Fire-driven animal evolution in the Pyrocene

Trends in Ecology & Evolution, Journal Year: 2023, Volume and Issue: 38(11), P. 1072 - 1084

Published: July 19, 2023

Language: Английский

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Post‐Wildfire Stability of Unsaturated Hillslopes Against Rainfall‐Triggered Landslides

Earth s Future, Journal Year: 2023, Volume and Issue: 11(3)

Published: March 1, 2023

Abstract Wildfire records demonstrate worsening patterns coupled with the spread to higher altitudes in several regions, raising risk of post‐wildfire ground failures. This study investigates stability unsaturated hillslopes against rainfall‐triggered shallow landslides. We developed a new physics‐based analytical framework incorporating wildfire‐induced changes soil properties and near‐surface processes affecting hillslope stability. A hydromechanical infiltration model is integrated into an infinite slope analysis simulate temporal depth profiles water content, pressure head, resulting factor safety (F.S.) vegetated slope. consider antecedent conditions vegetation cover, including recovery phase after fire, alterations transpiration, time‐varying rates. The verified numerical simulations employed parametric studies evaluating effects wildfire severity rainfall intensity‐duration. For cases examined, it was shown that could reduce F.S. slopes by 25%. As case study, successfully captured landslides occurred Las Lomas watershed California, USA, 2019, 3 years Fish Fire burned area. proposed uses measurable characteristics can be evaluate wildfire‐prone areas.

Language: Английский

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Impacts of beaver dams on riverscape burn severity during megafires in the Rocky Mountain region, western United States

Geological Society of America eBooks, Journal Year: 2024, Volume and Issue: unknown, P. 131 - 151

Published: Jan. 15, 2024

ABSTRACT Megafires, defined as fires with burn areas greater than 100,000 acres (404.7 km2), result partly from increasingly short wet seasons coupled consistently hotter, drier summers, and past forest management decisions. Historically rare, megafires have become common in recent years. In this study, we examined the impact of on riverscapes beaver dams to explore resilience these habitats. We investigated whether beaver-modified are more resistant impacts geomorphically similar lacking dams. Our analysis utilized remotely sensed field-collected data three Rocky Mountain region that burned 2020. results showed riparian (1537 dams, which occurred 658 out 13,933 valley bottom segments evaluated) had significantly reduced severity compared without or outside river corridor. Additionally, when were classified according their modeled dam capacities (a metric closely linked habitat quality), lower intensities those even within same theoretical capacity class. indicate a high degree manipulation by beavers significant resistance burning during megafires. This may also provide valuable secondary benefits postfire ecosystem health, water quality, biodiversity.

Language: Английский

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Short-Term Effects and Vegetation Response after a Megafire in a Mediterranean Area

Land, Journal Year: 2022, Volume and Issue: 11(12), P. 2328 - 2328

Published: Dec. 19, 2022

In Mediterranean-climate areas, wildfires have an important ecological role, selecting organisms, influencing species composition and structure of vegetation, shaping landscapes. However, the increase in frequency severity fires can cause, among others, progressive vegetation degradation, biodiversity, ecosystem services loss. Under climate change scenario, are expected to increase, especially Mediterranean Basin, recognized as most affected by intensification droughts heat waves future. Therefore, from perspective adaptation, it is not only assess sudden effects after a fire but also investigate changes response over time. this framework, study investigates short-term area struck megafire. The one year has been assessed semi-natural grasslands, shrublands, woodlands at landscape scale through spectral indices, field floristic surveys. Our results showed that severe wildfire, although some areas did exhibit regrowth, natural was notable year. area, resilient type suggesting be crucial for recovery. other types different patterns prefigure possible loss plant diversity medium term. This highlights value combining remote sensing analyses detailed surveys understanding direction early stages post-fire dynamics.

Language: Английский

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Shifting season of fire and its interaction with fire severity: Impacts on reproductive effort in resprouting plants

Ecology and Evolution, Journal Year: 2022, Volume and Issue: 12(3)

Published: March 1, 2022

Fire regimes shape plant communities but are shifting with changing climate. More frequent fires of increasing intensity burning across a broader range seasons. Despite this, impacts that changes in fire season have on populations, or how they interact other regime elements, still relatively understudied. We asked (a) does the affect vigor, including vegetative growth and flowering after event, (b) do different functional resprouting groups respond differently to effects fire? sampled total 887 plants 36 sites using space-for-time design assess vigor reproductive output for five species. Sites represented either spring autumn burn, aged one three years old. Season had clearest Lambertia formosa 152% increase number 45% flowers per compared fires. There were also × severity interactions produced

Language: Английский

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Soil microbial community composition and functions are disrupted by fire and land use in a Mediterranean woodland

The Science of The Total Environment, Journal Year: 2023, Volume and Issue: 895, P. 165088 - 165088

Published: June 24, 2023

The intersection of fire, land use transformations, and climate change is putting Mediterranean climate-type ecosystems at risk soil degradation loss ecosystem services. Ondik et al. (2022b) showed that in a dry sclerophyll woodland South Australia, high severity fire clearing grazing practices impacted both physicochemical biological quality indicators. Building upon the work this study aims to 1) identify properties by management are indirect drivers changes microbial community composition 2) determine whether observed affect functions. Via redundancy analysis, we identified management-induced pH, water repellency, nutrient stoichiometry, total content as significant communities. We then measured basal respiration, substrate induced carbon mineralisation quotient, calculated functional trait distributions among communities linking 16S 18S rRNA sequences respiration modes guilds, respectively. found reduced relative abundance (RA) symbionts, anaerobic bacteria, microaerophilic while increasing RA aerobic bacteria. Furthermore, increased post-fire ectomycorrhizal fungi may have pathogenic load, efficiency, wood saprotrophs, litter, soil, other saprotrophic species adapted grasslands. This shows that, through composition, wildfire affected rates, bacterial prevalence symbiotic bacteria fungi, preference. Having main provide valuable insights into how can impact soils woodland.

Language: Английский

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Short-interval, high-severity wildfires cause declines in soil seed bank diversity in montane forests of south-eastern Australia

Forest Ecology and Management, Journal Year: 2023, Volume and Issue: 553, P. 121627 - 121627

Published: Dec. 8, 2023

Wildfires in forested ecosystems are increasing severity and extent. The adaptations many plants have acquired response to their natural fire regime may not be sufficient allow some species persist. This could impact the forest understorey its seed bank, which vital reservoirs of biodiversity, resilience face global change. We present a case study montane forests south-eastern Australia, an area subjected increase frequency fires. utilise field surveys soil bank germination investigate if short-interval, high-severity wildfires affect diversity forests, extant vegetation exhibit contrasting responses. consider plant functional traits explore long unburned sites, sites with one, two or three fires past 25 years. With frequency, we found decrease total richness, Shannon's diversity, richness resprouters lack vegetation. Increased shifted composition groups both towards clonal grasses other upright herbs. wind-dispersed perennials short-lived seeders exotics increased sharply following single high burn, particularly remained elevated relative unburnt subsequent fire. combined (extant plus bank) pool mirrored shifts bank. These findings highlight importance considering when examining effects on fire-prone forests. Although buffering effect shift suggests this cannot maintained indefinitely. abundance characteristic early successional states has implications for flammability potential positive feedbacks between future fire, especially warming drying climate. were independent strategy eucalypt canopy raising significant questions whether artificial re-seeding programs should extend beyond current focus obligate seeding tree.

Language: Английский

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Frequent burning and limited stand-replacing fire supports Mexican spotted owl pair occupancy

Fire Ecology, Journal Year: 2024, Volume and Issue: 20(1)

Published: April 21, 2024

Abstract Changing fire regimes have the potential to threaten wildlife populations and communities. Understanding species’ responses novel is critical formulating effective management conservation strategies in an era of rapid change. Here, we examined empirical effects recent historical wildfire activity on Mexican spotted owl ( Strix occidentalis lucida ) southwestern United States. Using region-wide, standardized detection/non-detection data breeding pairs collected from 2015 2022, found i higher rates pair occupancy at sites that experienced more frequent fires three decades prior initiation our study, ii lower local persistence extensive high-severity during study. Historical throughout much study area were characterized by high frequencies limited components, indicating owls responded a manner consistent with their evolutionary environment. Management activities such as prescribed burning mechanical thinning aim reduce stand-replacing risk re-introduce for frequent-fire will likely benefit objectives, well promote resilient forest landscapes.

Language: Английский

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Using Patterns of Post‐Fire Plant Reproduction to Inform Minimum Fire Intervals for Conservation Management in a Fire‐Prone Woodland

Austral Ecology, Journal Year: 2025, Volume and Issue: 50(1)

Published: Jan. 1, 2025

ABSTRACT The time interval between fires is a critical component of the fire regime that affects plant species persistence in fire‐prone ecosystems. Fire intervals are too short or long may not support regeneration from seed banks resprouting. adequate also vary with other factors such as climate, herbivory, and population structure. Using field data on flowering canopy banks, we modelled post‐fire reproduction for woody fire‐killed (obligate seeding) resprouting under varying rainfall herbivory along 35‐year age chronosequence Banksia woodlands southwestern Australia. We found attained reproductive maturity rapidly after predicted juvenile periods (time to 50% flowering) 1.5–2.3 years shrubs 4 trees. Resprouting had similar (1–3.5 shrubs, 4.4 trees). Reproduction varied at least doubling low high some species. Serotinous produced cones (woody fruits containing seeds) shortly commenced, evidence bank decline oldest sites. While was clearly correlated since fire, size much stronger predictor. Some form multi‐cohort populations which can introduce large variation into trajectories, this should be considered when making decisions about impact persistence. This study provides information assess interval‐related threats suggests these generally tolerant wide range intervals. Only slowest‐maturing, ( prionotes , Proteaceae) require > 10 reduce immaturity risk favourable growing conditions, often occurs discrete patches landscape management tailored accordingly.

Language: Английский

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Defining the pyro‐thermal niche: do seed traits, ecosystem type and phylogeny influence thermal thresholds in seeds with physical dormancy?

New Phytologist, Journal Year: 2025, Volume and Issue: unknown

Published: March 14, 2025

Summary Seeds are a key pathway for plant population recovery following disturbance. To prevent germination during unsuitable conditions, most species produce dormant seeds. In fire‐prone regions, physical dormancy (PY) enables seeds to germinate after fire. The pyro‐thermal niche, incorporating temperature effects into seed and mortality, has not been characterised PY from environments. We aimed assess variation in thermal thresholds between with whether the niche is correlated mass, ecosystem type or phylogenetic relatedness. collected post heat‐shock data 58 Australian that applied species‐specific performance curves define three critical (DRT 50 , release temperature; T opt optimum LT lethal temperature), defining niche. Each was assigned mean weight type. constructed phylogeny account relatedness calculated signal ( h 2 ) DRT . found consistent inverted u‐shaped response curve across all examined. within Rhamnaceae exhibited higher than those Fabaceae. Seed mass influential explaining variation. analysis presented here provides framework direct comparisons other nonfire‐prone species, which heat may play role postfire dynamics.

Language: Английский

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