Articles

The composition of volcanic glass records important clues into the origin and evolution of magmatic systems. However, the analysis of volcanic glass presents challenges when performed using electron-beam techniques, particularly due to Na mobility. While microanalysis of geological materials is usually performed using electron probe microanalyzer-based wavelength-dispersive spectrometry...

Drought is a highly consequential natural disaster that may likely increase in both severity and extent across the conterminous United States (CONUS). The mechanisms affecting the propagation of drought from the atmosphere to streamflow are complex and interactive, making the prediction of streamflow drought difficult with current modeling approaches. Machine learning is an emerging tool...

This study evaluated the use of lidar data to detect streambank erosion and channel incision throughout Raleigh, North Carolina. The study included five components. (1) Generation of lidar-derived rasters, including a digital elevation model of difference that represented channel erosion and positive openness rasters that represented channel incision. (2) Completion of site-based field...

Land-use change and climate variability both regulate land-based inputs of sediment and nutrient delivery to coral reefs, yet few records in Hawaii can identify when these land-based inputs began or how they have evolved through time. We present a 253-year (1760–2013) coral core record from Olowalu reef, Maui, spanning pre-colonial settlement through the rise and decline of sugarcane...

The freshwater mussel genus Obovaria (Bivalvia: Unionidae) has long been recognized as taxonomically challenging due to plastic shell morphology, historical misidentifications, and incomplete geographic sampling across the southeastern United States. Using an integrated approach combining shell morphology, comparative conchology, geographic distribution, and molecular phylogenetic...

Forest demography is difficult to describe accurately. Tree recruitment and mortality are uncommon events, so that rates based on these observations often require long survey periods using large numbers of trees. Demographic rates can scale with tree size, so challenges describing demography are pronounced in coast redwood forests that are dominated by extremely large Sequoia...

Humans have influenced ecosystems for millennia, and social changes can have notable ecological effects. Recent human influence on ecosystems is exemplified by the collapse of fire regimes circa 1900 in the western United States due to increased grazing, fire suppression, and declining Indigenous fire use. Climate can also drive fire regime changes, which is reflected by increasing area...

Reservoir cascades in large river systems impose directional pathways that can structure biological invasions, yet how these pathways interact with propagule supply and lock-mediated passage opportunity to influence arrival timing remains poorly understood. We used interval- and right-censored time-to-event models to evaluate spread dynamics of silver carp (Hypophthalmichthys molitrix)...

Accurate streamflow measurements are essential for hydrologic monitoring, flood forecasting, and water resource management. Traditional in situ methods, although reliable, are often impractical or unsafe during flood conditions or at inaccessible locations. Image velocimetry techniques offer a potential non-contact alternative, yet operational adoption has been hindered by the lack of...

Grassland bird monitoring efforts continue to document population declines in the Great Plains, USA and there is limited understanding of how declines are associated with landscape changes over broad scales. Within Kansas, USA, surveys indicate the resident grassland obligate greater prairie-chicken (Tympanuchus cupido) declined during the past 30 years. Grassland loss has been cited as...

The Brook Trout (Salvelinus fontinalis) is a globally distributed nonnative species that threatens native salmonids in coldwater streams. Understanding the factors regulating Brook Trout densities in coldwater refugia is critical to effective management, so we investigated (a) fine-scale drivers of Brook Trout abundance and (b) factors affecting their thermal sensitivity in 49 coldwater...

Rivers draining continuous permafrost landscapes on the North Slope of Alaska span from the mountains to the coast, integrating gradients in vegetation, soil organic matter, and hydrologic flow. We investigated how these landscape transitions influence dissolved organic carbon (DOC) concentrations, radiocarbon ages, and export along the river continuum over seasonal timeframes in...