A few weeks ago I posted a question and several people asked me to post the replies. The question was:
I'm looking for a way to automatically measure the salinity of the water in an estuary for a couple of months this fall. I can get to the site every week or so, so I don't need massive data storage. Hourly measurements would be fine, and I'd like to measure salinity at several different sites that are no more than 30 meters from each other. doesn't look like iButtons or Hobos do this. anyone else ever faced and solved this problem? The replies were: 1. Try a manta (although they're not cheap) http://www.eurekaenvironmental.com/manta/overview.htm 2. You might want to check out Starr-Oddi, they have small automatic salinity data loggers that would work well for you you have described. However, I think they can be pricey. http://www.star-oddi.com/ 3. I used to use YSI and Hydrolab CTD's to take measurements in the Chesapeake Bay. I think that those companies manufacture products that you can deploy for periods of time and occasionally pull up to download the data--the memory capacity varies. 4. We have been using Starr-Oddi units (http://www.star-oddi.com/) in manatee tags to record salinity and water temp. Somewhat expensive (~$1200 per unit) but gets the job done. 5. I would suggest using salinity measuring devices connected to a small laptop computer with the correct adapter. You could probably keep the computer in a locked box while its taking the measurements. I would check online for Oceanography equipment and look for an adapter to link your salinity measurements to your computer directly and then just sort out how many hours each set of readings were taken. A SAS program would excellent for the data as well. 6. I am going through the same sort of issue right now, although my primary concern is measuring water level (but I eventually will add salinity sensors and for logistical/cost reasons, I plan on sticking with one manufacturer). Below is an e-mail that was forwarded to me with links to several manufacturers that make loggers that can measure and record salinities. In addition to the companies listed in that e-mail, In-situ (www.in-situ.com) makes salinity loggers (~$2200 for their Aqua Troll 200). A company called Solinst (www.solinst.com) is developing a salinity logger but the instrument was still undergoing testing in their R&D department when I contacted them last week. Finally, Hydrolab (www.hydrolab.com) sells several sondes that can be outfitted with conductivity (salinity) sensors, as well as other sensors (pH, oxygen, etc). http://www.star-oddi.com/ <http://www.star-oddi.com/ http://www.odysseydatarecording.com/odyssey_productslist.php <http://www.odysseydatarecording.com/odyssey_productslist.php www.onsetcomp.com http://www.swstechnology.com/equipment_product.php?ID=1 <http://mail.univ-ovidius.ro/exchweb/bin/redir.asp?URL=http:// www.swstechnology.com/equipment_product.php?ID=1 https://www.ysi.com/portal/page/portal/YSI_Environmental/Products/ Product_Family/Product?productID=EMS_SON08_600XLM <http://mail.univ-ovidius.ro/exchweb/bin/redir.asp?URL=https:// www.ysi.com/portal/page/portal/YSI_Environmental/Products/ Product_Family/Product?productID=EMS_SON08_600XLM Dr. Russell Burke Department of Biology 114 Hofstra University Hempstead, NY 11549 voice: (516) 463-5521 fax: 516-463-5112 http://www.people.hofstra.edu/russell_l_burke/
