A. Sfriso et A. Marcomini, GROSS PRIMARY PRODUCTION AND NUTRIENT BEHAVIOR IN A SHALLOW COASTAL ENVIRONMENT, Bioresource technology, 47(1), 1994, pp. 59-66
Citations number
38
Categorie Soggetti
Energy & Fuels","Biothechnology & Applied Migrobiology",Agriculture
The estimation of the gross primary production (GPP) through measureme
nts of a conserved element, such us phosphorus (P) in macroalgal bioma
ss, surface sediment and settled particulate material (SPM) is propose
d. The central Venice lagoon is covered by a biomass ranging from 1 to
20 kg m(-2), wet wt, with macroalgae accounting for almost the whole
production. The total phosphorus GPP (P-GPP) was more than sixfold the
P involved in the net primary production (P-NPP). The GPP also provid
ed the fluxes of nutrients at the water-sediment interface and allowed
the estimation of losses of nonconserved elements, such as nitrogen (
N) and carbon (C), by denitrification and respiration-decomposition pr
ocesses, respectively. In the Venice lagoon the Nand C losses were eva
luated to be 51% and 63%, respectively, of the nutrients involved in t
he total GPP. From a comparison of these results with the total nutrie
nt loadings entering the lagoon through external inputs, it was sugges
ted that the sea strongly supported the GPP occurring in the lagoon. T
he release of N from the lagoon to the atmosphere was equivalent to ab
out 4.3 times the N introduced yearly from external inputs.