomass varied from 85% in winter to 58% in summer, and max
imum shoot density was 2302 shoots m(-2). (C) 1997 Elsevier Science B.
V.