12 research outputs found
Alkaline phosphatase activity and phosphatase hydrolyzable phosphorus for phytoplankton in hiroshima bay, Japan
The use of surface alkaline phosphatase activity in the seagrass Posidonia oceanica as a biomarker of eutrophication
7 páginas, 4 figuras, 2 tablas.Eutrophication is one of the most relevant man-induced changes occurring in
coastal waters. The identification and assessment of specific responses to eutrophication
in seagrasses can provide a useful tool for the detection of changes in
the water quality in coastal zones, given the wide range of distribution of these
organisms. In this study, we combine a correlational (across-sites comparison)
and a manipulative (fertilization experiment) approach to evaluate the usefulness
and potential of alkaline phosphatase activity (APA) in the endemic Mediterranean
seagrass Posidonia oceanica as an eutrophication biomarker. Our
results showed that APA decreases promptly following nutrient additions, the
response being maintained except during the winter period. APA also varies
across natural meadows under different levels of nutrient discharges at scales
relevant for monitoring purposes. AP activity seems to be an optimal ‘physiological
biomarker’ that responds promptly and reliably to a pulse of eutrophication
exposure. However, other considerations, such as the seasonality (the
response disappears in winter), suggest its use with some caution and, as far as
possible, as a complement of other bio-indicators.This study received financial support from the project
Plan Nacional I + D (REN2002-04020-C02/MAR).Peer reviewe