Abstract
Este artículo contiene 7 páginas, 5 figuras.
extent and seasonality of nutrient limitation of Posidonia oceanica (L.) Delile in the
Costa Brava littoral (NW Mediterranean) in 5 meadows was investigated by means of repeated nutrient
additions along a year cycle. Nutrient additions had a modest effect on leaf growth. The response
to fertilization varied considerably among meadows, with those meadows consistently maintaining low
(300 PM dissolved inorganic nitrogen and 9 pM soluble reactive phosphorus) dissolved inorganic nutrient
concentrations in sediment pore waters showing the greatest response to fertlhzation. The seasonality
of the growth response to fertilization was consistent with calculated nutrient deficiencies, which
were greatest in late spring and summer. Nutrient deficiency was alleviated in the fall, partially due to
reduced growth, but also to nutrient reclamation from old leaves, wh~ch represented 20% and 18% of
the annual nitrogen and phosphorus incorporation, respectively. The relative deficiency of nitrogen
and phosphorus differed among sites, with the highest response found in P-deficient meadows Nutnent
limitation of p oceanica meadows was greatest in late spring and summer, but differed greatly in
magnitude and nature (nitrogen vs phosphorus) depending on local nutrient regimes.
This work was supported by the grant STEP-0063-C of the ECC.
Peer reviewed