Thread: Weirs Closed
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Old 04-28-2014, 12:24 PM
Smalls Smalls is offline
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Join Date: Dec 2011
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Quote:
Originally Posted by duckman1911 View Post
Hey smalls I can tell you the difference between them grasses. They all spelled different.lmao
Just messin with you man.
I aint got a freaking clue.
lmao. Let me spell the scientific names. That will give you a headache.

I've attached a document that shows some salinity tolerances of various plants. It is based on some older research, but it was some of the first research done on marsh vegetation in Louisiana, and I believe the same study was used to create the first vegetation type maps of Coastal Louisiana. Because this graph shows a range of salinity tolerances, salinities at the higher ends of those bars will produce lethal environments at extended periods.

Oystergrass, or smooth cordgrass, is probably one of the most salt tolerant plants you will find in that marsh. However, it only occurs in the lower salt marsh. It is excluded from higher areas by wiregrass, or marshhay cordgrass. Marshhay cordgrass dominants the high marsh, which is what I would classify most of the cameron-creole as, except for the far east stretches.

The problem that was occurring in the Cameron-Creole leading up to the construction of the weirs was marshhay die-offs due to extended high salinity, but probably more so high water. Marshhay cannot tolerate extended periods of high water, which is why it is restricted to the high marsh. The marshhay was dying from a combination of stressors, but oystergrass could not colonize the areas fast enough. Thus, you had areas converting to open water.

The eastern stretches of that marsh are probably more dominated by bulrushes, cattails, and Sagitarria species, which are on the lower end of salinity tolerances.

I have seen bulrush tolerate salinities of up to 23 ppt, but the grass was dormant and not growing much. Heavy rains the following year resulted in the plants growing considerably.
Attached Files
File Type: pdf Salinity tolerances.pdf (312.4 KB, 37 views)
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