Effects of Nutrient Enrichment and Water Motion on the Coral Pocillopora damicornis

Abstract

Exposure of the hermatypic coral Pocillopora damicornis (Linnaeus)
\nto elevated levels of dissolved inorganic phosphorus did not affect the colony or
\nthe zooxanthellae. Exposure to elevated levels of dissolved inorganic nitrogen
\nand inorganic nitrogen + phosphorus led to an increase in algal density, and as
\na result, to an increase in the chlorophyll concentration. These latter two experimental
\nenrichments slowed skeletal growth rate of the corals, probably because
\nof a decrease in the photosynthetic rate of the algae and perhaps a decrease in
\nthe translocation of photosynthetic products from the algae to the coral. The
\nalgae probably used the photosynthetic energy for their own increased growth.
\nExperimental manipulation of water motion used in these experiments did not
\naffect the coral or the symbiotic algae.