Little Lagoon Preservation Society

Little Lagoon Preservation SocietyAlabama Water WatchChemical and Bacterial Monitoring ProtocolsOverviewLLPS has been involved in a long-running study of water quality and microbial life in Little LagoonProtocols used by LLPS differ from those used by AWWThis study conducted to compare and contrast the results of LLPS and AWW methodologiesData suggests that results of both methods are comparableAWW bacteria monitoring caught a short lived e.coli bloom in the east end of the Lagoon in late Oct LLPS Water Quality Research

Research affiliated with DISL, USA, & othersData records to help characterize normal conditions and patternsCurrent efforts are primarily focused on physical parameters and presence of microbial life

Images retrieved from organization websites3LLPS ProtocolsChemical data obtained with YSI-556 probeSamples measured in a 5-gallon bucketTemperature, salinity, dissolved oxygen, pH, and barometric pressureE. coli samples from all five sites cultured with agar, one per site

Image retrieved from www.ysi.com4Alabama Water Watch

Statewide organization, community-orientedCooperative effort of citizen monitors, a non-profit association, and university researchersMajor focus is outreach and education, EPA-approved monitoring of state watersImage retrieved from www.alabamawaterwatch.org5AWW Protocols

Data obtained by titration, colorimetry, & refraction of lightSamples taken directly from source waterDO, salinity, pH; also alkalinity & hardnessE. coli samples cultured in triplicateEPA-accepted protocolsImage retrieved from www.lamotte.com6Whats the Difference?LLPS ProtocolsAWW ProtocolsCompatibility of records with previous research dataIf calibrated properly, probe data should be more precise than titration, eye-ballingQuicker, less prone to user error

Methodology proven and widely used for decadesCompatibility with other monitor groupsCheaper than a probeTriplication of bacteria samples more expensive but more accurateWhy Do Both?Provide verification of probe data, calibrationEstablish compatibility between methodologiesImprove accuracy with independent methodsEnhance reliability of both systems by finding correlation of data and estimate variations

Site 0 Dissolved OxygenSite 1 Dissolved OxygenSite 2 Dissolved OxygenDissolved Oxygen DataProbe readings were consistently higher than titration resultsMargin of error between results too largeDiscrepancies seem to be related to methodology: direct sampling typically has higher oxygen readings than in a bucketCorrelation Coefficient0.730Standard Error0.773Upper Prediction (for 7.00, 95%)7.217Lower Prediction (for 7.00, 95%)3.834Coefficient of Determination53.33%Coefficient of Non-determination46.67%Experimental DO DataExperimental DO DataProbe readings taken directly and then in a bucket on several tripsValues for DO much closer to AWW resultsReadings no longer consistently higherExperimental sample size only n=6, so correlation may be exaggeratedCorrelation Coefficient0.981Standard Error0.179Upper Prediction (for 7.00, 95%)7.442Lower Prediction (for 7.00, 95%)6.386Coefficient of Determination96.33%Coefficient of Non-determination3.67%DO ConclusionsDiscrepancies seem to be related to agitation of water and possibly temperature as wellNormal LLPS procedures (bucket sampling) yield DO results much closer to titration resultsDiscrepancies may be a deliberate artifact of study methodology: microbial life may not be mobile enough to benefit from higher oxygen availability of agitated or flowing waterLower readings may indicate what is available to bacteria, phytoplankton, etc., but not fish, crabs, etc.Site 0 pHSite 1 pHSite 2 pHpH DataProbe readings and AWW generally close, but vary both higher and lowerMargin of error between probe/AWW close to rounding error inherent to AWW protocolDiscrepancies likely related to user bias

Correlation Coefficient0.812Standard Error0.223Upper Prediction (for 7.50, 95%)7.935Lower Prediction (for 7.50, 95%)6.960Coefficient of Determination65.98%Coefficient of Non-determination34.02%pH ConclusionsNormal pH range of lagoon hard to measure with colorimetryRounding to nearest integer or half-integer suggests 0.25 errorProbe results not highly correlative, but error margins are comparable to AWW method

Image retrieved from www.amazon.com; edited for contrast and clarity.20Site 0 SalinitySite 1 SalinitySite 2 SalinitySalinity DataProbe readings and AWW results are very close to one anotherRefractometer inaccuracy expected to be up to +/- 1.00 to 2.00High correlation and small standard error suggest both methods are very accurate

Correlation Coefficient0.998Standard Error0.779Upper Prediction (for 25.00, 95%)26.073Lower Prediction (for 25.00, 95%)22.706Coefficient of Determination99.56%Coefficient of Non-determination0.44%Salinity Conclusions

Correlation and error suggest that probe data is at least as accurate as refractometer dataDiscrepancies probably from user rounding, not statistically significantSalinity data acceptance between databases should be soundImage retrieved from www.atj.net.au25Bacteria Sampling SitesSite 0Site 1

Images retrieved from maps.google.com26Bacteria SamplingLLPS bacteria records not acceptable by AWW standardsAWW needs triplicates for each site; greater degree of accuracy than single platesSite 1 and Site 0 now being sampled with AWW protocols

Image retrieved from www.oxoid.com27Site 0 Bacteria

Image retrieved from www.alabamawaterwatch.org28Site 0 BacteriaOften has E. coli levels within or exceeding the threshold for concernIn town; close proximity to a Gulf Shores Utilities sewer lift stationClose to a marsh area which supports large numbers of birds, possibly other animals

Site 1 Bacteria

Image retrieved from www.alabamawaterwatch.org

30Site 1 Bacteria

Normal E. coli levels are pretty low, with a few exceptionsSpike not associated with any rain, spills, or other known eventsLots of houses nearby, also many birds and occasional boatsBacteria CountsNormalized32Cautionary NotesThe E. coli spike at Site 1 is of unknown origin, but dissipated rapidly, probably poses little threatGSU reports no leaks; possibility of a leak on private property not monitored by GSU; sewer or septicCould be related to the presence of wildlife, especially large flocks of birdsCould be the result of an isolated dumping incident or boating spill in or near the canal streamCould be a natural disturbance of latent bacterial spores resident in the lagoon sedimentFuture ConsiderationsGSU is planning to install a new lift station nearby, but these plans are apparently unrelated to the isolated incident at Site 1There has been discussion to have LLPS provide GSU with our bacteria data to facilitate response to and public notice of potential bacterial threatsLLPS assisting AWW with new Enterococcus bacteria testing procedures, which are believed to be more accurate for brackish environmentsThank You!Thank you to all of the members of the Little Lagoon Preservation Society for your dedication and support. Without the help of community-minded people like you to protect and preserve our natural resources, the work of conservation groups, researchers, and citizen scientists would be much more challenging and probably less fruitful.