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Background and aims Biological nitrogen fixation (BNF) supplies much of soybean ( Glycine max (L.) Merr.) nitrogen (N) demand, but reported fixation rates vary widely, leading to uncertainty in the soybean N cycle. We quantified whole-plant soybean BNF and N allocation using long-term 15 N labeling to assess whether BNF can offset grain N removal in a high-yielding system, and to quantify root contributions to fixed N. Methods...
Crystal defects drive gold remobilisation in arsenopyriteNARA Subscribed
Scaling the Spatial and Temporal Effects of Wrack Disturbance Across a Saltmarsh LandscapeNARA Subscribed
Disturbance effects are rarely distributed uniformly over space or time. Thus, scaling up the effects of disturbances requires detailed measurements across multiple spatial scales. To characterize disturbance from wrack we used monthly images from an unmanned aerial vehicle (UAV) in a 144,500 m 2 Spartina alterniflora saltmarsh on Sapelo Island, Georgia (USA), from March 2020 to December 2022. Prior work as well as the results...
A Global Comparison of Direct and Legacy Effects of Drought on Ecosystem ProductivityNARA Subscribed
Terrestrial ecosystems serve as a major carbon (C) sink, but the increasing frequency and intensity of drought threaten the C sink and ecological communities. A comprehensive understanding of the change in ecosystem productivity due to the direct effect versus the legacy effect of drought is still lacking. We quantify the magnitude change in terrestrial gross primary production (GPP) globally due to both direct and long‐term l...
The deep waters of the Gulf of St. Lawrence (GSL) have experienced a significant reduction in dissolved oxygen content during the past decades. One widely documented driver of this deoxygenation is a change in the composition of the deep inflowing water that ventilates the Gulf, which consists of a mixture of warmer, less-oxygenated North Atlantic Central Waters (NACW) and cooler, more-oxygenated Labrador Current Waters (LCW)....
Interpretable deep learning reveals spatiotemporal MRI features of brain aging that align with neurodegenerationNARA Subscribed
Cortical thinning and atrophy are hallmarks of brain aging that have been characterized using magnetic resonance imaging (MRI). Brain aging involves many neuroanatomic features whose effects on brain structure remain unexplored. To address this challenge, we trained interpretable deep neural networks (DNNs) to estimate brain age (BA) from T 1 -weighted ( T 1 w) MRI. By identifying MRI features unapparent to humans, DNNs can fi...
Evaluating MPA success for Caribbean reef fish: the role of design, habitat, and managementNARA Subscribed
Marine protected areas (MPAs) are essential tools for protecting marine ecosystems; yet, their effectiveness varies across regions. In the Caribbean, home to some of the world’s most degraded reefs, evaluating MPA performance requires consistent ecological data and information on management practices. To address this, we conducted standardised reef fish surveys of small (< 20 cm) and large (≥ 20 cm) fish across 83 sites in ten...
SNAPSHOT USA 2024: Year 6 of the Coordinated National Camera Trap Survey of the United StatesNARA Subscribed
Motivation SNAPSHOT USA is an annual, multi‐contributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of speci...