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Detailed geologic mapping and new SHRIMP (sensitive high-resolution ion microprobe) U-Pb zircon, Ar/Ar, Lu-Hf, 14C, luminescence (optically stimulated), thermochronology (fission-track), and palynology reveal the complex Mesoproterozoic to Quaternary geology along the ~350 km length of the Blue Ridge Parkway in Virginia. Traversing the boundary of the central and southern Appalachians, rocks...

Lake Lungo and Lake Ripasottile are two shallow (4-5 m) lakes located in the Rieti Basin, central Italy, that have been described previously as surface outcroppings of the groundwater table. In this work, the two lakes as well as springs and rivers that represent their potential source waters are characterized...

Loss of native grasslands by anthropogenic disturbances has reduced availability and connectivity of habitat for many grassland species. A primary threat to contiguous grasslands is the encroachment of woody vegetation, which is spurred by disturbances that take on many forms from energy development, fire suppression, and grazing. These disturbances are...

Invasive woody plant expansion is a primary threat driving fragmentation and loss of sagebrush (Artemisia spp.) and prairie habitats across the central and western United States. Expansion of native woody plants, including conifer (primarily Juniperus spp.) and mesquite (Prosopis spp.), over the past century is primarily attributable to wildfire suppression, historic periods of intensive...

The 295-300 Ma Petersburg batholith in east-central Virginia forms one of the largest and northernmost of the Alleghanian plutonic complexes in the southern Appalachian Piedmont. The batholith is primarily composed of granite including massive and foliated (both magmatic and solid-state fabrics) varieties. The plutonic complex intruded medium-grade metamorphosed volcanic/plutonic rocks...

Giant Canada geese (Branta canadensis maxima) were extirpated from Iowa by the early 1900s due to unregulated hunting, egg gathering, and wetland drainage in the nineteenth century (Bishop 1978). Ef- forts to reintroduce Canada geese in Iowa began in 1964 (Bishop and Howing 1972) and involved releasing flightless adults and...

No abstract available....

Since the beginning of the 20th century, the overall occupied range of the lesser prairie-chicken (Tympanuchus pallidicinctus) has declined by 84% commensurate with population trends. Much of this decline has been attributed to the loss and fragmentation of native grasslands throughout the lesser prairie-chicken...

Spatial demographic models can help guide monitoring and management activities targeting at-risk species, even in cases where baseline data are lacking. Here, we provide an example of how site-specific changes in land use and anthropogenic stressors can be incorporated into a spatial demographic model to investigate effects on population dynamics...

Many ecosystems continue to experience rapid transformations due to processes like land use change and resource extraction. A systems approach to maintaining natural resources focuses on how interactions and feedbacks among components of complex social‐ecological systems generate social and ecological outcomes. In recreational fisheries, residential shoreline development and fish stocking...

Far-field tsunami records from the Japanese tide gauge network allow the reexamination of the moment magnitudes (Mw) for the 1906 and 1922 Chilean earthquakes, which to date rely on limited information mainly from seismological observations alone. Tide gauges along the Japanese coast provide extensive records of tsunamis triggered by six...

Alewife (Alosa pseudoharengus) and Rainbow Smelt (Osmerus mordax) are the most abundant pelagic planktivores in Lake Ontario (Weidel et al 2017), and the most important prey for salmon and trout, making up greater than 90% of the diet of the top predator, Chinook salmon (Lantry 2001, Brandt 1986), and supporting...

Extreme space weather events are low-frequency, high-risk phenomena. Estimating their rates of occurrence, as well as their associated uncertainties, is difficult. In this study, we derive statistical estimates and uncertainties for the occurrence rate of an extreme geomagnetic storm on the scale of the Carrington event (or worse) occurring within...

Scientific records of temperature and precipitation have been kept for several hundred years, but for many areas, only a shorter record exists. To understand climate change, there is a need for rigorous statistical reconstructions of the paleoclimate using proxy data. Paleoclimate proxy data are often sparse, noisy, indirect measurements of...

Understanding the evolution of passive margins requires knowledge of temporal and chemical constraints on magmatism following the transition from supercontinent to rifting, to post-rifting evolution. The Eastern North American Margin (ENAM) is an ideal study location as several magmatic pulses occurred in the 200 My following rifting. In particular, the...

Choices in ecological research and management are the result of balancing multiple, often competing, objectives. Multi-objective optimization (MOO) is a formal decision-theoretic framework for solving multiple objective problems. MOO is used extensively in other fields including engineering, economics, and operations research. However, its application for solving ecological problems has been sparse,...

Accurate age and growth information is essential in successful management of fish populations and for understanding early life history. We validated daily increment deposition, including the timing of first ring formation, for spotted gar (Lepisosteus oculatus) through 127 days post hatch. Fry were produced from hatchery-spawned specimens, and up to...

This project tested and revised a risk assessment/management tool authored by Moffitt and Stockton designed to provide hatchery biologists and others a structure to measure risk and provide tools to control, prevent or eliminate invasive New Zealand mudsnails (NZMS) and other invasive mollusks in fish hatcheries and hatchery operations. The...

This report synthesizes information on the status of fisheries and aquatic resources in the Prairie Creek sub-basin of Redwood Creek in Humboldt County in northern California, founded on a bibliographic search we conducted of historic and current datasets, unpublished reports, theses, and publications. The compiled Prairie Creek Fisheries Bibliography is...

ContextPlaya wetlands are the primary habitat for numerous wetland-dependent species in the Southern Great Plains of North America. Plant and wildlife populations that inhabit these wetlands are reciprocally linked through the dispersal of individuals, propagules and ultimately genes among local populations.Objective<p id="Par2"...

One of the candidate essential biodiversity variable (EBV) groups described in the seminal paper by Pereira et al. (2014) concerns Ecosystem Structure. This EBV group is distinguished from another EBV group which encompasses aspects of Ecosystem Function. While the Ecosystem Function EBV treats ecosystem processes like nutrient cycling, primary production,...

Thickness of colluvium or regolith overlying bedrock or other consolidated materials is a major factor in determining stability of unconsolidated earth materials on steep slopes. Many efforts to model spatially distributed slope stability, for example to assess susceptibility to shallow landslides, have relied on estimates of constant thickness, constant depth,...

The collection of earthquake testimonies (i.e., qualitative descriptions of felt shaking) is essential for macroseismic studies (i.e., studies gathering information on how strongly an earthquake was felt in different places), and when done rapidly and systematically, improves situational awareness and in turn can contribute to efficient emergency response. In this...

The sagebrush (Artemisia spp.) ecosystem is one of the largest ecosystems in western North America providing habitat for species found nowhere else. Sagebrush habitats have experienced dramatic declines since the 1950s, mostly due to anthropogenic disturbances. The greater sage-grouse (Centrocercus urophasianus) is a sagebrush-obligate species that has experienced population declines over...

Adaptive management is an approach to natural resource management that uses structured learning to reduce uncertainties for the improvement of management over time. The origins of adaptive management are linked to ideas of resilience theory and complex systems. Rangeland management is particularly well suited for the application of adaptive management,...