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At least 883 records · Page 49Linked to original sources
USGS2026

Variability and consistency in wildfire susceptibility: Insights from a national compilation

Background Wildfire risk in the United States is rising and remains a land management priority. The quantitative wildfire risk assessment (QWRA) framework integrates fuels, topography, weather and values at risk to estimate the potential change in value from wildfire. Within this, response functions (RFs) represent how values respond to fire intensity. These are often based on expert judgment, but variation across assessments is unclear. Aims This study uses data from the US Geological Survey (USGS) Wildfire Hazard and Risk Assessment Clearinghouse to characterize consistency and variation across categories and contexts. Methods We applied descriptive statistics to summarize RFs, using tables, box-and-whisker plots and heat maps stratified by highly valued resource or asset (HVRA) category and spatial scale. Key results RFs and value definitions vary, especially for ecosystem-related resources. Some functions, such as for buildings in the wildland–urban interface (WUI), translate well across contexts, while others require more input. Conclusions Some functions are broadly transferable, while others need customization. This analysis provides references and starting points for improvement to RFs in QWRAs. Interpretations Expanding the clearinghouse and dataset and building more transparency in expert elicitation can build trust among communities, agencies and end-users, and can support efficient use of limited resources to mitigate wildfire risk.

International Journal of Wildland Fire↗
USGS2026

Oak masting breaks down in a highly fragmented, pollen limited landscape

Masting, the production of variable and synchronous seed crops, is common among wind pollinated trees, and periodic pollen limitation is thought to be an important component of the process of masting. However, little is known either about the dynamics of mast seed production or pollen limitation in isolated trees. We tracked seed production of valley oak ( Quercus lobata ) over 11 years in a highly fragmented landscape in California’s Central Valley in which many trees lacked conspecific neighbors within 500 m. We found that oaks with closer neighbors produced more acorns on average than oaks with fewer neighbors. Consistent with theories linking mast seeding and pollination, the isolation effect was most apparent in the highest seed production years. While individual trees showed substantial interannual variation in seed production, we observed little synchrony in seed production among individuals compared to intact oak populations throughout California. Our results indicate that highly fragmented populations suffer signs of pollen limitation and do not produce synchronous seed crops. Fragmentation, alongside climate change, is a dimension of global change that interrupts the typical seed production dynamics of trees.

California↗
USGS2026

PDCD-DAT: A global database of pyroclastic density current deposit field data

Pyroclastic density currents represent one of the deadliest hazards posed by active volcanoes. Analysis of their deposits provides valuable insights into their internal dynamics and informs numerical simulations of pyroclastic density currents which underpin many volcanic hazard assessments. We present PDCD-DAT, a global database of pyroclastic density current deposit characteristics compiled from peer-reviewed literature. The database includes both quantitative datasets (e.g., grain size, density, bedform dimensions, thickness) and qualitative descriptors (e.g., sedimentary structures, lithofacies). PDCD-DAT includes data from 85 source publications, covering 97 eruptions or eruptive phases, and 214 individual depositional units from 55 globally distributed volcanoes. Eruptions recorded in the database range from VEI 1–8. We highlight examples of potential applications of the database, which include (i) comparison of single deposit case studies to global datasets, (ii) informing input parameters and conditions for numerical and analogue models of pyroclastic density currents, (iii) validation of numerical and analogue models against a wide variety of natural case study deposit architectures, and (iv) estimating hazard impact metrics of pyroclastic density currents from past eruptions. We show that the database represents a useful tool for improving our ability to model pyroclastic density currents, predict their associated hazards, and understand the relationships between the internal dynamics of pyroclastic density currents and the properties of their deposits. PDCD-DAT is integrated with the FlowDat Mass Flow Database, which provides a sustainable platform for the database. We aim for PDCD-DAT to be expanded in the future through addition of pyroclastic density current deposit datasets from new field studies conducted by the volcanology research community.

Journal of Applied Volcanology↗
USGS2026

Not so fatal attraction: Captive female Burmese Python lures do not improve wild python detection

The ongoing invasion of Python bivittatus (Burmese Python; henceforth, Python) across the Greater Everglades Ecosystem (GEE) has led to near total collapse of the affected mammal community over the past few decades. Management efforts to eliminate Pythons and control their spread have been hampered by the Python's low detectability, which may be improved by using a lure. In controlled settings, male Pythons show an attraction to the scent from reproductively active females. To test the effectiveness of using reproductively active female Pythons as a lure for attracting wild male Pythons in the field, we conducted a paired experiment with wild-caught female Pythons in pens and empty control pens. We monitored Python visitation at all sites using camera traps, which resulted in >3,000,000 photographs that we filtered to 4 independent detections of Pythons using AI software. Python detection was low at sites with female Pythons (3 observations) and control sites (1 observation) over 90 days at 12 sites. Stress associated with captivity may have halted reproductive females from producing pheromones, eliminating the chemosensory cue that lures males. Identifying and implementing husbandry techniques to reduce stress in wild-caught female Pythons could improve the effectiveness of this technique. Little is currently known about the chemical ecology of Pythons, and pheromonal communication in particular, and further research in this area could aid in the identification and production of effective, low-cost lures to increase detection and removal of this invasive species.

Florida↗
USGS2026

Temporal and spatial changes in seismic attenuation associated with inferred fluid migration in the 2016 central Apennines earthquake sequence

Prior work suggests that high‐frequency seismic attenuation acts as a highly sensitive proxy for crustal permeability and fluid mobility in fractured media. We test the hypothesis that the fault system responsible for the 2016–2017 Amatrice–Visso–Norcia–Capitignano sequence acted as an impermeable seal, compartmentalizing pressurized fluids until dynamic rupture triggered widespread fluid diffusion. By tracking across the sequence the spatiotemporal evolution of the S ‐wave anelastic attenuation parameter, we identify large, positive low‐frequency attenuation anomalies emerging within the hanging wall following the Amatrice mainshock and strictly preceding subsequent large ruptures. Conversely, we observe weaker, negative anomalies in the footwall, anticorrelated in time with those of the hanging wall, revealing a massive asymmetry in fluid redistribution and permeability evolution across the fault system. Furthermore, aftershock migration rates reveal distinct linear alignments in a distance‐reduced time space, allowing us to explicitly track and quantify episodes of lateral and upward fluid migration. These physically consistent patterns suggest that stress‐driven fluid diffusion directly weakens adjacent fault patches, dictating the spatiotemporal migration of seismicity. We conclude that near‐real‐time monitoring of seismic attenuation may help detect fluid redistribution in active fault systems and may provide useful information for time‐dependent seismic hazard assessment.

central Apennines↗
USGS2026

Simulation of groundwater flow to evaluate hydrogeologic controls on a PFAS plume, Coakley Landfill Superfund site, Rockingham County, New Hampshire

Per- and polyfluoroalkyl substances (PFAS), including perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), have been detected at combined concentrations above 2,000 nanograms per liter (ng/L) at groundwater seep locations near the Coakley Landfill Superfund site, in North Hampton, New Hampshire. The landfill was active from 1972 to 1985. An impermeable cap was placed on the landfill in 1998. The adjacent area to the Coakley Landfill has many water supply wells, and transport of PFAS compounds to the wells is a concern. Fracture anisotropy in the underlying bedrock aquifer complicates the understanding of PFAS transport because groundwater preferentially travels along fractures that may not align with the prevailing groundwater flow direction. In 2018, the U.S. Environmental Protection Agency and the U.S. Geological Survey began an investigation of the groundwater flow from the Coakley Landfill site. This report describes the modification of a numerical groundwater-flow model for the local area around the Coakley Landfill and summarizes findings of the investigation. In addition, this report includes a brief description of PFOA and PFOS occurrence, a discussion of model construction, evaluation of model performance through calibration, and discussion of simulation results for two periods (before and after capping). Limitations are also discussed. Results show that simulated groundwater flow moves from the Coakley Landfill to the west and north. Advective transport modeling using particle tracking shows that groundwater from the landfill discharges primarily to streams to the west and north, and a small amount is transported to distal wells. Dilution of contaminants through advection and dispersion likely plays a role in whether PFAS compounds from the landfill will be detected above laboratory reporting levels at distal wells.

New Hampshire↗
USGS2026

Hydrogeologic framework and conceptual groundwater-flow model of the panhandle and northwest parts of the High Plains (Ogallala) aquifer in Oklahoma, 1998–2022

This study was conducted by the U.S. Geological Survey, in cooperation with the Oklahoma Water Resources Board, to update the hydrogeologic framework and conceptual flow model for the panhandle and northwest parts of the High Plains (Ogallala) aquifer in Oklahoma, which together compose the Ogallala aquifer focus area. The study included the construction of a potentiometric surface, and available geologic and hydrologic data were used to evaluate saturated thickness of the aquifer. The water budget for the updated conceptual groundwater-​flow model was based on estimated inflows and outflows for the 1998–2022 study period. Saturated thickness of the Ogallala aquifer averaged 127 and 116 feet for the panhandle and northwest parts, respectively. Groundwater withdrawals from the Ogallala aquifer for 1998–2022 averaged 422,054 and 39,645 acre-feet per year (acre-ft/yr) for the panhandle and northwest parts, respectively. Recharge, the primary inflow, was estimated at 0.63 inch per year for the 1998–2022 study period, with the panhandle part of the Ogallala aquifer receiving 175,068 acre-ft/yr and the northwest part of the Ogallala aquifer receiving 49,376 acre-ft/yr. Additional inflows included irrigation return flows, estimated at 8,111 and 642 acre-ft/yr for the panhandle and northwest parts, respectively, of the Ogallala aquifer. Net lateral groundwater flows, considered to be aquifer outflows, were estimated to account for 31,908 acre-ft/yr for the Ogallala aquifer focus area. Streambed seepage, which was an outflow of 5,535 acre-ft/yr, was only present in the northwest part of the Ogallala aquifer. Vertical leakage and saturated-zone evapotranspiration were considered negligible outflows. These findings provide a revised conceptual groundwater-flow model water budget for the Ogallala aquifer focus area in Oklahoma.

Colorado, Kansas, Oklahoma, Texas↗
USGS2026

Hazard potential of compound flooding from rainfall, storm surge, and groundwater in coastal New York and Connecticut

Compound flood events, the co-occurrence of multiple flood drivers, can result in flood hazard potential exceeding that of any single driver alone. To evaluate compound flooding in a semi-urbanized coastal area, historical records dating back to 1970 are used to study the co-occurrences of high precipitation, storm surge, and shallow groundwater conditions along the coastlines of New York and Connecticut. Joint return periods for coincident precipitation-surge events were computed using statistical dependence models and compared to the assumption of independence as a ratio, referred to here as a return period adjustment. Results indicate distinct seasonality where compound events in the area disproportionately occur in the cold season between October and April. Return period adjustments range from a factor of 1 to almost 9, demonstrating the range in precipitation-storm surge dependence across the study area. Across all 24 station triad locations, groundwater levels were elevated during times of precipitation- surge co-occurrence, reflecting the tendency for coastal storms and shallow groundwater conditions to co-occur seasonally. The result is a pseudo-trivariate compound flood hazard score and corresponding hazard map that integrates dependence between daily precipitation-surge events and overall monthly groundwater levels (as a precondition) into a relative compound hazard score. The location with the highest compound flood hazard score is on the south shore of Long Island, as well as locations across coastal Connecticut where groundwater levels compound the co-occurrence of heavy precipitation and storm surge.

Connecticut, New York↗
USGS2026

Space between houses influences movement and habitat selection of ungulates: Width as a novel metric of development

Wildlife often lose access to habitat due to housing development. The magnitude of indirect habitat loss can be conditional on the configuration of individual houses, but commonly used metrics (i.e. density or distance) can overlook the configuration of development. We introduce a novel framework to index the configuration of development based on the width of space between houses and associated structures. We use resource selection functions to assess the degree that GPS-collared elk ( Cervus canadensis ), mule deer ( Odocoileus hemionus ), pronghorn and moose ( Alces alces ) on winter range and on migration routes use space between houses within northwest Wyoming, USA, near the towns of Cody and Jackson. Further, to help inform regulations aiming to promote wildlife movement across a gradient of land uses, we differentiated between individuals residing in primarily rural and exurban areas. Rural populations of elk, mule deer, pronghorn and moose avoided spaces narrower than 2 km and never used spaces narrower than 50 m between houses, whereas exurban populations of elk, mule deer and moose selected for spaces narrower than 2 km but avoided spaces narrower than 50 m. We identified cutoffs in rural and exurban areas where space may become too narrow for most animals to use. Through this metric, managers and policy makers can inform the necessary width to maintain wildlife movement through corridors. Our width metric can be applied to other systems and our workflow is publicly available ( https://wildlifemovetools.org/width-calculator ) so users can estimate the width of space between structures in their focal areas. Synthesis and applications . In rural areas, maintaining spaces between houses >500 m will likely facilitate ungulate movement. To fully conserve functional habitat, such as unimpeded habitat use along migration corridors, maintaining spaces approximately >2.5 km between houses will likely be necessary.

Wyoming↗
USGS2026

Lava flow emplacement dynamics during the Mauna Loa 2022 eruption

On November 27, 2022, Mauna Loa erupted for the first time in 38 years, threatening a major highway on the Island of Hawaiʻi. The opening phases of the eruption were focused at the volcano’s summit, before magma propagated into the upper Northeast Rift Zone to erupt at four fissure segments that localized at fissure 3 by December 2. This fissure produced a braided ʻaʻā flow that traversed the steep north flank at >1 km/hr, before slowing as slopes shallowed. Effusion rates peaked in the early hours of the eruption and then steadied at around 100 m3/s at fissure 3. Lava effusion became variable and dropped abruptly on December 7. The eruption ended on December 10 with a final flow length of 18 km. We tracked lava effusion rates, flow advance, channel dynamics, and 3-D flow field development with field and remote sensing observations throughout this eruption to inform lava flow forecasts and investigate ʻaʻā flow dynamics. Flows were mapped using optical and infrared imagery, uncrewed aircraft systems, and airborne single-pass InSAR. Video- and time-lapse cameras were deployed to record lava fountaining and channelized flow at frequent intervals, supplemented by field measurements. Analyses of these data built a detailed record of effusion rates and associated flow dynamics. We combine these high frequency observations of the proximal flow field with broader thermal and 3-D mapping of the evolution in the medial and distal flow field to examine ʻaʻā flow dynamics from source to toe. Within the steep, medial section of the flow field, channel blockages caused back-ups and overflows as the eruption progressed. Disrupted lava supply to the distal flow field and low slopes resulted in stalling, widening, and thickening at the toe. Overall, 142 million m3 of lava covered 36 km2 over 13 days. Our results inform the controls on development and evolution of lava flow fields, with implications for forecasting primary flow advance and secondary flow field growth.

Hawaii↗
USGS2026

Discrete element investigation of the influence of shallow soil density on the manifestations of strike-slip surface fault rupture

This study investigates the influence of soil relative density on strike-slip surface fault rupture manifestations using three-dimensional numerical simulations performed with the discrete element method (DEM). The simulations capture the formation of distinctive fault strands within complex flower structures using tens of millions of grains. The tendency for dense soils to localize shear manifests as multiple localized shear bands within wide zones of deformation in strike-slip fault rupture, whereas diffuse shear deformation develops within narrow zones in loose soils. The spatial extents of soil deformation are consistent between simulations having similar relative densities but with different quantities of grains. However, individual shears are more distinguishable in assemblages of finer grains than in assemblages of coarser grains. The simulations show the progressive development of new shears within the bounds of previously developed shears. Shear activity transitions inward as fault activity diminishes along the outermost shears and continues along newly developed shears until a vertically dipping throughgoing shear structure develops that accommodates most of the fault displacement thereon. The throughgoing fault develops at smaller fault displacements in looser soils because the first shear rupture propagates closer to the vertical direction and does not undergo as much inward translation of shear activity, as is observed in denser soils. In all simulations, ground surface uplift develops between nonintersecting active shears, and ground surface subsidence tends to develop where new shears intersect previous shears. The surface traces in these simulations are shown to be consistent with analog models and case histories of surface fault rupture occurring in different shallow subsurface materials. Although computationally costly, these modeling results are valuable for providing a strong numerical supplement to traditional analog models used to represent the mechanics of strike-slip zones in soil, and they provide quantifiable stresses and large-strain deformations throughout the model domain.

Journal of Geotechnical and Geoenvironmental Engin↗
USGS2026

Using organic compounds and salt mixtures to investigate potential mechanisms of major ion toxicity to the mayfly Neocloeon triangulifer

Field assessments and laboratory studies have demonstrated that mayflies (Ephemeroptera) are relatively sensitive to increased concentrations of major geochemical ions (Na + , Ca 2+ , Mg 2+ , K + , Cl − , SO 4 2− , HCO 3 − /CO 3 2- ), but much remains to be learned about potential mechanisms of toxicity. In the present study, we sought to determine whether solution osmolarity is sufficient to predict the toxic effects of major ions to a mayfly, Neocloeon triangulifer . We further investigated whether binary mixtures of major ion salts with common cations or common anions provide evidence of concentration addition or independent action, potentially illuminating toxicity drivers for this species. Finally, we sought to determine if there are mechanisms for major ion toxicity to mayflies that are comparable to those for other species. The toxicity of single salts showed a Ca-dependent correlation with the total component concentration (the sum of individual ion concentrations, a close correlate of osmolarity), but the effect concentrations were well below those causing toxicity from mannitol (presumed to have only an osmotic effect), suggesting that a general osmotic effect is not responsible for major ion toxicity in this species. The mixture experiments consistently indicated additive toxicity and consistency with the relationship to total component concentration, which supports a single toxic mechanism and thus no evidence for ion-specific mechanisms, as reported for other species. Given the lack of evidence of ion-specific toxicity, the total component metric is likely useful for a broad range of ionic compositions.

Environmental Toxicology and Chemistry↗
USGS2026

Monitoring reservoir processes at The Geysers geothermal field: Joint time-lapse acquisition and cooperative joint inversion of passive seismic and magnetotelluric data

To monitor time-lapse changes in reservoir water and steam concentrations, as well as subsurface flow in the geysers geothermal field in California, we implemented a multi-physics geophysical imaging approach. This approach utilized continuously monitored microseismic events coupled with repeat magnetotelluric (MT) observations. Travel time data from microseismic events recorded at surface stations were collected over an area of approximately 75 km² continuously from 2018 to 2023, alongside three repeat MT surveys conducted in 2021, 2022, and 2023. The resulting seismic and MT data were inverted both separately and jointly to generate time-lapse images of geophysical properties that correspond to temporal changes in water and steam saturation within the reservoir, as well as flow paths and barriers. By correlating the geophysical images with known water injection and steam production volumes, we were able to calibrate the data and gain confidence in the results, which can now be applied throughout the reservoir where borehole data are unavailable. The joint imaging results, combined with reservoir data derived from borehole observations, allow for the interpretation of temporal changes in the reservoir. This enables the operator to optimize reservoir management and their drilling program.

California↗
USGS2026

Bank-dwelling beavers contribute to the wood regime in a dryland river

Our findings suggest that the influence of dwelling beavers on large wood budgets may substantially determine the structure and function of medium to large rivers, particularly in dryland systems such as the White River. Recognizing the role of bank-dwelling beavers expands our understanding of biotic drivers of riverscape complexity and provides new opportunities to integrate ecology with fluvial geomorphology in managing and restoring dynamic river corridors.

Utah↗
USGS2026

Syn-emplacement crystallization of Mauna Loa 2022 lava flows, Hawaiʻi

Advances in near-real-time forecasts of lava flow advance rates, final travel distance, and areal coverage are transforming hazard response, particularly in locations such as Hawaiʻi that experience frequent lava flow activity. The most severe threats are posed by rapidly advancing channelized ʻaʻā flows, such as those that characterized the November–December 2022 eruption of Mauna Loa volcano. To constrain rheological inputs to flow forecasting models during the eruption, samples were collected from the two most persistent lava flows and rapidly assessed for downflow changes in crystallinity and vesicularity. As observed in other channelized lava flows, the lava lost bubbles and cooled during transport, with consequent increases in groundmass crystallinity and bulk viscosity. Lava rheology, however, is controlled by more than bulk bubble and crystal contents; also important are the melt viscosity and the size and shape distributions of bubbles and crystals. Here we further interrogate the sample suite to document a down flow increase of almost two orders of magnitude in melt viscosity alone (a function of cooling combined with compositional change) and assess the extreme anisotropy of the plagioclase crystals as a function of size and flow type (pāhoehoe or ʻaʻā). When combined with previous studies, these data constrain observed relations between surface morphology, flow temperature and crystal content and indicate that remote assessments of morphological transitions and core lava temperature could be used for channel-wide monitoring of rheological evolution for assimilation into flow models.

Hawaii↗
USGS2026

A 40,000-year packrat midden series from Cataviña, central Baja California, Mexico

Thirty packrat ( Neotoma spp.) middens collected from boulder fields near Cataviña, Baja California, Mexico, at 640–680 m elevation provide the first long chronology of macrofossils and pollen spanning the late Quaternary in the Central Desert of Baja California. Midden plant macrofossil and pollen assemblages document a rich chaparral/woodland assemblage during the last glacial and early Holocene dominated by Parry pinyon ( Pinus quadrifolia ) and California juniper ( Juniperus californica ) until 11,630 cal yr BP. This indicates chaparral/woodland had a much more extensive distribution in what are now desert elevations in northern and central Baja California. In contrast to late glacial and early Holocene midden records from northeastern Baja, the Cataviña middens of the same age lack plants adapted to warm season precipitation, suggesting that decreased temperatures and evapotranspiration during the growing season and enhanced winter precipitation, with little contribution from summer rains, supported the lowering of chaparral/woodland species distributions in central Baja California. Cataviña middens also record endemic desert plant taxa mixed in with chaparral/woodland species during the Pleistocene, persisting throughout the Holocene, followed by the quick arrival of other desert species after ∼11,000 cal yr BP. Baja California remains a high-potential yet poorly sampled area for packrat midden research in North America.

Baja California↗
USGS2026

Landscape connectivity and wildlife access to water across an international border: Barriers and opportunities for facilitating transboundary movement

Rapid global acceleration in the construction of physical barriers along international borders has greatly influenced biodiversity and animal movement. Physical barriers can fragment landscapes, hinder access to essential resources, impact long-distance migrations, and inhibit dispersal and gene flow. The effects of physical barriers on animal movement and landscape connectivity can be exacerbated in dryland environments where access to water is a limiting factor. In recent decades, the construction of border barrier infrastructure has accelerated along the international boundary between the United States and Mexico. Here, we used a landscape connectivity model to investigate the effects of barriers on wildlife access to the river in the Lower Rio Grande Valley. We used a modified omnidirectional connectivity model to compare access to the river for three large, terrestrial mammal species across three border barrier scenarios: (1) a landscape without border barriers; (2) a landscape with the existing barrier system; and (3) a potential future landscape with a continuous barrier system. The existing barrier system includes many discrete sections of barrier within tracts of the Lower Rio Grande Valley National Wildlife Refuge or on lands associated with the region's flood control system. Our results indicate that the existing border barriers can impede connectivity and wildlife access to the river in some areas, while some existing gaps between border barrier sections can serve as conduits for wildlife movement and river access. Our future scenario results show how a potential continuous border barrier system could further impede wildlife access to the river. We discuss management and landscape conservation options for enhancing wildlife access to water and riverine habitats. Collectively, our results illustrate the potential effects of border barriers on wildlife movement and access to water, providing information that can be used to better anticipate and lessen the ecological impacts of transboundary barriers.

Tamaulipas, Texas↗
USGS2026

Can surface treatments and climate matching enhance restoration success in the Sonoran Desert?

Introduction Restoring native plant communities in arid ecosystems through seeding is a critical yet often unsuccessful strategy due to severe environmental stressors, including degraded soils, low and variable rainfall, and seed predation. Objectives To improve restoration outcomes, we examined the influence of seed mix types and soil surface treatments on seeded and unseeded plant establishment across three Sonoran Desert sites, Arizona, United States. Methods Using a factorial design, we tested two seed mix types (cool versus warm adapted species) and four soil surface treatments (pits, mulch, connectivity modifiers or ConMods, and controls) on plant establishment. We examined if patterns of plant establishment could be predicted by whether the climate envelope of species in the seed mix types was similar to the site climate where they were seeded (climate matching). We monitored seeded and unseeded species establishment for 3 years and analyzed these effects using generalized linear mixed models and Tukey-adjusted multiple comparisons. Results Pit treatments significantly enhanced seeded species density by nearly 3× and cover by 2× compared with ConMods and increased unseeded plant density by 2× to 4× times during post-drought springs. During these same seasons, species suited to cooler temperatures (e.g. Salvia columbariae and Lupinus sparsiflorus ) had higher cover at the site receiving the highest precipitation, and species suited to warmer temperatures (e.g. Sphaeralcea ambigua and Senna covesii ) established better at the drier two sites. Conclusions In arid systems, surface treatments like pits that retain soil moisture were most promising for supporting seed-based restoration, and matching species that have high temperature tolerance with hotter, drier sites may enhance restoration success.

Arizona↗