What Makes a Tide? Two Buckets, Tubing, and a Pump

Researchers have somehow managed to replicate the natural ebb and flow of the tide with a few tools from their local home improvement shop.

That's according to a study recently published in the journal Applications in Plant Sciences, which details how inexpensive and controlled microcosm with a simulated tide could help researchers better understand how to preserve and improve declining total marsh plant ecosystems.

"Tidal wetlands are often influenced by many factors, and controlled experiments allow researchers to isolate and untangle the roles of individual variables," Rachel MacTavish, at the Sapelo Island National Estuarine Research Reserve in Georgia, explained in a statement. "I was inspired to construct and test this tidal simulation method as a way to examine the effects of added nutrients and salt in the water on salt marsh plant nutrient uptake."

According to the study, the tidal simulator unit designed by MacTavish and co-author Risa Cohen costs a mere $27 at most, and takes up less than two square feet. Best of all, it's self-contained, not relying on long lines of external plumbing to operate.

To prove the reliability and accuracy of their tidal simulator unit, Cohen and MacTavish compared the growth of the tidal cordgrass Spartina alterniflora in field sites to the growth of the grass in controlled microcosms - complete with their simulated tide.

The results showed no notable difference in the growth of these plants, meaning that the natural conditions were adequately recreated in the lab environment.

The researchers argue that their new and simple tidal simulation system will make the study of tidal effects significantly easier, where the spread of threats to tidal ecosystems - such as oil spills, heavy metal poisoning and acidification - can now be studied in small and contained experiments with accuracy.

"I'm already using [the tidal simulator] in one of my experiments to study the concurrent effects of altered water column ammonium and salinity on S. alterniflora nitrogen uptake," MacTavish said.

She added how other colleagues are using the same systems to look at ways to improve salt marsh restoration strategies.