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In New York State (NYS), Earth science teachers use the National Science Education Standards (NSES), the NYS Learning Standards for Mathematics, Science and Technology (NYS Standards), and the Physical Setting/Earth Science Core Curriculum (Core Curriculum) to create local curricula and daily lessons. In this study, a purposeful sample of experienced and innovative teachers provided insight on how NYS Earth science teachers organize their scope and sequences, align their lessons with the State standards-based documents, establish internal lesson coherence, and prepare their students for the state assessment, the Physical Setting/Earth Science Regents Examination (Regents Exam). Teachers provided responses to a questionnaire regarding their scope and sequence and typical lessons they teach for each unit. These data were then reviewed by the first author as well as by a team of Earth science education experts. Teachers' scope and sequences were well aligned with the Core Curriculum and Regents, but misalignment was found between their lessons and the Core Curriculum as well as between the stated objectives for their students and evaluation of those objectives. The insights gained from this analysis of the NYS system could be helpful to other states as they move toward increased standards-based Earth science curricula. Among other suggestions, it is recommended that the Core Curriculum be revised to emphasize alignment principles and more opportunity be provided for teacher professional development focused on alignment issues relative to the state standards and enhanced internal lesson coherence. [ABSTRACT FROM AUTHOR]

Biofilms collected on Plexiglass substrates, from a freshwater pond in northern New York State, were examined microscopically for naked amoebae densities, sizes, diversity, and estimated C-biomass. Five samples were obtained during summer 2006 and 2007. The densities ranged from 109 to 136/cm2 biofilm surface and 285 to 550/mg biofilm dry weight. Sizes ranged from 13 to 200 μm. Diversities ranged from 4.23 to 4.55. C-biomass ranged from 64 to 543 ng C/cm2 and 125 to 1,700 μg C/g dry weight. Thirty morphospecies were identified among the five samples, including very large amoebae in the range of 100-200 μm. Large amoebae (≥ 50 μm) accounted for the largest proportion of the C-biomass. [ABSTRACT FROM AUTHOR]

Abstract: We report on the emergence of Cochlodinium polykrikoides blooms in the Peconic Estuary and Shinnecock Bay, NY, USA, during 2002–2006. Blooms occurred during late summer when temperatures and salinities ranged from 20 to 25°C and 22 to 30ppt, respectively. Bloom patches achieved cell densities exceeding 105 ml−1 and chlorophyll a levels exceeding 100μgl−1, while background bloom densities were typically 103–104 cellsml−1. Light, scanning electron and ultrathin-section transmission electron microscopy suggested that cells isolated from blooms displayed characteristics of C. polykrikoides and provide the first clear documentation of the fine structure for this species. Sequencing of a hypervariable region of the large subunit rDNA confirmed this finding, displaying 100% similarity to other North American C. polykrikoides strains, but a lower similarity to strains from Southeast Asia (88–90%). Bioassay experiments demonstrated that 24h exposure to bloom waters (>5×104 cellsml−1) killed 100% of multiple fish species (1-week-old Cyprinodon variegates, adult Fundulus majalis, adult Menidia menidia) and 80% of adult Fundulus heteroclitus. Microscopic evaluation of the gills of moribund fish revealed epithelial proliferation with focal areas of fusion of gill lamellae, suggesting impairment of gill function (e.g. respiration, nitrogen excretion, ion balance). Lower fish mortality was observed at intermediate C. polykrikoides densities (103–104 cellsml−1), while fish survived for 48h at cell densities below 1×103 cellsml−1. The inability of frozen and thawed-, or filtered (0.2μm)-bloom water to cause fish mortality suggested that the thick polysaccharide layer associated with cell membranes and/or a toxin principle within this layer may be responsible for fish mortality. Juvenile bay scallops (Argopecten irradians) and American oysters (Crassostrea virginica) experienced elevated mortality compared to control treatments during a 9-day exposure to bloom water (∼5×104 cellsml−1). Surviving scallops exposed to bloom water also experienced significantly reduced growth rates. Moribund shellfish displayed hyperplasia, hemorrhaging, squamation, and apoptosis in gill and digestive tissues with gill inflammation specifically associated with areas containing C. polykrikoides cells. In summary, our results indicate C. polykrikoides blooms have become annual events on eastern Long Island and that bloom waters are capable of causing rapid mortality in multiple species of finfish and shellfish. [Copyright &y& Elsevier]

We investigated the impact of viruses, nutrient loading, and microzooplankon grazing on phytoplankton communities in two New York estuaries that hosted blooms of the brown tide alga Aureococcus anophagefferens during 2000 and 2002. The absence of a bloom at one location during 2002 allowed for the fortuitous comparison of a bloom and non-bloom year at the same location as well as a comparison of two sites experiencing bloom and non-bloom conditions during the same year. During the study, blooms were found at locations with high levels of dissolved organic nitrogen and lower nitrate concentrations compared to a non-bloom location. Experimental additions of inorganic nitrogen and phosphorus yielded growth rates within the total phytoplankton community which significantly exceeded control treatments in 83% of experiments, while A. anophagefferens experienced significantly increased growth during only 20% of experimental inorganic nutrient additions. Consistent with prior research, these results suggest brown tides are not caused by eutrophication, but instead are more likely to occur when sources of labile DOM are readily available. Microzooplankton grazing rates on the total phytoplankton community during a bloom were lower than grazing rates at a non-bloom site, and grazing rates on A. anophagefferens were lower than grazing rates on the total community on some dates, suggesting that reduced grazing mortality may also promote brown tides. Mean densities of viruses during blooms (3 × 108 ml-1) were elevated compared to most estuarine environments and were twice the levels found at a non-bloom site. Experimental enrichment of the natural viral densities yielded a significant increase in A. anophagefferens growth rates relative to control treatments when background levels of viruses were low (<1.7 × 108 ml-1), suggesting that viruses may promote bloom occurrence by regenerating DOM or altering the composition of microbial communities. [Copyright &y& Elsevier]