An Update
Well, a long time between updates, but life, as often is the case, sets my timetables! My primary focus over these months has been on securing the site access I need to sample at approximately 60 sites plus reference sites and to collect needed equipment.
Unfortunately, my $1500 grant did not come through and I've worked and reworked my budget to be able to purchase the bulk of my supplies with the Experiment.com funds and with a year's worth of Christmas and Birthday gifts from my very generous in-laws :)
I thought it might make the best sense to eliminate or greatly reduce my largest budget item - the Russian peat corer. I found a paper from 1995 describing in detail how an effective sediment corer could be constructed from simple PVC parts available from any hardware store. The corer was later used by a team sampling sediments in mangrove areas in Florida Bay. We constructed a prototype and tested it in the Indian River.
It basically works by vacuum-- sediments and water are forced into the tube when the tube is driven into the sand and the sediments are only released when the vacuum is broken by removing the rubber stopper on the side. At this point, the paper uses what is perhaps my favorite description of sampling technique found anywhere in the literature when it states that the sampler should be inserted with a "sudden jabbing action" and that "some operators claim that a sudden vocal cry similar to that uttered by a karate expert breaking blocks is required."
I'm sure the sampler works well in some applications, but the dense, hard packed sandy bottom sediments proved to be too much for my prototype. Add to that, the presence of several air leaks and my poor rendition of a karate master's cry, and I realized the sampler may be more effort than it was worth.
So, back to the drawing board and I found an excellent and much less expensive sediment corer capable of trapping even wet waterlogged sediments within the corer. It also holds plastic sampling tubes which can be quickly pulled out and capped. This makes it much more feasible to pull even dozens of samples in a day. In case you're interested here is a video describing its use:
Since I'll be in shallow water (the IRL has an average depth of four feet) and only need samples of 50 cm in depth, I've skipped the additional stages of tubing and rods and received my single tube sampler tonight, woo hoo!!!
Extra tubes will allow for the collection of many samples in a single day of field work:
So, I'll be testing it Friday and will try to post an update on how it worked. I'll also detail my efforts on the site access front in a subsequent lab note. In case this one isn't photo heavy enough... a few other supplies I've acquired:
The Oyster all-in-one meter, the pore water sampler, and the densiometer! Not pictured is an underwater camera, a new set of waders, and a kayak for navigating to spoil islands and shorelines where site access may be more difficult. Still needed are the lab furnace, lab plastic or glassware, and the fairly expensive ion meter and Ag+ Sulfide probe.
More soon!!
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