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USGS2026

Water volumes, heat flow, and solute discharge from Old Faithful Geyser eruptions, Yellowstone National Park, USA

The iconic Old Faithful Geyser in Yellowstone National Park, USA, has attracted a significant amount of research because of the relative regularity and impressive size of its eruptions. Numerous studies have included observations, measurements, and analyses that informed models of geyser eruptions. However, fundamental quantities, including the associated mass and heat discharged, remain poorly constrained. In April 2025 we measured the volume of water from 45 Old Faithful Geyser eruptions using a portable flume in an outflow channel and specific conductance measurements in the Firehole River. We used high-speed video to perform velocimetry, measured changes in water chemistry to calculate the volume of water evaporated along the outflow channels, and used thermodynamic calculations to estimate the volume of water erupted as steam and to quantify the geyser's heat output. The calculated average volume of water discharged by Old Faithful Geyser in each eruption is 27.9 ± 9.4 m 3 , with no relation between eruption volume and the length of the preceding eruption interval. Video analysis of the eruption's liquid-dominated phase yields similar volumes of 21–30 m 3 . The calculated heat flow from the geyser is 2.2–2.4 MW and the average annual discharge of chloride, fluoride, and arsenic are 63 tons, 3.9 tons, and 241 kg, respectively. Average annual silica deposition rate on the geyser cone and along the outflow channels is 7 tons. This study provides a methodology for future studies at geysers worldwide and a baseline for monitoring future activity changes at Old Faithful.

Wyoming↗

USGS2026

Long-term erosion dynamics and morphological evolution of composite volcanoes: Insights from analogue modelling

Volcanoes undergo rapid growth and extended periods of repose during which erosion dominates, representing natural laboratories for studying erosion patterns and rates across various timescales. However, complex constructional and degradational histories and limited temporal constraints make analyzing volcano erosion dynamics challenging. Analogue models with rainfall-induced runoff offer a simplified and controlled setting to explore volcanic erosion processes and evolution with well-constrained initial cone geometries. This study documents the morphological evolution of analogue volcanoes during rainfall simulation experiments, scaled to reflect natural pristine composite volcanoes. Different cone types, with varied slope profiles and summit craters, are analyzed using photogrammetry-derived digital elevation models with sub-millimeter resolution. Using these models, we quantify the evolution of morphometric parameters, including cone and drainage basin geometries, denudation and erosion rates. Most morphometric parameters and erosion rates show rapid initial variations, followed by more gradual trends. As erosion progresses, the hypsometric integral decreases for cones with initial linear slope profiles and increases for those with concave slopes, highlighting the importance of initial slope profiles in interpreting degrees of erosion. The presence of a summit crater introduces unique erosional processes, shaping wider basins during an initial erosional phase. All cone types develop towards a geometric equilibrium state where the initial diverse morphometric values converge for the hypsometry integral, drainage density, and irregularity index. Initial slope profile and the presence of a summit crater do not significantly affect the topography of the final erosional phase, underscoring the concept of equifinality. These analogue experiments enhance our understanding of real-world volcanic landscape evolution.

Journal of Volcanology and Geothermal Research↗

USGS2026

Petrologic and geochemical characterization of the first year of the 2024–ongoing episodic Halemaumau eruption of Kilauea (Episodes 1–39)

Kīlauea has been erupting episodically since December 23, 2024 (and is ongoing at the time of this writing in 2026) with two consistently active vents in Halema‘uma‘u producing lava fountains ranging in height from 40 to 540 m. In the first year of the eruption (through December 24, 2025, episode 39), the U.S. Geological Survey's Hawaiian Volcano Observatory collected 178 samples for eruption monitoring purposes and used a subset of 80 for near-real-time geochemical analyses. Tephra, lava, and recycled lava lake ooze-out samples have been studied on inter-episode timescales using diverse microanalytical techniques, where research-scale investigations have proven to be advantageous pseudo-near-real-time techniques. Here we present a geochemical and petrologic overview of episodes 1–39 to better understand eruption dynamics and identify changes at Kīlauea following the 2018 summit caldera collapse. There are no significant intra-episode geochemical changes that might be related to variable fountain heights or episode durations, suggesting that eruption dynamics are instead primarily controlled by viscosity and conduit geometry changes throughout a single episode and between episodes. There is variable but clear influence of the still-molten lava lake interior on compositions of this eruption, including in tephra samples from lava fountains, indicating that the vent conduits are connected in some way at depth with the still molten passive lava lake core. Tephra glasses (7.0–7.8 wt.% MgO) show cyclic changes in MgO that were decoupled from lava fountain heights and behavior in episodes 1–28 but positively correlated after episode 29. Additionally, whole-rock and glass compositions are enriched in minor elements such as K 2 O and TiO 2 compared to 2008–2023 summit eruptions, tracking the arrival of a new magma composition that may be related to the prolonged episodic eruptive behavior. Olivine-hosted melt inclusions from five episodes have ~0.35–0.43 wt.% H2O, < 300 ppm CO 2 and < 1500 ppm S, with no significant variations between episodes. Melt and fluid inclusion barometry show that magmas driving these episodes are stored and sourced from the shallow 1–2 km Halemaʻumaʻu reservoir, as were olivine from the 2023 summit eruption. The ongoing episodic eruption also has higher bulk-rock MgO compared to the five previous summit eruptions (2020−2023) and the forsterite (Fo) content of olivine has varied systematically from 2015 to 2025 with the equilibrium olivine composition of the Halema‘uma‘u reservoir increasing from Fo 80.7 in 2015 to Fo 82.7 by 2025. We argue that the Halemaʻumaʻu reservoir is heating up because the rate of magma supply is outpacing effusion and cooling following caldera collapse in 2018.

Hawaii↗

USGS2026

Dismembering the Lava Creek Tuff, Yellowstone volcano

The youngest large explosive eruption of Yellowstone volcano generated the 0.63 Ma Lava Creek Tuff (LCT) ignimbrite and a voluminous, widespread fall deposit accompanying formation of Yellowstone Caldera. The tuff is conventionally divided into members A (LCT-A) and B (LCT-B), defined by a reversal in density/welding profiles and the presence of phenocrystic amphibole in LCT-A. Remapping within the northeastern caldera sector has, however, documented multiple ignimbrites that yield LCT eruption ages but are distinct from documented members A and B. Thus, the framework by which the LCT was originally subdivided is re-examined here using field observations, petrologic analyses, and sanidine geochemistry from LCT-A and LCT-B ignimbrite (as previously mapped) at reference localities around the caldera. Mineral modal abundances in both LCT-A and LCT-B outcrops are dominated by quartz, followed by sanidine, with sizes and abundances that generally increase up-section, as previously documented. Amphibole is found by us, however, only in western and southern sectors, in deposits mapped as both LCT-A and LCT-B, and only as a trace phase. Further, a locality reported as LCT-A with amphibole present yields a sanidine 40 Ar/ 39 Ar date of 0.775 ± 0.002 Ma, precluding any LCT correlation. Ignimbrite samples from mapped LCT-A and LCT-B exhibit variable crystal sizes, sanidine cathodoluminescence image populations and Ba concentrations, with no clear distinction between the mapped members. Collectively this research found no evidence for a definable LCT-A versus LCT-B, meaning that the traditional A and B subdivision does not accurately represent the eruptive architecture of the Lava Creek Tuff and warrants revision.

Idaho, Montana, Wyoming↗

USGS2026

PFAS remediation in a bioelectrochemical system inoculated with the west branch consortium (WBC-2)

Groundwater contamination by per - and polyfluoroalkyl substances (PFAS) poses a persistent environmental and public health concern. This study evaluates a two-chambered bioelectrochemical system (BES) inoculated with the West Branch Consortium (WBC-2) for PFAS remediation. Under an applied cathodic potential of −450 mV (versus Ag/AgCl), the BES with active WBC-2 achieved >99.0% perfluorooctanesulfonic acid (PFOS) removal within 21 days in deionized water with culture medium and > 98.9% removal of PFOS, perfluorooctanoic acid (PFOA), perfluorohexanoic acid (PFHxA), and perfluorohexanesulfonic acid (PFHxS) in contaminated groundwater after 102 days. Intermediate formation (e.g., PFOA, 6:2 fluorotelomer sulfonate (6:2 FTS), perfluoropropionic acid (PFPrA), perfluorobutanoic acid (PFBA)) and background-corrected fluoride release were consistent with PFOS transformation under anaerobic reducing conditions potentially involving defluorination. Following repeated PFOS spikes (100 μg/L on Days 0, 50, and 399), PFOA, PFPrA, and PFBA accumulated over 664 days. Despite being the dominant accumulated compound, PFOA accounted for <1.8% of the total spiked PFOS mass. Minimal PFOS transformation occurred in controls without active WBC-2, highlighting the importance of microbial metabolism. Biofilm analysis revealed dense colonization of rod-shaped bacteria on carbon fiber brushes. Enrichment of Bacillus , Agrobacterium , and other low-abundance taxa suggests selective adaptation to BES and PFAS conditions. These findings highlight BES driven by electrochemically stimulated microbial activity as a promising strategy for PFAS remediation.

Journal of Water Process Engineering↗

USGS2026

Is new actually better? A structural comparison of collaborative governance structures for the management of Atlantic salmon (Salmo salar) in Maine

Collaborative governance structures (CGS) have been increasingly adopted to address joint-jurisdictional management challenges. While the establishment of CGSs has been widely studied, their practical development has remained a conspicuous gap. CGSs are variable systems with several developmental stages (activation, collectivity, and institutionalization) which eventually lead to stabilization, decline, re-creation, or re-orientation. CGSs in decline may need to revisit earlier developmental stages if members choose to re-create or re-orient the structure. The Atlantic Salmon Recovery Framework (ASRF) was the CGS responsible for managing the Gulf of Maine Distinct Population Segment of Atlantic Salmon ( Salmo salar ) from 2011 until 2019 when it was replaced by the Collaborative Management Strategy (CMS) pilot program. The CMS was designed to address concerns identified in the ASRF; 1. slow and ineffective decision-making, 2. confusion surrounding leadership, and 3. low adaptive capacity. Building upon a previous evaluation of the ASRF, we used a parallel design to compare the structural components and participant perceptions of the two structures using a comparative case study methodology. The changes that occurred between the ASRF and the CMS constitute a re-creation, providing a unique opportunity to study this developmental phase of a CGS. The issues observed in the CMS may result from a misalignment between participant expectations and the current developmental stage of the re-created CGS. The CMS reorganized ASRF members and created roles for participants without direct management jurisdiction. The implementation of the CMS addressed many concerns identified in the ASRF while others remained (i.e., high membership uncertainty and confusion surrounding decision-making procedures). Formal leadership roles have created more equal representation, but participants still reported uncertainty regarding status and formalization of non-leadership roles.

Maine↗

USGS2026

Chronic, low concentration pesticide exposure alters reproduction and behavior in the intertidal sea anemone, Anthopleura elegantissima

Widespread pesticide and herbicide use paired with frequent transport away from application sites has led to pesticide presence in nearly all terrestrial and aquatic environments globally. Pesticides have unintentional toxic effects on non-target organisms by interfering with cellular processes, behavior, feeding, reproduction, and disrupting endocrine processes. The aggregating anemone, Anthopleura elegantissima, is an important species along the North American Pacific coast due to its symbiotic relationships that contribute to high productivity, and its clonal abundance that structures the rocky intertidal habitat. Commonly used pesticides, atrazine, diuron, and carbendazim were previously detected in coastal waters of Oregon, U.S.A. This study examined the potential effects of these pesticides at environmentally relevant concentrations on reproduction, symbionts, and behavior of A. elegantissima over an eight-week period. Pesticides significantly decreased gonad development in all treatments, having the most significant effect in individual treatments of atrazine ( p = 0.003) , carbendazim ( p = 0.003) , and the mixture of all three pesticides ( p = 0.008). All pesticide treatments significantly increased cloning behavior compared to the control, suggesting that cloning could be a stress response. Pesticide exposure also significantly increased tentacle retraction movement, suggesting possible metabolic or energy impairments. While other studies have previously found behavioral changes in anemones due to pollutants, our study is the first to document behavioral changes in anemones from pesticide exposure. All three pesticides significantly impacted a non-target marine invertebrate at environmentally relevant concentrations, which underscores the value of studies that focus on effects on marine invertebrates, paired with comprehensive pesticide monitoring in coastal areas.

Oregon↗

USGS2026

Ecotoxicological profile of a high prevalence marine disease area in Florida's Gulf coast

Pervasive marine pollution can have devastating effects on ocean health. Polychlorinated Biphenyls (PCB), Polycyclic Aromatic Hydrocarbons (PAH), and Organochlorine Pesticides (OCP) are of particular concern given their high level of toxicity and carcinogenicity. These compounds originate from anthropogenic activity, therefore are often ubiquitous in coastal environments close to human sources. Marine turtles in coastal Florida (USA) are affected by fibropapillomatosis, a tumor-causing panzootic with highly debilitating symptoms. Despite repeated associations between fibropapillomatosis occurrence and carcinogenic pollution, the ecotoxicological status of high disease areas in the Florida Gulf has been unknown. Our study deployed passive sampling devices along a structured inshore-to-offshore coastal grid to generate the first comprehensive dataset on the concentration and diversity of oncogenic pollutants in Crystal River, Florida, where juvenile green turtles exhibit a fibropapillomatosis prevalence of 74%. Multiple OCP, PAH, and PCB compounds were detected for a total chemical concentration of 16,086.98 pg/L (Σ OCP 45.51 pg/L + Σ PAH 16,014.53 pg/L + Σ PCB 26.94 pg/L). Density and composition of carcinogenic pollution was found to be significantly lower in offshore green turtle habitats compared to inshore habitats (p=0.02), suggesting multiple potential contamination sources along the coastline. The carcinogenic compounds detected have been shown to have associations with fibropapillomatosis in other parts of the world, as well as having wider ecosystem implications. Our work contributes to the body of knowledge correlating the emerging threat of harmful ocean pollution and marine wildlife diseases.

Florida↗

USGS2026

Statewide agent-based model for management of chronic wasting disease in white-tailed deer: PAOvCWD

Chronic wasting disease (CWD) is an always-fatal disease infecting wild cervids globally. Ecologically and economically important, CWD presents a challenge for managing white-tailed deer ( Odocoileus virginianus ). We built an agent-based model to simulate CWD transmission and assess potential management actions that could slow disease spread: PAOvCWD . We developed PAOvCWD using contact rates and other behavioral and ecological metrics estimated from deer monitored in Pennsylvania, USA. We programmed potential management responses (e.g., culling, altered hunter harvest) for all 22 Pennsylvania wildlife management units and validated the efficacy of PAOvCWD using a deer population in south-central Pennsylvania infected with CWD for > 10 years. To support applications of our model, we developed a user-friendly R pipeline that allows implementation with relatively minor modifications. Our pipeline includes four steps: • Steps 1 and 2 generate regional percent forest cover rasters and curate population-level demographics. • Step 3 initializes landscapes and agents using our PAOvPOP model. • Step 4 assesses CWD transmission and management responses using our PAOvCWD model.

Pennsylvania↗

USGS2026

Generating geochemical and mineralogy distributions of soil in the conterminous United States using Bayesian hierarchical spatial models

Characterizing geochemical and mineralogical soil distributions across large spatial extents is essential for understanding mineral resources, ecosystem processes, and environmental risks. Rasters of soil geochemical distributions for the conterminous United States, however, are limited. We present a Bayesian modeling workflow and tool for generating predictive geochemical and mineralogy distribution maps for the conterminous United States using integrated nested Laplace approximation (INLA) with the stochastic partial differential equation approach. By modeling soil geostatistical data with environmental covariates (soil properties, topography, climate, and land cover), we generate predictive distributions of soil geochemistry that can be mapped or extracted for further analyses. As an example, we model the spatial distribution of trace elements in soil relevant to vertebrate health (cobalt, copper, iron, manganese, selenium, and zinc) and provide a workflow that can be used to generate and visualize predictive distributions of 39 other major and trace elements and 21 minerals of the soil survey, supporting a variety of ecological, environmental, and agricultural applications.

MethodsX↗

USGS2026

Climate-smart wetlands can mitigate the wetland-methane feedback loop

Climate change is intensifying wetland methane emissions, reinforcing a feedback loop that accelerates warming and threatens wetlands’ role as natural climate solutions. We propose climate-smart interventions for wetland protection, restoration, and management that explicitly account for methane dynamics. Targeted interventions can weaken methane feedback while safeguarding ecological functions and services.

One Earth↗

USGS2026

Constraining the onset of carboniferous cyclicity in the Arkoma Basin of the Midcontinent, North America: Implications for calibrating a globally significant latest Bashkirian transgression

Cyclothems are defined by the repeat juxtaposition of littoral and open marine successions over short stratigraphic distances (meters to 10's of meters) and are interpreted to be driven by glacioeustatic forcing of sea level during the late Paleozoic Ice Age. The concept of cyclothems was defined in the Midcontinent region of the United States. However, correlating the Midcontinent region to other cyclic successions is difficult, which is the result of no geochronologic control for the Midcontinent biostratigraphic framework. We present the first high-resolution U Pb zircon CA-ID-TIMS and feldspar 40 Ar/ 39 Ar age control for the onset of Midcontinent cyclothem deposition in the Arkoma Basin, Arkansas USA. Geochronologic control is obtained from a volcaniclastic unit preserved in the newly recovered Dare Creek #1 core. We integrate these data with biostratigraphic, lithostratigraphic and trace element analyses to investigate the timing, stratigraphic and geochemical response to late Paleozoic climate forcing. The lowermost Atoka Formation is associated with the onset of five high frequency transgressive-regressive cycles, which are defined by nearshore sandstones juxtaposed on top of offshore marine mudstones and are associated with changes in salinity and redox conditions. The Trace Creek Member of the lower Atoka Formation hosts a thick, organic-rich black shale, which defines the last and maximum transgression of the lower Atoka Formation in the Arkoma Basin, in the latest Bashkirian. Base-level records from time equivalent stratigraphic successions from Arrow Canyon, Nevada, U.S.A. and the Donets Basin, Ukraine also record a maximum transgression in the latest Bashkirian. The synchroneity of maximum flooding events from multiple basins which span the low latitudes in the latest Bashkirian support that cyclothem deposition was controlled by allostratigraphic forcing mechanisms, likely glacioeustatic forcing resulting from dynamic glaciation in high-latitude Gondwana.

Arkansas, Oklahoma↗

USGS2026

Challenges and opportunities for Sendai framework disaster loss reporting in the United States

The Sendai Framework for Disaster Risk Reduction provides quantitative indicators for nations to measure progress in the reduction of disaster losses. The collection and analysis of disaster loss data under the Sendai Framework improves our understanding of the effectiveness of national disaster risk reduction strategies and interventions. The Sendai Framework has enhanced cooperation among Federal agencies to collect and track disaster loss data in the U.S., yet challenges remain for reporting disaster losses. Based on our experiences collecting and reporting U.S. data to the Sendai Monitor, we identify opportunities to improve disaster loss reporting in the U.S.

Progress in Disaster Science↗

USGS2026

Can a physics-based fire behavior model predict burn severity and post-fire debris flow hazard?

Post-wildfire flooding and debris flows pose a threat to ecosystems and infrastructure. As the frequency and size of severe wildfires increase, there is a growing need for predictive debris flow hazard modeling in unburned but fire-prone landscapes. However, no crosswalks have been established between physics-based models of fire behavior and the remotely sensed burn severity inputs needed for debris flow modeling. Here, we explore this connection by creating a large ensemble of fire behavior simulations using QUIC-Fire – a fast-running three-dimensional fire model – in basins across five major-disaster wildfires in California and Washington. We then conducted generalized linear mixed modeling (GLMM) and Random Forest modeling to identify QUIC-Fire outputs that best predicted remotely sensed burn severity. We found that the selected linear predictors exhibited weak and unintuitive relationships with soil burn severity and differenced Normalized Burn Ratio. Moreover, model evaluations of GLMMs and Random Forests showed they were poorly predictive of both metrics of remotely sensed burn severity. This suggests that there are barriers to integrating QUIC-Fire into a wildfire-hazards modeling framework, which could include mismatches in scale between fire models and remotely sensing, or simplifications of weather data and fire initiation. Further research is needed to establish connections between the fire physics outputs of QUIC-Fire and post-fire effects to vegetation and soils that are essential for evaluating debris flow hazard.

California, Washington↗

USGS2026

Cyanobacteria and aquatic ecosystem dynamics across 28,000 years of environmental changes in subtropical North America

Ecological pressures on aquatic ecosystems have increased over recent centuries due to human activities and climate change. However, contextualizing ecosystem deterioration is often challenging due to limited knowledge of environmental changes over millennial timescales. Subtropical Carolina bays in North Carolina, USA, have remained unglaciated, preserving paleolimnological records that extend back to the last glacial period. Here, we analyzed a sediment core from the ecologically rich Lake Waccamaw spanning more than 28,000 years for aquatic proxies of nutrients, photosynthetic pigments, cyanotoxins, carbon isotopes, and terrestrial proxies of pollen and charcoal. The study explored paleolimnological changes in the aquatic environment connected to land changes and climate during the late Quaternary in the southeastern Atlantic Coastal Plain. Results reveal that while current levels of colonial cyanobacteria are high, past levels of cyanobacteria, other primary producers, and cyanotoxins were higher under natural climate variability. Abrupt ecosystem responses to increasing trophic conditions during Interstadial 3 (27.8–26.4 cal ka BP) and the early Holocene (11.4–7 cal ka BP) were marked by increases in primary producer abundance, deciduous vegetation expansion, and fire activity. Cyanobacteria remained dominant throughout the record, with colonial forms prevailing during the Holocene. Increases in pigment concentrations aligned with Quercus and were primarily driven by hydroclimatic variability and nutrient stoichiometry. Transitions between Pinus and Quercus pollen matched stadials and interstadials in the δ 18 Ο record from the North Greenland Ice Core Project (NGRIP). This study highlights the value of multi-proxy millennial-scale paleolimnological records for understanding aquatic ecosystem responses to climate conditions during the late Pleistocene.

North Carolina↗

USGS2026

Cultural pollen delivery is not needed to account for consistent, trace abundances of Zea mays pollen in the sediments of Santa Fe Lake

Roos (2026) proposes an intriguing cultural mechanism to account for the rare (<1.5% of terrestrial pollen), but consistent (28/34 samples spanning 450 years), presence of Zea mays (maize) pollen in the sediments of Santa Fe Lake from 800 to 350 cal yr BP (1150 – 1600 cal yr CE; Henne et al., 2026a, 2026b). Whereas the importance of maize agriculture to Ancestral Puebloans is well established, Roos argues that the near-absence of maize pollen from soils proximate to historical maize cultivation and in peat or lake-sediment records in the Southwestern USA indicates that natural pollen delivery was not sufficient to account for the trace abundances of maize pollen we counted at Santa Fe Lake. Roos concludes that ceremonial practices provide an alternative mechanism that should be considered in the interpretation of lake-sediment archives like Santa Fe Lake. We agree that the cultural practices described by Roos are a credible source of pollen delivery and understand the significance of sacred lakes to Indigenous communities (Bodine, 1988). However, we conclude that natural delivery to the Santa Fe catchment is sufficient to account for the trace abundances of maize pollen in our record. We first place our consistent finding of maize pollen in a context beyond the Southwestern USA that includes other mountain regions, discuss why it is unlikely to find consistent maize pollen in the records presented by Roos, and expand on what makes Santa Fe Lake a superior archive for maize pollen than previous records. Based on this discussion, we conclude that natural pollen deposition is the most parsimonious explanation for consistent maize pollen over a period of 450 years.

New Mexico↗

USGS2026

Comparing spatial covariance to common field vegetation metrics

Spatial covariance is a metric used to delineate grassland cores and track state transitions driven by woody encroachment in rangelands, and it does so by calculating the degree of spatial coexistence between functional groups like grasses and trees at different scales. Spatial covariance is being used in biome-scale frameworks aimed at combatting woody plant encroachment and grassland conservation, but little is known about how spatial covariance relates to on-the-ground vegetation metrics. Here, we begin to address this knowledge gap by comparing tree-grass spatial covariance (0.81 ha scale) to a variety of established, field vegetation structure metrics. Generalized additive models revealed that relationships between spatial covariance and field-based vegetation metrics were weak to moderate (deviance explained ranging from 10% – 47%). Tree density had the strongest relationship with spatial covariance (deviance explained = 47%): tree density nonlinearly decreased to near-zero when spatial covariance became positive. Average visual obstruction and visual percent grass cover had the weakest relationships with spatial covariance (deviance explained = 13% and 10%, respectively). The stronger tie between tree density and spatial covariance and the very weak link between dominant vegetation cover aligns with the intended usage of spatial covariance in rangeland management, which is to locate treeless grassland cores (i.e., spatial covariance values near zero) and prioritize them for defending “core” rangeland habitats. This also aligns with current applications of spatial covariance in grassland conservation as a metric of early warning, variation, intactness, and boundary strength, not of central tendencies or dominance. Additional testing at different scales and in different ecosystem contexts will help to further understand how spatial covariance relates to other field vegetation metrics.

Arkansas↗

USGS2026

Spatial variation in effectiveness and costs of sagebrush restoration treatments across the western United States

Natural resource managers strive to improve restoration efficiency across the vast network of public lands of the United States, seeking the best return on investment through innovation, geographic prioritization, and adaptive management. This challenge is exemplified by ecosystems dominated by sagebrush ( Artemisia spp.), which occur across the western United States and have been degraded by increasing wildfire frequency driven by invasive plant spread, among other factors. However, both costs and effectiveness of sagebrush restoration can vary spatially due to management practices in addition to biotic and abiotic factors, and characterizing this variation could inform broad-scale planning. We leveraged published models of sagebrush recovery and treatment costs to predict and evaluate cost-effectiveness of aerial and drill seeding Artemisia spp. across 429 718 km 2 that overlapped 12 US states. Compared to natural recovery, effectiveness for both methods was generally low, yet effectiveness was often greater, and costs were always greater, for drill than aerial seeding, resulting in slightly higher cost-effectiveness on average for drill seeding. Cost-effectiveness for both treatments increased near major roads and in areas with more repeated burns. Cost-effectiveness also increased with predisturbance cover of sagebrush but decreased with herbaceous cover. However, we also identified areas where aerial seeding was more cost-effective than drill seeding, particularly with greater slope. Our results provide spatially explicit estimates and potential mechanisms of cost-effectiveness for two common seeding methods for sagebrush, which can help prioritize limited resources, guide land use, and improve restoration efficiency and effectiveness across public rangelands of the western United States.

western United States↗