|Factors limiting phytoplankton production in a tropical continental shelf ecosystem|
Burford, M.A.; Rothlisberg, P.C. (1999). Factors limiting phytoplankton production in a tropical continental shelf ecosystem. Est., Coast. and Shelf Sci. 48(5): 541-549
In: Estuarine, Coastal and Shelf Science. Academic Press: London; New York. ISSN 0272-7714, more
|Authors|| || Top |
- Burford, M.A.
- Rothlisberg, P.C.
The effects of light and nutrients on phytoplankton production were examinedduring both the south-east monsoon (winter) and north-west monsoon (summer) inthe northern Gulf of Carpentaria, Australia. Integrated production and chlorophyllvalues were similar between summer and winter in Albatross Bay in the north-eastGulf over 4 years where shallow waters within the coastal boundary layer (<20m)were well-mixed year-round. Integrated production in well-mixed, deeper (>20m)waters of the Gulf was low (winter, 557 plus or minus 351mgCm super(-2)daysuper(-1)) compared with waters which were stratified during the north-westmonsoon (summer, 955 plus or minus 129mgCm super(-2)day super(-1)). Thelower production was due to high turbidity and light attenuation in the watercolumn; coccoliths from algal detritus were the main cause. However, chlorophylla concentrations were higher in winter (32.9 plus or minus 6.4mgm super(-2)) than in summer (16.8 plus or minus 3.4mgm super(-2)). While molar N:P ratios werelow (2.9), which is indicative of nitrogen limitation, nutrient addition andsuper(15)N-nitrogen uptake experiments showed no such limitation. There wasalso little or no indication of silicate or phosphate deficiency. This contrasts withmany other continental shelf systems that are nitrogen-limited. It is concluded thatlight, rather than nutrients, limited phytoplankton production during the south-eastmonsoon in offshore waters.