Grantee Research Project Results
The Effects of Microalgal Primary Production on the Recolonization of Macrofauna iInto Saltmarsh-Pond MesocosmsEPA Grant Number: U914949
Title: The Effects of Microalgal Primary Production on the Recolonization of Macrofauna iInto Saltmarsh-Pond Mesocosms
Investigators: Stocks, Karen I.
EPA Project Officer: Hahn, Intaek
Project Period: January 1, 1996 through January 1, 1999
Project Amount: $102,000
RFA: STAR Graduate Fellowships (1996) RFA Text | Recipients Lists
Research Category: Fellowship - Oceanography , Fellowship - Aquatic Ecology and Ecosystems , Academic Fellowships
The objective of this research project is to determine the effect of microalgal primary production on the rate and species composition of macrobenthic recolonization into saltmarsh ponds.
Replicated mesocosms mimicking natural ponds (1.5 m diameter, 0.6 m deep) were dug into an intertidal saltmarsh in New Jersey, and were filled with 10 cm of natural sediments in which all macrofauna had been killed. One-half of the ponds were shaded to inhibit photosynthesis. In addition, half way through the experiment, the shading treatment was crossed with an oxygenation treatment in which ponds were bubbled to keep dissolved oxygen levels high. Because oxygen levels in marsh ponds can periodically decrease to levels stressful or fatal to benthic fauna, and because photosynthesis increases oxygen, decreasing microalgal production could affect the benthic animals both by decreasing a food source and by increasing oxygen stress. The oxygenation treatment was designed to differentiate these two effects. The ponds were sampled with cores over two months during the summer, and all colonizing macrofauna were identified and counted.