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Species' response to rapid climate change can be measured through shifts in timing of recurring biological events, known as phenology. The Gulf of Maine is one of the most rapidly warming regions of the ocean, and thus an ideal system to study phenological and biological responses to climate change. A better understanding of climate-induced changes in phenology is needed to effectively and adaptively manage human-wildlife conflicts. Using data from a 20+ year marine mammal observation program, we tested the hypothesis that the phenology of large whale habitat use in Cape Cod Bay has changed and is related to regional-scale shifts in the thermal onset of spring. We used a multi-season occupancy model to measure phenological shifts and evaluate trends in the date of peak habitat use for North Atlantic right (Eubalaena glacialis), humpback (Megaptera novaeangliae), and fin (Balaenoptera physalus) whales. The date of peak habitat use shifted by +18.1 days (0.90 days/year) for right whales and +19.1 days (0.96 days/year) for humpback whales. We then evaluated interannual variability in peak habitat use relative to thermal spring transition dates (STD), and hypothesized that right whales, as planktivorous specialist feeders, would exhibit a stronger response to thermal phenology than fin and humpback whales, which are more generalist piscivorous feeders. There was a significant negative effect of western region STD on right whale habitat use, and a significant positive effect of eastern region STD on fin whale habitat use indicating differential responses to spatial seasonal conditions. Protections for threatened and endangered whales have been designed to align with expected phenology of habitat use. Our results show that whales are becoming mismatched with static seasonal management measures through shifts in their timing of habitat use, and they suggest that effective management strategies may need to alter protections as species adapt to climate change.

Quantifying student engagement with online learning resources on virtual learning environments such as BlackBoard is important in understanding how these technologies enhance the student learning. In the present study, it was examined when, and how often, first-year students accessed lecture recordings, lecture slides, and lecture notes via BlackBoard, in an introductory natural resource course taken by both on campus students and remote students. The findings demonstrated that lecture recordings were not well utilized by students--although only 58% of on campus students attended face-to-face lectures, less than 15% of absent students downloaded the missed lecture. Overall, more students downloaded lecture slides (an average of 63% per week) than notes (38%) or recordings (16%). Indeed, the average student downloaded only 1.1 types of the 3 online resources (recordings, slides, and notes) that were available each week, with 5.7% of students downloading all 3 types of resources, 23% downloading 2 types of resources, 42% downloading only 1 type of resource, and 29% downloading none of the 3 types of resources. Finally, remote students were more likely to download lecture notes and recordings than were on campus students. The information presented here is important in understanding student behaviour and engagement.

Soil provides multiple, diverse functions, with these underpinning both planetary and human health. For planetary health, soil contributes to multiple critical processes, including through biomass production, by regulating the carbon pool, providing a habitat for 25% of global biodiversity, cycling the nutrients upon which terrestrial systems depend, and cycling water. Soil also underpins human health; humans use soil to provide 98.8% of our food and sustain our nutrition, regulate pathogens, and supply medicines. However, humans have tended to focus on soil almost solely for producing biomass (food, fiber, and energy) through intensive agriculture, and this narrow focus now causes rapid soil degradation, including through loss of soil organic matter, erosion, and salinization. This degradation directly harms planetary health and reduces the ability of soil to support health of future human generations. We argue that a healthy soil is a soil that is multifunctional and is capable of underpinning human and planetary health. Using this definition, a broad conceptual framework is provided for quantifying soil health, with such an approach enabling a shift in the way that we think about, plan, and manage systems to ensure ongoing planetary and human health. [ABSTRACT FROM AUTHOR]

The population of the critically endangered North Atlantic right whale, Eubalaena glacialis, numbers approximately 336 individuals, and continues to decline. Current development and implementation of protection measures and monitoring of right whale presence relies on visual surveys from vessel and aerial platforms, and passive acoustic monitoring, which contribute to location data. Here we demonstrate that satellite imagery can be used to detect and confirm the North Atlantic right whales at a species level using newly available imaging methods, providing another tool to inform conservation efforts. Using optical satellite imagery with 15 cm resolution, 25 right whales were observed in Cape Cod Bay on April 24, 2021. Species confirmation was possible due to clearly visible callosity patterns indicative of their species within this range. Although the variations in callosity patterns commonly used to identify individuals were too small to be resolved at this image resolution, one whale with large distinctive markings visible on his body was identified at an individual level from satellite imagery alone. Although visual and acoustic survey methods can be combined for monitoring this species in critical habitats, satellite‐based monitoring can be especially helpful to understand whale presence outside the areas monitored with existing visual and acoustic detection methods. [ABSTRACT FROM AUTHOR]

Aluminium (Al) K‐ and L‐edge X‐ray absorption near‐edge structure (XANES) has been used to examine Al speciation in minerals but it remains unclear whether it is suitable for in situ analyses of Al speciation within plants. The XANES analyses for nine standard compounds and root tissues from soybean (Glycine max), buckwheat (Fagopyrum tataricum), and Arabidopsis (Arabidopsis thaliana) were conducted in situ. It was found that K‐edge XANES is suitable for differentiating between tetrahedral coordination (peak of 1566 eV) and octahedral coordination (peak of 1568 to 1571 eV) Al, but not suitable for separating Al binding to some of the common physiologically relevant compounds in plant tissues. The Al L‐edge XANES, which is more sensitive to changes in the chemical environment, was then examined. However, the poorer detection limit for analyses prevented differentiation of the Al forms in the plant tissues because of their comparatively low Al concentration. Where forms of Al differ markedly, K‐edge analyses are likely to be of value for the examination of Al speciation in plant tissues. However, the apparent inability of Al K‐edge XANES to differentiate between some of the physiologically relevant forms of Al may potentially limit its application within plant tissues, as does the poorer sensitivity at the L‐edge. [ABSTRACT FROM AUTHOR]

Summary: Soil acidity and waterlogging increase manganese (Mn) in leaf tissues to potentially toxic concentrations, an effect reportedly alleviated by increased silicon (Si) and phosphorus (P) supply. Effects of Si and P on Mn toxicity were studied in four plant species using synchrotron‐based micro X‐ray fluorescence (μ‐XRF) and nanoscale secondary ion mass spectrometry (NanoSIMS) to determine Mn distribution in leaf tissues and using synchrotron‐based X‐ray absorption spectroscopy (XAS) to measure Mn speciation in leaves, stems and roots. A concentration of 30 μM Mn in solution was toxic to cowpea and soybean, with 400 μM Mn toxic to sunflower but not white lupin. Unexpectedly, μ‐XRF analysis revealed that 1.4 mM Si in solution decreased Mn toxicity symptoms through increased Mn localization in leaf tissues. NanoSIMS showed Mn and Si co‐localized in the apoplast of soybean epidermal cells and basal cells of sunflower trichomes. Concomitantly, added Si decreased oxidation of Mn(II) to Mn(III) and Mn(IV). An increase from 5 to 50 μM P in solution changed some Mn toxicity symptoms but had little effect on Mn distribution or speciation. We conclude that Si increases localized apoplastic sorption of Mn in cowpea, soybean and sunflower leaves thereby decreasing free Mn2+ accumulation in the apoplast or cytoplasm. [ABSTRACT FROM AUTHOR]

Knowledge of the distribution of selenium (Se) species within plant tissues will assist in understanding the mechanisms of Se uptake and translocation, but in situ analysis of fresh and highly hydrated plant tissues is challenging. Using synchrotron-based fluorescence X-ray absorption near-edge spectroscopy (XANES) imaging to provide laterally resolved data, the speciation of Se in fresh roots and leaves of wheat (Triticum aestivum L.) and rice (Oryza sativa L.) supplied with 1 nM of either selenate or selenite was investigated. For plant roots exposed to selenate, the majority of the Se was efficiently converted to C-Se-C compounds (i.e. methylselenocysteine or selenomethionine) as selenate was transported radially through the root cylinder. Indeed, even in the rhizodermis which is exposed directly to the bulk solution, only 12-31% of the Se was present as uncomplexed selenate. The C-Se-C compounds were probably sequestered within the roots, whilst much of the remaining uncomplexed Se was translocated to the leaves--selenate accounting for 52-56% of the total Se in the leaves. In a similar manner, for plants exposed to selenite, the Se was efficiently converted to C-Se-C compounds within the roots, with only a small proportion of uncomplexed selenite observed within the outer root tissues. This resulted in a substantial decrease in translocation of Se from the roots to leaves of selenite-exposed plants. This study provides important information for understanding the mechanisms responsible for the uptake and subsequent transformation of Se in plants. [ABSTRACT FROM AUTHOR]

The concentration, chemical speciation, and spatial distribution of essential and toxic mineral elements in cereal seeds have important implications for human health. To identify genes responsible for element uptake, translocation, and storage, high-throughput phenotyping methods are needed to visualize element distribution and concentration in seeds. Here, we used X-ray fluorescence microscopy (μ-XRF) as a method for rapid and high-throughput phenotyping of seed libraries and developed an ImageJ-based pipeline to analyze the spatial distribution of elements. Using this method, we nondestructively scanned 4,190 ethyl methanesulfonate (EMS)-mutagenized M1 rice (Oryza sativa) seeds and 533 diverse rice accessions in a genome-wide association study (GWAS) panel to simultaneously measure concentrations and spatial distribution of elements in the embryo, endosperm, and aleurone layer. A total of 692 putative mutants and 65 loci associated with the spatial distribution of elements in rice seed were identified. This powerful method provides a basis for investigating the genetics and molecular mechanisms controlling the accumulation and spatial variations of mineral elements in plant seeds., Competing Interests: Conflict of interest statement. None declared., (© American Society of Plant Biologists 2022. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)