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Dryland ecosystems are particularly vulnerable to erosion generated by livestock grazing. Quantifying this risk across a variety of landscape settings is essential for successful adaptive management, particularly in light of a changing climate. In the Upper Colorado River Basin, there are...

Knowledge of vulnerability provides the foundation for developing actions that minimize impacts on people while maximizing the sustainability of ecosystem goods and services. As a result, it is becoming increasingly important to determine how resource-dependent people are vulnerable to environmental hazards. This is particularly true in coastal Louisiana where the...

Assessing the sensitivity of groundwater systems to hydroclimate variability is critical to sustainable management of the water resources of Guam, US territory. We assess spatial and temporal variability of isotopic and geochemical compositions of vadose and phreatic groundwater sampled from cave drip sites and production wells, respectively, to better understand the vulnerability of the...

Individuals should prefer and use habitats that confer high fitness, but habitat use is not always adaptive. Vegetation in natural landscapes changes gradually and the ability of species to adaptively adjust their habitat use to long-term changes is largely unstudied. We studied nest patch and territory use over 28 yr...

Partial differential equations (PDEs) are a useful tool for modeling spatiotemporal dynamics of ecological processes. However, as an ecological process evolves, we need statistical models that can adapt to changing dynamics as new data are collected. We developed a model that combines an ecological diffusion equation and logistic growth to...

Change-point, or step-trend, detection is an active area of research in statistics and an area of great interest in hydrology because change points may be evidence of natural or anthropogenic changes in climatic, hydrologic, or landscape processes. A common change-point technique is the Pettitt test; however, many change-point methods are...

An understanding of the applicability and utility of hydrologic models is critical to support the effective management of water resources throughout the Southeastern United States (SEUS) and Puerto Rico (PR). Hydrologic models have the capacity to provide an estimate of the quantity of available water at ungauged locations (i.e., areas...

This chapter provides a general review of grazing disturbance by large mammalian grazers and the role of ecological context in moderating its effects, with emphasis on North American deserts. It discusses the ecological consequences of cessation of livestock grazing and present a case study from the Mojave Desert, United States...

Species endemic to alpine environments can evolve via steep ecological selection gradients between lowland and upland environments. Additionally, many alpine environments have faced repeated glacial episodes over the past two million years, fracturing these endemics into isolated populations. In this “glacial pulse” model of alpine diversification, cycles of allopatry and...

Visual and olfactory stimuli induce behavioural responses in fishes when applied independently, but little is known about how simultaneous exposure influences behaviour, especially in downstream migrating fishes. Here, downstream moving juvenile sea lamprey (Petromyzon marinus) were exposed to light and a conspecific chemosensory alarm cue in a flume and movement...

Occupancy patterns can assist with the determination of habitat limitation during breeding or wintering periods and can help guide population and habitat management efforts. American black ducks (Anas rubripes; black ducks) are thought to be limited by habitat and food availability during the winter, but breeding sites may also limit...

Introduced Utah Chub Gila atraria were first sampled in Henrys Lake, Idaho, in 1993, and their presence in the system is a concern given possible interactions with sport fishes. Our objective was to describe the population dynamics of Utah Chub in Henrys Lake. A total of 362 Utah Chub was sampled via...

We compared near-fault velocity spectra recorded during laboratory experiments to that of natural earthquakes. We fractured crystalline rock samples at room temperature and intermediate confining pressure (50 MPa). Subsequent slip events were generated on the fracture surfaces under higher confinement (300 MPa). Velocity spectra from rock...

Linking fault behavior over many earthquake cycles to individual earthquake behavior is a primary goal in tectonic geomorphology, particularly across an entire plate boundary. Here, we examine the 1150-km-long, right-lateral Queen Charlotte-Fairweather fault system using comprehensive multibeam bathymetry data acquired along the Queen Charlotte Fault (QCF) offshore southeastern Alaska and...

South Florida resource management, particularly the Everglades restoration effort, is beginning to consider projections of precipitation from multiple climate models for decision-making. Because precipitation changes can significantly affect the Everglades ecosystem, characterization of precipitation projection uncertainty is important for resource management decisions, and reduction of uncertainty is desired for...

AimPredicting distributions is fundamental to ecology, yet hindered by spatially restricted sampling, scale-dependent relationships and detection error associated with field surveys. Predictive species distribution models (SDMs) are nonetheless vital for conservation of many species. We developed a framework for building predictive SDMs with multi-scale data and used...

Coastal systems in the Gulf of Mexico are threatened by reduced sediment supply, storm impacts and relative sea-level rise (RSLR). The geologic record provides insight into geomorphic evolution thresholds to these forcing mechanisms to help predict future barrier evolution in response to climate change. This study synthesizes ∼2100 km of...

Degradation of wetland ecosystems has negatively impacted many species, perhaps none more so than marsh birds that breed in vegetative emergent wetlands throughout North America. The U.S. Department of Defense manages approximately 29 million acres of land within the continental U.S., and many military installations contain wetland complexes that may...

Runoff increases after wildfires that burn vegetation and create a condition of soil-water repellence (SWR). A new post-fire watershed hydrological model, PFHydro, was created to explicitly simulate vegetation interception and SWR effects for four burn severity categories: high, medium, low severity...

The recovery of natural ecological processes after disturbance is poorly understood. Some disturbances may be so severe as to set ecosystems onto a new trajectory. The Canaan Valley National Wildlife Refuge in West Virginia protects a unique high-altitude wetland that was heavily disturbed by logging 100 years BP and...

The New Madrid seismic zone of the central United States is an intraplate seismic zone with blind structures that are not seismically active but may pose seismic hazards. The Joiner Ridge fault is the 35 km long east-bounding fault of the Joiner Ridge blind horst located in eastern Arkansas approximately...

Land use/land cover (LULC) change has significant impacts on nutrient loading to aquatic systems and has been linked to deteriorating water quality globally. While many relationships between LULC and nutrient loading have been identified, characterization of the interaction between LULC, climate (specifically variable hydrologic forcing) and solute export across seasonal...

More data are being collected about the world around us than ever before, but effectively using this information requires different data stores to be integrated in such a way that they can be seamlessly queried and analyzed. Automated alignment algorithms exist to facilitate this data integration challenge. In this paper...

The Clear Lake Hitch is an imperiled minnow endemic to Clear Lake, Lake County, California, USA that is listed as threatened under the California Endangered Species Act (ESA) and is a candidate for listing under the United States ESA. It exhibits a potamodromous life cycle whereby adults, which reach...

The clupeid gizzard shad Dorosoma cepedianum is often the most abundant fish species in North American reservoirs, and this dominance can have cascading trophic effects on entire fish assemblages. Accordingly, a key aspect of managing reservoir fish assemblages involves controlling gizzard shad densities. We used a...