Legacies of Indigenous land use shaped past wildfire regimes in the Basin-Plateau Region, USA

AbstractClimatic conditions exert an important influence on wildfire activity in the western United States; however, Indigenous farming activity may have also shaped the local fire regimes for millennia. The Fish Lake Plateau is located on the Great Basin–Colorado Plateau boundary, the only region in western North America where maize farming was adopted then suddenly abandoned. Here we integrate sedimentary archives, tree rings, and archeological data to reconstruct the past 1200 years of fire, climate, and human activity. We identify a period of high fire activity during the apex of prehistoric farming between 900 and 1400 CE, and suggest that farming likely obscured the role of climate on the fire regime through the use of frequent low-severity burning. Climatic conditions again became the dominant driver of wildfire when prehistoric populations abandoned farming around 1400 CE. We conclude that Indigenous populations shaped high-elevation mixed-conifer fire regimes on the Fish Lake Plateau through land-use practices.

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The Role of Transhumance on Land Use /Cover Changes in Mountain Vermio, Northern Greece: A GIS Based Approach

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha45210933 ◽

2017 ◽

Vol 45 (2) ◽

pp. 589-596 ◽

Cited By ~ 2

Author(s):

Paraskevi SKLAVOU ◽

Maria KARATASSIOU ◽

Zoi PARISSI ◽

Georgia GALIDAKI ◽

Athanasios RAGKOS ◽

...

Keyword(s):

Land Use ◽

Geographical Information Systems ◽

Geographical Area ◽

Spatial Differentiation ◽

High Elevation ◽

Climatic Conditions ◽

Geographical Information ◽

Northern Greece ◽

Open Forests

Transhumant flocks graze the vegetation of medium and high elevation rangelands during late spring to autumn depending on the geographical area and climatic conditions. This study aimed to assess and interpret the impacts of transhumance decline on the land use/cover on Mountain Vermio, for the period 1985-2009. For many years, this area has received high stocking rates from transhumant livestock. However, during the last 30 years transhumance has been dramatically decreased. Land cover changes have been identified using a post classification comparison approach within a Geographical Information Systems environment. Moreover, the rate and the spatial differentiation of land use/cover were determined by means of the Dynamic Degree Index. According to the results, the acreage of grasslands and grazed open forests has decreased during the study period (3% and 83% respectively), while shrublands demonstrated an opposite trend with an increase of 25%. Furthermore, based on the Dynamic Degree Index, the greatest changes occurred in the conversion of grazed open forests and shrublands, compared to other land use/cover categories. This can be attributed to changes in sheep and goats populations grazing in the area, also related to the dispersion of flocks in local rangelands. Moreover, this article presents the results of a questionnaire survey on transhumant herders. These results, combined with the assessment of changes in the Dynamic Degree Index, reflect the difficulties that farmers face in terms of access to rangelands and their increased awareness regarding the environmental role of transhumance.

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Fire regime shift linked to increased forest density in a piñon–juniper savanna landscape

International Journal of Wildland Fire ◽

10.1071/wf13053 ◽

2014 ◽

Vol 23 (2) ◽

pp. 234 ◽

Cited By ~ 17

Author(s):

Ellis Q. Margolis

Keyword(s):

Regime Shift ◽

Fire History ◽

Fire Regime ◽

Fire Regimes ◽

Fire Frequency ◽

Climatic Conditions ◽

Tree Density ◽

High Severity ◽

Wide Range ◽

In Fire

Piñon–juniper (PJ) fire regimes are generally characterised as infrequent high-severity. However, PJ ecosystems vary across a large geographic and bio-climatic range and little is known about one of the principal PJ functional types, PJ savannas. It is logical that (1) grass in PJ savannas could support frequent, low-severity fire and (2) exclusion of frequent fire could explain increased tree density in PJ savannas. To assess these hypotheses I used dendroecological methods to reconstruct fire history and forest structure in a PJ-dominated savanna. Evidence of high-severity fire was not observed. From 112 fire-scarred trees I reconstructed 87 fire years (1547–1899). Mean fire interval was 7.8 years for fires recorded at ≥2 sites. Tree establishment was negatively correlated with fire frequency (r=–0.74) and peak PJ establishment was synchronous with dry (unfavourable) conditions and a regime shift (decline) in fire frequency in the late 1800s. The collapse of the grass-fuelled, frequent, surface fire regime in this PJ savanna was likely the primary driver of current high tree density (mean=881treesha–1) that is >600% of the historical estimate. Variability in bio-climatic conditions likely drive variability in fire regimes across the wide range of PJ ecosystems.

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The origins of prescribed burning in Scandinavian forestry: the seminal role of Joel Wretlind in the management of fire-dependent forests

European Journal of Forest Research ◽

10.1007/s10342-019-01247-6 ◽

2019 ◽

Vol 139 (3) ◽

pp. 393-406

Author(s):

Sarah Cogos ◽

Samuel Roturier ◽

Lars Östlund

Keyword(s):

Prescribed Fire ◽

Prescribed Burning ◽

Fire Regime ◽

Fire Suppression ◽

Fire Regimes ◽

The State ◽

Natural Processes ◽

Forest Manager ◽

Forest District

AbstractIn Sweden, prescribed burning was trialed as early as the 1890s for forest regeneration purposes. However, the origins of prescribed burning in Sweden are commonly attributed to Joel Efraim Wretlind, forest manager in the State Forest district of Malå, Västerbotten County, from 1920 to 1952. To more fully understand the role he played in the development of prescribed burning and the extent of his burning, we examined historical records from the State Forest Company’s archive and Wretlind’s personal archive. The data showed that at least 11,208 ha was burned through prescribed burning between 1921 and 1970, representing 18.7% of the Malå state-owned forest area. Wretlind thus created a new forestry-driven fire regime, reaching, during peak years, extents close to historical fire regimes before the fire suppression era, and much higher than present-day burning. His use of prescribed fire to regenerate forests served as a guide for many other forest managers, spreading to all of northern Sweden during the 1950–1960s. Our analysis of Wretlind’s latest accounts also shows how he stood against the evolutions of modern forestry to defend a forestry system based on the reproduction of natural processes, such as fire.

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Fire history in Andean Araucaria–Nothofagus forests: coupled influences of past human land-use and climate on fire regimes in north-west Patagonia

International Journal of Wildland Fire ◽

10.1071/wf19174 ◽

2020 ◽

Vol 29 (8) ◽

pp. 649 ◽

Cited By ~ 1

Author(s):

Mauro E. González ◽

Ariel A. Muñoz ◽

Álvaro González-Reyes ◽

Duncan A. Christie ◽

Jason Sibold

Keyword(s):

Climate Change ◽

Land Use ◽

Fire History ◽

Fire Regime ◽

Fire Regimes ◽

Forest Landscape ◽

Araucaria Forest ◽

North West ◽

Human Land Use ◽

Nothofagus Forests

Historical fire regimes are critical for understanding the potential effects of changing climate and human land-use on forest landscapes. Fire is a major disturbance process affecting the Andean Araucaria forest landscape in north-west Patagonia. The main goals of this study were to reconstruct the fire history of the Andean Araucaria–Nothofagus forests and to evaluate the coupled influences of climate and humans on fire regimes. Reconstructions of past fires indicated that the Araucaria forest landscape has been shaped by widespread, stand-replacing fires favoured by regional interannual climate variability related to major tropical and extratropical climate drivers in the southern hemisphere. Summer precipitation and streamflow reconstructions tended to be below average during fire years. Fire events were significantly related to positive phases of the Southern Annular Mode and to warm and dry summers following El Niño events. Although Euro-Chilean settlement (1883–1960) resulted in widespread burning, cattle ranching by Pehuenche Native Americans during the 18th and 19th centuries also appears to have changed the fire regime. In the context of climate change, two recent widespread wildfires (2002 and 2015) affecting Araucaria forests appear to be novel and an early indication of a climate change driven shift in fire regimes in north-west Patagonia.

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Fire regimes of the piñon–juniper woodlands of Big Bend National Park and the Davis Mountains, west Texas, USA

Canadian Journal of Forest Research ◽

10.1139/x09-052 ◽

2009 ◽

Vol 39 (6) ◽

pp. 1236-1246 ◽

Cited By ~ 16

Author(s):

H.M. Poulos ◽

R.G. Gatewood ◽

A.E. Camp

Keyword(s):

National Park ◽

Fire Regime ◽

Fire Regimes ◽

Climatic Conditions ◽

Tree Regeneration ◽

Big Bend National Park ◽

Fire Scar ◽

West Texas ◽

Big Bend ◽

Davis Mountains

While piñon woodlands cover much of arid North America, surprisingly little is known about the role of fire in maintaining piñon forest structure and species composition. The lack of region-specific fire regime data for piñon–juniper woodlands presents a roadblock to managers striving to implement process-based management. This study characterized piñon–juniper fire regimes and forest stand dynamics in Big Bend National Park (BIBE) and the Davis Mountains Preserve of the Nature Conservancy (DMTNC) in west Texas. Mean fire return intervals were 36.5 and 11.2 years for BIBE and DMTNC, respectively. Point fire return intervals were 150 years at BIBE and 75 years at DMTNC. Tree regeneration in west Texas piñon–juniper woodlands occurred historically during favorable climatic conditions following fire years. The presence of multiple fire scars on our fire-scar samples and the multicohort stands of piñon suggested that low intensity fires were common. This study represents one of the few fire-scar-based fire regime studies for piñon–juniper woodlands. Our results differ from other studies in less topographically dissected landscapes that have identified stand-replacing fire as the dominant fire regime for piñon–juniper woodlands. This suggests that mixed-severity fire regimes are typical across southwestern piñon forests, and that topography is an important influence on fire frequency and intensity.

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The contradictory role of fire from the nature conservation perspective

10.5194/egusphere-egu2020-10518 ◽

2020 ◽

Author(s):

Orsolya Valkó

Keyword(s):

Nature Conservation ◽

Land Surface ◽

Fire History ◽

Prescribed Burning ◽

Fire Regime ◽

Fire Regimes ◽

Fire Effects ◽

Negative Effects ◽

Fire Policy

Fire is a globally relevant natural or anthropogenic phenomenon with a rapidly increasing importance in the era of the climate change. In each year, approximately 4% of the global land surface burns. For effective ecosystem conservation, we need to understand fire regimes, identify potential threats, and also the possibilities in the application of prescribed burning for maintaining ecosystems.Here I provide an overview on the contradictory role of fire in nature conservation from two continents with contrasting fire histories, focusing on European and North-American grasslands. I show that the ecological effects of fire depend on the fire regime, fire history, ecosystem properties and the socio-economic environment. Catastrophic wildfires, arson, too frequent or improperly planned human-induced fire often lead to the degradation of the ecosystems, the disappearance of rare plant and animal species, and to the encroachment of weed and invasive species. I illustrate with examples that these negative fire effects act synergistically with the human-induced changes in land use systems.I also underline with case studies that in both regions, properly designed and controlled prescribed burning regimes can aid the understanding and managing disturbance-dependent ecosystems. Conservation in these dynamic and complex ecosystems is far more than fencing and hoping to exclude disturbance; but the contrary: disturbance is needed for ecosystem functioning. Therefore, the conservation of dynamic, diverse and functioning ecosystems often require drastic interventions and an unconventional conservation attitude. However, the expanding urban-wildlife interface makes the application of prescribed burning challenging worldwide. A major message for the future is about fire policy: it is crucial to moderate the negative effects of fire, however, properly designed prescribed burning should be used as a tool for managing and conserving disturbance-dependent ecosystems.

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Climatic and anthropogenic factors affect Ailanthus altissima invasion in a Mediterranean region

Plant Ecology ◽

10.1007/s11258-021-01183-9 ◽

2021 ◽

Author(s):

Riccardo Motti ◽

Maurizio Zotti ◽

Giuliano Bonanomi ◽

Alessia Cozzolino ◽

Adriano Stinca ◽

...

Keyword(s):

Land Use ◽

Propagule Pressure ◽

Ecological Factors ◽

Mediterranean Ecosystems ◽

High Elevation ◽

Climatic Conditions ◽

Anthropogenic Factors ◽

Ailanthus Altissima ◽

Poor Correlation ◽

Mean Annual Temperature

AbstractAilanthus altissima is an aggressive invasive tree worldwide, but the ecological factors that lead to the spread of this species in Mediterranean ecosystems are still unclear. Here we aim to identify such factors, focusing on the interaction of human activity with climatic conditions. We determined the occurrence and abundance of Ailanthus in 240 sites and studied their relationship with 20 variables representing climatic, geographic, and topographic factors, as well as land use, in the region of Campania (southern Italy). Overall, we found that temperature and rainfall in Campania are suitable for Ailanthus, with the only major constraint being the temperature at an altitude exceeding 900 m a.s.l.. We found that Ailanthus is unable to spread where the mean annual temperature is lower than 11.1 °C. By contrast, precipitation variables showed poor correlation with Ailanthus distribution, suggesting that rainfall in the selected study sites is suitable to sustain the growth of this tree. About land use variables, roads were the primary landscape feature along which this species spread and invaded new areas. Roads probably combine high propagule pressure and favorable growing conditions in terms of available resources i.e., light, water, and mineral nutrients, that allow Ailanthus to establish and spread along roadside edges in different ecosystems. In conclusion, we found that climate and human-associated variables are correlated with the current occurrence of Ailanthus, with the temperature being more influential at high elevation sites and road distance playing a prominent role in low elevation areas.

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Influence of climate and environment on post-fire recovery of mountain big sagebrush

International Journal of Wildland Fire ◽

10.1071/wf13012 ◽

2014 ◽

Vol 23 (1) ◽

pp. 131 ◽

Cited By ~ 36

Author(s):

Zachary J. Nelson ◽

Peter J. Weisberg ◽

Stanley G. Kitchen

Keyword(s):

Great Basin ◽

Recovery Rate ◽

Fire Regime ◽

Seedling Survival ◽

High Elevation ◽

Deep Soil ◽

Big Sagebrush ◽

Survival Percentage ◽

Water Recharge ◽

Recovery Times

In arid and semi-arid landscapes around the world, wildfire plays a key role in maintaining species diversity. Dominant plant associations may depend upon particular fire regime characteristics for their persistence. Mountain shrub communities in high-elevation landscapes of the Intermountain West, USA, are strongly influenced by the post-fire recovery dynamics of the obligate-seeding shrub, mountain big sagebrush (Artemisia tridentata Nutt. ssp. vaseyana [Rydb.] Beetle). This species is a short-distance disperser with a short-lived seedbank, leading to highly variable post-fire recovery times (15–100 years). We investigated the relative importance of site productivity and seasonal climate in explaining the variance in recovery time for 36 fires, comprising a fire chrono-sequence (from 1971 to 2007) for the Great Basin and Colorado Plateau. A. t. vaseyana recovery was positively related to precipitation in the cool season immediately following fire, likely because deep soil-water recharge that persists throughout the growing season enhances first-year seedling survival. Percentage sand fraction positively correlated with recovery rate yet negatively correlated with live cover in unburnt stands. Our data support the hypothesis that post-fire recovery rate of A. t. vaseyana depends on the climatically controlled ephemerality of the regeneration niche, as is likely true for many arid-land shrub species.

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The Eneolithic/Bronze Age Transition at Tegole di Bovino (Apulia): Geoarchaeological Evidence of Climate Change and Land-Use Shift

Quaternary ◽

10.3390/quat3020014 ◽

2020 ◽

Vol 3 (2) ◽

pp. 14

Author(s):

Guido S. Mariani ◽

Italo M. Muntoni ◽

Andrea Zerboni

Keyword(s):

Land Use ◽

Bronze Age ◽

Southern Italy ◽

Archaeological Site ◽

Climatic Conditions ◽

Human Occupation ◽

Climatic Fluctuations ◽

Sedimentary Deposits ◽

The Bronze Age

Human communities at the transition between the Eneolithic period and the Bronze Age had to rapidly adapt to cultural and climatic changes, which influenced the whole Mediterranean. The exact dynamics involved in this crucial passage are still a matter of discussion. As newer studies have highlighted the key role of climatic fluctuations during this period, their relationship with the human occupation of the landscape are yet to be fully explored. We investigated the infilling of negative structures at the archaeological site of Tegole di Bovino (Apulia, Southern Italy) looking at evidence of the interaction between climate changes and human strategies. The archaeological sedimentary deposits, investigated though geoarchaeological and micromorphological techniques, show the presence of natural and anthropogenic infillings inside most structures. Both human intervention and/or natural events occurred in the last phases of occupation of the site and its subsequent abandonment. The transition to unfavorable climatic conditions in the same period was most likely involved in the abandonment of the site. The possible further impact of human communities on the landscape in that period, testified by multiple other archives, might have in turn had a role in the eventual change in land use.

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Future fires in the Coupled Model Intercomparison Project (CMIP) phase 6

10.5194/egusphere-egu2020-22513 ◽

2020 ◽

Author(s):

Gitta Lasslop ◽

Stijn Hantson ◽

Victor Brovkin ◽

Fang Li ◽

David Lawrence ◽

...

Keyword(s):

Land Use ◽

Fire Regime ◽

Coupled Model ◽

Fire Regimes ◽

Atmospheric Composition ◽

Cloud Formation ◽

Burned Area ◽

Earth System ◽

System Models ◽

Earth System Models

Fires are an important component in Earth system models (ESMs), they impact vegetation carbon storage, vegetation distribution, atmospheric composition and cloud formation. The representation of fires in ESMs contributing to CMIP phase 5 was still very simplified. Several Earth system models updated their representation of fires in the meantime. Using the latest simulations of CMIP6 we investigate how fire regimes change in the future for different scenarios and how land use, climate and atmospheric CO2 concentration contribute to the fire regimes changes. We quantify changes in fire danger, burned area and carbon emissions on an annual and seasonal basis. Factorial model simulations allow to quantify the influence of land use, climate and atmospheric CO2 on fire regimes.We complement the information on fire regime change supplied by ESMs that include a fire module with a statistical modelling approach for burned area. This will use information from simulated changes in climate, vegetation and socioeconomic changes (population density and land use) provided for a set of different future scenarios. This allows the integration of information provided by global satellite products on burned area with the process-based simulations of climate and vegetation changes and information from socioeconomic scenarios.&#160;

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