A model for the prediction of total phosphorus was developed and tested using data on 704 nautral artificial lakes including 626 in U.S. Environmental Protection Agency (EPA) National Eutrophication Survey. statistical analysis showed that best estimate sedimentation coefficient (σ) Vollenweider equation was[Formula: see text]for where L is areal loading rate (mg∙m −2 ∙yr −1 ) z mean depth (m). The yields unbiased estimates concentrations over a wide range lake types has 95% confidence...

ABSTRACT: Models for the prediction of chlorophyll a concentrations were developed and tested using data on 223 Florida lakes. A statistical analysis showed that best model was log (Chl ) =−2.49 + 0.269 (TP) 1.06 (TN) or (TN/TP) 1.33 where Chl is concentration (mg m ‐3 ), TP total phosphorus TN nitrogen ). The yields unbiased estimates over wide range lake types has 95 percent confidence interval 29–319 calculated concentrations. Other models, especially published Dillon‐Rigler...

Rapid climate changes may potentially have strong impacts on the ecosystem structure and nutrient dynamics of lakes as well implications for water quality. We used a space-for-time approach to elucidate such possible effects by comparing data from 1656 shallow (mean depth <3 m) in north temperate Denmark (DK) subtropical Florida (FL). The were categorized into 7 total phosphorus (TP) classes within range 2 300 µg L−1. Physicochemical variables showed significant seasonal differences, which...

ABSTRACT Because the use of volunteer samplers is a very cost-effective way to collect large amounts information on lakes over space and time, we studied reliability protocols used by Florida LAKEWATCH program. We found that chlorophyll extractions with hot ethanol gave values were no different from those obtained standard method grinding acetone. In comparative study 125 data collected volunteers comparable professionals. Mean Secchi disk depth, TP, TN, citizens strongly correlated (r >...

Nutrient-chlorophyll (CHL) relationships were developed using a large data set collected in Florida over the last 10 years consisting of monthly total phosphorus (TP), nitrogen (TN), and CHL concentrations from 360 lakes. The precision these five additional published was examined. 95% confidence interval for best available TP-CHL model is 30-325% calculated value. Analysis associated nutrient indicate that relationship sigmoid, although linear response found TP range 3-160 µg·L -1 . maximum...

ABSTRACT We applied wave theory to calculate the extent and frequency that we would expect wave-driven surface water movements disturb sediments in 36 Florida lakes covering a broad range of areas mean depths. The calculated per cent lakebed subject disturbance at one time or another ranged from 6 100% 50% was disturbed 0 65%. large lakes, Apopka, Okeechobee, Istokpoga showed high levels disturbance, which consistent with conclusions previous investigations. Historic level fluctuations Lake...

ABSTRACT Average annual total phosphorus concentrations in Lake Okeechobee increased from 0.049 mg/L 1973 to 0.098 1984. The increases were not correlated external inputs, but changes lake water levels. It is proposed that the flooding of marshes and exposed bottom primarily caused concentrations, resuspension sediments by wind action may also be a major factor influencing in-lake concentrations. Reducing inputs 40 percent as Technical Advisory Committee (LOTAC) will significantly improve...

Phytoplankton samples collected from 165 Florida lakes were examined to determine relationships between blue-green algal abundance and environmental conditions. Blue-green biomass in the was weakly correlated (r = −0.34) with water transparency concentration of total nitrogen (TN) 0.47) phosphorus (TP) 0.33). The relative contribution algae phytoplankton biomass, however, did not decrease TN/TP &gt; 29. strongly 0.90) became consistently dominant when exceeded 100 mg/L.

Florida Department of Environmental Protection (FDEP) professional biologists and LAKEWATCH volunteers sampled 27 lakes simultaneously to measure the concentrations total phosphorus, nitrogen, chlorophyll. Each program used their Standard Operating Procedures for both field laboratory activities determine data comparability. Results showed that were nearly equivalent FDEP's, which collected using stringent quality assurance (QA) protocols analyzed in a National Laboratory Accreditation...

Individual Secchi disk measurements (975,760) were gathered from across the United States to understand regional distribution in water transparency. Compiled represented 14,421 US waterbodies. Average transparency ranged <0.1 31.6 m with transparencies <1.1 25% of sampled waterbodies, <2.0 50% and <3.3 75% Of population examined 10% had mean exceeding 4.8 m. states lowest (<0.7 m) Delaware, Louisiana, Mississippi, Nebraska, Oklahoma, South Dakota, while greatest (>3.5 Alaska, Maine, Montana,...

An infestation of hydrilla Hydrilla verticillata caused an 85% reduction in angler effort at Orange Lake, Florida, 1977 when plant coverage exceeded 80% the lake. Nonlocal anglers were only 3% total number fishing lake 1977, but 37% during 1978 and 1979, was less than 19%. Although use Lake greatly reduced peak infestation, fish caught per hour equivalent to or greater that all other study years for species sport fish. The almost complete did not lower population harvestable largemouth bass...

ABSTRACT A limnological survey of 165 Florida lakes was conducted between September 1979 and August 1980 to determine their chemical trophic state characteristics. wide range conditions documented. Average lake pH values ranged from 4.1 9.2 average total alkalinity concentrations 0 204 mg/L as calcium carbonate (CaCO3). specific conductance 11 over 5600 μS/cm at 25° C. Mean nitrogen 0.063 4.6 mean phosphorus 3 834 mg/m3. Although states oligotrophic hypereutrophic, a group can be...

Using data collected with 3 different methods, we found no decreases in the average water clarity of Maine (USA) lakes over periods time. Field measurements Secchi disk depths summer months by volunteer samplers several hundred showed a small, statistically significant increase transparency during period 1976 through 2013. A reanalysis satellite-inferred between 1990 and 2010 trend In addition, diatom-inferred from short sediment cores randomly selected group analyzed US Environmental...

Canfield DE Jr, Bachmann RW, Hoyer MV. 2020. Restoration of Lake Okeechobee, Florida: mission impossible? Reserv Manage. XX:XXX–XXX. Legally mandated eutrophication restoration goals for Okeechobee (FL) are unachievable, therefore assigning managers a "mission impossible." Since the 1970s, efforts have focused on reducing pelagic total phosphorus (TP) to ∼40 µg/L. A daily maximum load (TMDL) 140 metric tons (t)/yr was adopted by Florida Department Environmental Protection in 1999 (effective...

ABSTRACT Data collected during a limnological survey of 165 Florida lakes were used to examine statistical relations between chlorophyll concentrations and the abundance total zooplankton, cladocerans, copepods, crustaceans, rotifers. Abundances different groupings zooplankton positively correlated with concentrations, but all correlation coefficients less than 0.72. Rotifers most strongly summer (r=0.71). No major changes in community composition could be demonstrated increasing levels....

Abstract A survey of microcystin in 187 Florida lakes was completed from Jan to Dec 2006. Annual average concentrations the ranged nondetectable (< 0.1 μ g/L) 12 g/L, with individual water samples (N = 862) ranging 32 g/L. Only 7% all exceeded World Health Organization (WHO) drinking guidance value 1 Three collected two (0.3%) WHO recreational 20 Using chlorophyll and Secchi depth measurements, tables were constructed predict probability that values lakes. Additionally, six hypereutrophic...

Abstract Using data from 1387 lakes collected over 3 decades, we found a wide range in the concentrations of total phosphorus (TP), nitrogen (TN) and chlorophyll (Chl-a) Florida lakes, that edaphic factors as outlined by United States Environmental Protection Agency's Lake Regions were dominant determining plant nutrients state's lakes. The hypothesis majority eutrophic without known point source pollution are result nonpoint nutrient was tested several ways rejected. There no correlation...