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The western basin of Lake Erie has a history of recurrent cyanobacterial harmful algal blooms (HABs) despite decades of efforts by the United States and Canada to limit phosphorus loading, a major driver of the blooms. In response, the National Oceanic and Atmospheric Administration (NOAA) Great Lakes Environmental Research Laboratory (GLERL) and the Cooperative Institute for Great Lakes Research (CIGLR) created an annual sampling program to detect, monitor, assess, and predict HABs in western Lake Erie (WLE). Here we describe the data collected from this monitoring program from 2012 to 2021. This dataset includes observations on physicochemical properties, major nutrient fractions, phytoplankton pigments, microcystins, and optical properties for western Lake Erie. This dataset is particularly relevant for creating models, verifying and calibrating remote sensing algorithms, and informing experimental research to further understand the water quality dynamics that influence HABs in this internationally significant body of freshwater. The dataset can be freely accessed from NOAA National Centers for Environmental Information (NCEI) at 10.25921/11da-3x54 (Cooperative Institute for Great Lakes Research, University of Michigan and NOAA Great Lakes Environmental Research Laboratory, 2019). [ABSTRACT FROM AUTHOR]

Abstract: During the summer of 2006, the western basin of Lake Erie experienced a bloom of the toxigenic cyanobacterium Microcystis aeruginosa. Across 11 sites, intracellular, particulate-bound microcystin levels in the [...]

In bioavailability studies, the biota sediment accumulation factor (BSAF) is invoked to describe the thermodynamic partitioning of a hydrophobic organic contaminant (HOC) between the organism lipid and the organic carbon fraction of the sedimentary matrix and accounts for differences in bioavailability among sediments. Bioaccumulation experiments were performed with Lumbriculus variegatus and Diporeia species exposed in seven sediments dosed with 2,4,5,2′,4′,5′-hexachlorobiphenyl (HCBP) and benzo[a]pyrene (BaP) or pyrene (PY) and 3,4,3′,4′-tetrachlorobiphenyl (TCBP). The BSAF values for the nonplanar HCBP were consistent with equilibrium partitioning theory (EQP) and averaged 2.87 for L. variegatus and 1.45 for Diporeia, while the BSAF values for the planar compounds (BaP, PY, TCBP) were generally lower than estimated from EQP (<1). Correcting the BSAF values of the planar compounds for enhanced sorption due to black carbon improved the BSAF values for L. variegatus, generally resulting in values consistent with EQP, but substantial variation remained for Diporeia. The BSAF values for the planar compounds showed significant positive correlations with plant-derived carbon in sediments (lignin and pigments) but were more consistent for L. variegatus than for Diporeia. These correlations imply that compounds sorbed to plant-derived carbon are more bioavailable since this material is more likely ingested providing a second exposure route. [ABSTRACT FROM AUTHOR]

The amphipod, Diporeia spp., the dominant benthic macroinvertebrate in the Great Lakes offshore waters, has exhibited a substantial decline in recent years. This decline occurred after the invasion and colonization of the lakes by the zebra mussel, Dreissena polymorpha. It has been hypothesized that the decline is a direct result of the competition by the zebra mussel decreasing the amount of food available. This study examined the potential of other stressors, e.g., the presence of toxic materials, as the contributing or main cause of the decline. Bioassays were performed with sediments from stations currently devoid of Diporeia (St. Joseph, MI) and with those still having Diporeia populations. In 28-d mortality bioassays, no mortality was observed with any of the sediments tested. However, in avoidance/preference tests, sediments from St. Joseph, that are now devoid of Diporeia, were avoided compared to sediments from Saugatuck, Grand Haven, and Muskegon, which still have a population. This avoidance was not changed by the addition of either Spirulina Plus or Tetramin flakes to the sediment as a food source but was reversed by a fresh layer of the diatom, Fragillaria crotonensis, on the sediment. These studies suggest that despite the high carbon content of the St. Joseph sediment, the nutritional content of the sediment was limited. [ABSTRACT FROM AUTHOR]

Organic carbon is considered the major variable affecting the bioavailability of non-polar, sediment-associated contaminants. Previously,variation in bioavailability for some Great Lakes sediments comparedto a soil material was nearly a factor of 10 after carbon normalization. Because a soil might not truly represent sedimentary materials sediments and soils were gathered from several locations in the UnitedStates, Canada, and Finland. The accumulation kinetics of the amphipod Diporeia spp. were measured for pyrene, benzo[a]pyrene (BaP), 2,4,2',4'-tetrachlorobiphenyl (TCBP), and 2,4,5,2',4',5'-hexachlorobiphenyl (HCBP) sorbed to sediments and soils. The organic carbon content of the sediments ranged from 0.45--21.2% and 32.2--45.0% for soils. The bioavailability, measured as the uptake clearance (amount of sourcecompartment cleared of contaminant per mass of organism per hour), was controlled by the amount of organic carbon, particularly for the chlorinated biphenyls. However, for polycyclic aromatic hydrocarbons (PAH), bioavailability was controlled more by the organic carbon polarity represented by the carbon/nitrogen ratio of the sediment. PAH bioavailability increased as the ratio increased; thus, the more nonpolar the organic matter, the more available the compound. This polarity did not account for any of the chlorinated biphenyl bioavailability. The amount and type of mineral matrix of the sediment did not influence the bioavailability for either compound class. In addition, the amount of oxygen in the sediment was correlated with the bioavailability for BaP after carbon normalization. [ABSTRACT FROM AUTHOR]

Despite the initial success of extensive efforts to reduce phosphorus (P) loading to Lake Erie as a part of the Great Lakes Water Quality Agreement, Lake Erie appears to be undergoing a re-eutrophication and it is plagued by harmful algal blooms. To offer insights into potential lake responses under differing Maumee River loads and reveal recent changes with time, we explored patterns in phosphorus and chlorophyll a data from 2008 to 2018 collected in western Lake Erie near the mouth of the Maumee River. We found high, but relatively stable Maumee River and lake concentrations of total P (TP) and soluble reactive P (SRP) with no discernable annual or seasonal patterns. Maumee spring TP load was not strongly related to lake TP, and lake SRP concentrations were positively but weakly related to SRP loads. Lake TP was a strong predictor of chlorophyll a , but the relationship was weaker at sites closer to the Maumee. These results highlight spatial differences both in P concentration and the relationship between TP and chlorophyll a , and these indicate that spring phosphorus loads are a weak algal biomass predictor in the portion of the western basin of Lake Erie represented by these sampling stations.