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Nutritional and contaminant stressors influence organismal physiology, trophic interactions, community structure, and ecosystem-level processes; however, the interactions between toxicity and elemental imbalance in food resources have been examined in only a few ecotoxicity studies. Integrating well-developed ecological theories that cross all levels of biological organization can enhance our understanding of ecotoxicology. In the present article, we underline the opportunity to couple concepts and approaches used in the theory of ecological stoichiometry (ES) to ask ecotoxicological questions and introduce stoichiometric ecotoxicology, a subfield in ecology that examines how contaminant stress, nutrient supply, and elemental constraints interact throughout all levels of biological organization. This conceptual framework unifying ecotoxicology with ES offers potential for both empirical and theoretical studies to deepen our mechanistic understanding of the adverse outcomes of chemicals across ecological scales and improve the predictive powers of ecotoxicology.

In large lakes, metal availability sometimes limits the acquisition of nutrients (nitrogen, N and phosphorus, P) in offshore waters that are relatively isolated from tributaries and sediments. We hypothesize that metals may also be important within harmful algal blooms (HABs). HABs occur where nutrient loads are elevated, but bioassays often indicate that phytoplankton in HABs are N or P limited. Nutrient limitation may be exacerbated by corresponding limitations in several metals (i.e. nickel - Ni, molybdenum - Mo, zinc - Zn, and iron - Fe) that facilitate uptake and transformation of oxidized and organic forms of nutrients, such as urea, nitrate and organic phosphorus. The cyanotoxin microcystin has been hypothesized to have a role in metal management, so metal demand may also influence the toxicity of HABs. Here, we used nutrient diffusing substrates to measure how N, P, Ni, Mo, Zn and Fe amendments influenced the growth and toxicity of periphyton. Periphyton was grown suspended in 10 nearshore sites in Lake Michigan and Lake Erie (5 with and 5 without perennial HABs). Outside of blooms, we found no evidence for metal limitation or co-limitation. However, evidence for metal co-limitation was observed in two HABs sites (Zn in Green Bay and Zn, Mo, Ni and Fe in Sandusky Bay). N, P and Zn amendments all stimulated microcystin content in Maumee Bay. These data indicate that nutrient limitation occurs even within blooms, and the availability of metals may have an influence on growth, community composition and toxicity. [ABSTRACT FROM AUTHOR]

Efforts to reduce the frequency, extent, and toxicity of harmful algal blooms (HABs) require knowledge about drivers of algal growth, toxin production, and shifts in phytoplankton community composition to cyanobacterial dominance. Although labile nitrogen (N) and phosphorus (P) fuel primary production, micronutrients also play roles as the enzymatic engines that facilitate rapid and efficient growth and toxin production. Macro‐ and micronutrient availability can shape community composition and function by selecting for particular taxa. To address how phytoplankton in two Great Lakes subbasins respond to macro‐ and micronutrients, we conducted bottle incubation enrichment experiments using water collected from two blooming and two nonblooming sites in Lakes Erie and Michigan during late summer (August). Three of the four sites exhibited multi‐nutrient limitation of growth. Both blooming sites responded strongest to NH4+ enrichment. Both nonblooming sites responded the strongest to PO43− enrichment, and three of the four sites responded in some way to a mix of micronutrients (Fe, Mn, Mo, Ni, and Zn). Microcystis aeruginosa relative abundance increased most with N enrichment, while P enrichment increased the abundance of diatoms and chlorophytes. At the Fox River, N‐enriched communities grew 10%–20% more than non‐N enriched communities (measured as chlorophyll a), and N‐enriched communities had, on average, over twice as much microcystin (non‐N communities average MC = 2.45 μg · L−1, +N communities MC = 5.35 μg · L−1). These overarching trends support the idea that control of HABs may not be effective with a P‐only approach. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine how my reading instruction had been situated within my school's literacy program. As a way to investigate this study, I employed qualitative teacher research. I used reading theory (Whole Language and Direct Instruction) as the analytical lens for my analysis. The results illustrated how the Direct Instruction aspects of the literacy program permeated into my classroom, altered my teaching practices, and impacted student learning. While there were both positives and negatives to the instructional techniques, teacher and student choice was limited. (Contains 2 footnotes.)

This article reports on a study investigating how elementary teachers experienced the literacy initiatives that have been implemented in schools across PEI over the past five years. Such initiatives included the implementation of standardized instructional and assessment materials across the board and the emphasis on consistency of program use, reporting, and evaluation. Data were gathered through an online survey and interviews. Throughout this study, issues of professionalism, emotional impact, and teacher resistance were explored. This article focuses specifically on the issue of teacher professionalism and its relationship with prescribed curriculum. Findings suggest that professionalism is challenged when teachers attempt to adhere to the fidelity of program processes. However, fidelity to the purpose of a program would allow for teacher decision-making and autonomy within the context of any given program or practice.

The article discusses the importance of understanding math problems in the classroom. It emphasizes the need for students to fully comprehend the problem before attempting to solve it. The author suggests several strategies to support students in understanding the problem, including questioning, paraphrasing, finding the match, and think-aloud. These strategies can help students navigate the problem-solving process and make informed decisions. The article highlights the significance of taking the time to understand the problem and provides practical techniques to enhance students' understanding. [Extracted from the article]

The open waters of large lakes can sometimes become so depleted in important metals that phytoplankton communities become either growth limited or limited in some metabolic function. Metals such as Fe, Ni, Mo, and Zn are used as co-factors for enzymes by phytoplankton in core metabolic functions, as well as metabolic pathways that allow phytoplankton to use less preferred forms of N and P (e.g. nitrates, urea, and organic phosphorus). In the Laurentian Great Lakes, metal limitation has been observed primarily in waters that are isolated from tributary inputs and sediment exchange. These are situations where the supply of metals is very low relative to demand. We hypothesized that another situation where metal limitation could occur is within algal blooms, where the demand for metals is high because preferred forms of N and P are often low or absent and the phytoplankton biomass is extremely high. As a preliminary test of this hypothesis, we performed seven laboratory incubation experiments on naturally occurring phytoplankton communities from two nearshore habitats that frequently experience blooms (Green Bay in Lake Michigan and Maumee Bay in Lake Erie). Metals and labile nutrients (inorganic N and P) were often present at low concentrations or below the method detection limit. Amendments of inorganic N (5 experiments) and P (1 one experiment) resulted in increased chlorophyll in laboratory incubations, but metal amendments alone never appeared to stimulate growth. Although we attempted to sample during conditions when we hypothesized metal limitation would be most likely, we cannot rule out the possibility that metal limitation is occurring at other times in these eutrophic nearshore areas. Further, metal availability could affect other aspects of the phytoplankton community, such as the production of cyanotoxins or the interactions between different phytoplankton taxa. Although harmful algal blooms are more likely to develop when external nutrient loads are high, while a bloom is occurring, the concentrations of key nutrients (nitrogen and phosphorus) can be very low. When key nutrients are in low abundance or absent, algae require additional metals to take advantage of poorer quality versions of these key nutrients. We hypothesized that metals might become growth-limiting in blooms, which might in turn have implications for predicting bloom toxicity. Seven experiments on phytoplankton from nearshore Great Lakes areas experiencing algal blooms did not show evidence for growth-limitation of algae, although the spatial and temporal extent of these experiments is limited. [ABSTRACT FROM AUTHOR]

When I was asked to teach the entire literacy curriculum to my grade six students in only five months, I implemented reading conferences as an instructional practice to deepen students' reading comprehension. Classroom events related to reading conferences, student decision-making, and instructional planning were recorded in a journal. This study reflected a shift from traditional teaching to a student-centered approach wherein student learning was used to guide instruction. Findings demonstrated how instructional practices were changed to reflect student learning and how the use of reading conferences promoted dialogue between teacher and student.

This article shares the experience of a teacher investigating the tension between a mandated literacy program and his desire to teach in response to his perceptions of students' needs. Qualitative teacher research methodology is used to study the impact of mandated literacy practices on teaching and learning; and to answer the question: how is my teaching situated within the literacy program? Data, collected through a research journal, were analyzed using a Foucauldian lens of discourse, and reading theory. This study unveils the mechanisms supporting mandates, and conflicts between theoretical and practical applications of mandated practices and the teacher's instructional beliefs. (Contains 1 footnote.)