Christopher I. Roos

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Verified

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• PhD
• Professor (Full) at Southern Methodist University

Significance Debates about the magnitude, tempo, and ecological effects of Native American depopulation after 1492 CE constitute some of the most contentious issues in American Indian history. Was population decline rapid and catastrophic, with effects extensive enough to change even the earth’s atmosphere? Or was depopulation more moderate, with i...

Significance The relative importance of human activities and climate in shaping fire regimes is controversial. In North American grasslands, climate exerts strong top-down influences on fuels. For centuries before the introduction of the horse, Native American and First Nations hunters built and used landscape features on these grasslands to harves...

Significance As residential development continues into flammable landscapes, wildfires increasingly threaten homes, lives, and livelihoods in the so-called “wildland–urban interface,” or WUI. Although this problem seems distinctly modern, Native American communities have lived in WUI contexts for centuries. When carefully considered, the past offer...

Prior research suggests that Indigenous fire management buffers climate influences on wildfires, but it is unclear whether these benefits accrue across geographic scales. We use a network of 4824 fire-scarred trees in Southwest United States dry forests to analyze up to 400 years of fire-climate relationships at local, landscape, and regional scale...

Remote islands in the Pacific Ocean (Oceania) experienced dramatic environmental transformations after initial human settlement in the past 3,000 yr. Here, human causality of this environmental degradation has been unquestioned and viewed as evidence of the inherent destructive tendencies of human societies in both archaeological and popular discou...

Remote islands in the Pacific Ocean (Oceania) experienced dramatic environmental transformations after initial human settlement in the past 3,000 yr. Here, human causality of this environmental degradation has been unquestioned and viewed as evidence of the inherent destructive tendencies of human societies in both archaeological and popular discou...

The impact of Indigenous populations on historical fire regimes has been controversial and beset by mismatches in the geographic scale of paleofire reconstructions and the scale of land-use behaviors. It is often assumed that anthropogenic burning is linearly related to population density and not different cultural practices. Here we take an off-si...

Fire is an integral component of ecosystems globally and a tool that humans have harnessed for millennia. Altered fire regimes are a fundamental cause and consequence of global change, impacting people and the biophysical systems on which they depend. As part of the newly emerging Anthropocene, marked by human-caused climate change and radical chan...

Fire is an integral component of ecosystems globally and a tool that humans have harnessed for millennia. Altered fire regimes are a fundamental cause and consequence of global change, impacting people and the biophysical systems on which they depend. As part of the newly emerging Anthropocene, marked by human-caused climate change and radical chan...

Colonialism has disrupted Indigenous socioecological systems around the globe, including those supported by intentional landscape burning. Because most disruptions happened centuries ago, our understanding of Indigenous fire management is largely inferential and open to debate. Here, we investigate the ecological consequences of the loss of traditi...

Humans have influenced global fire activity for millennia and will continue to do so into the future. Given the long-term interaction between humans and fire, we propose a collaborative research agenda linking archaeology and fire science that emphasizes the socioecological histories and consequences of anthropogenic fire in the development of fire...

Megafires in dry conifer forests of the Southwest US are driving transitions to alternative vegetative states, including extensive shrubfields dominated by Gambel oak ( Quercus gambelii). Recent tree-ring research on oak shrubfields that predate the 20th century suggests that these are not a seral stage of conifer succession but are enduring stable...

Supplementary Information for: Roos, Christopher I., Thomas W. Swetnam, T.J. Ferguson, Matthew J. Liebmann, Rachel A. Loehman, John R. Welch, Ellis Q. Margolis, Christopher H. Guiterman, William C. Hockaday, Michael J. Aiuvalasit, Jenna Battillo, Joshua Farella, and Christopher A. Kiahtipes (2021). Native American Fire Management at an Ancient Wil...

Here, we show that the last century of fire suppression in the western U.S. has resulted in fire intensities that are unique over more than 900 years of record in ponderosa pine forests (Pinus ponderosa). Specifically, we use the heat-sensitive luminescence signal of archaeological ceramics and tree-ring fire histories to show that a recent fire du...

Paleofire studies frequently discount the impact of human activities in past fire regimes. Globally, we know that a common pattern of anthropogenic burning regimes is to burn many small patches at high frequency, thereby generating landscape heterogeneity. Is this type of anthropogenic pyrodiversity necessarily obscured in paleofire records because...

The historical and modern importance of crown fires in ponderosa pine and dry mixed-conifer forests of the south-west USA has been much debated. The microscopic reflectance of charcoal in polished blocks under oil shows promise as a semiquantitative proxy for fire severity using charcoal from post-fire landscapes. We measured the reflectance of 33...

Slash-and-burn cultivation (swidden) is an important and extensive strategy among agriculturalists in Oceania. The length of the fallow period, in which non-cultivated vegetation is allowed to regrow, is critical to the sustainability of this strategy in tropical environments. Long fallow periods permit greater soil recovery and higher yields over...

Living with fire is a challenge for human communities because they are influenced by socio-economic, political, ecological and climatic processes at various spatial and temporal scales. Over the course of 2 days, the authors discussed how communities could live with fire challenges at local, national and transnational scales. Exploiting our diverse...

Fire has been an important part of the Earth system for over 350 Myr. Humans evolved in this fiery world and are the only animals to have used and controlled fire. The interaction of mankind with fire is a complex one, with both positive and negative aspects. Humans have long used fire for heating, cooking, landscape management and agriculture, as...

Interannual climate variations have been important drivers of wildfire occurrence in ponderosa pine forests across western North America for at least 400 years, but at finer scales of mountain ranges and landscapes human land uses sometimes over-rode climate influences. We reconstruct and analyse effects of high human population densities in forest...

Humans use combustion for heating and cooking, managing lands, and, more recently, for fuelling the industrial economy. As a shift to fossil-fuel-based energy occurs, we expect that anthropogenic biomass burning in open landscapes will decline as it becomes less fundamental to energy acquisition and livelihoods. Using global data on both fossil fue...

Wildfire risk in temperate forests has become a nearly intractable problem that can be characterized as a socioecological "pathology": that is, a set of complex and problematic interactions among social and ecological systems across multiple spatial and temporal scales. Assessments of wildfire risk could benefit from recognizing and accounting for...

In our 2011 synthesis (Bowman et al., Journal of Biogeography, 2011, 38, 2223–2236), we argued for a holistic approach to human issues in fire science that we term 'pyrogeography'. Coughlan & Petty (Journal of Biogeography, 2013, 40, 1010–1012) critiqued our paper on the grounds that our 'pyric phase' model was built on outdated views of cultural d...

Fire history reconstructions from fire scars in tree rings have been valuable for assessing fire regime changes and their climatic controls. It has been asserted, however, that these two- to four-century long records from the western USA are unrepresentative of longer periods of the Holocene and are of limited use for understanding current or futur...

Humans and their ancestors are unique in being a fire-making species, but ‘natural’ (i.e. independent of humans) fires have an ancient, geological history on Earth. Natural fires have influenced biological evolution and global biogeochemical cycles, making fire integral to the functioning of some biomes. Globally, debate rages about the impact on e...

In the fire-prone coniferous ecosystems of the American Southwest where archaeological sites are abundant and the ecological legacies of ancient societies are incompletely understood, the " anthropogenic fire " hypothesis has been underappreciated. We use a multiproxy, stratigraph-ic approach to reconstruct variation in fire regimes over the period...

Fire is a worldwide phenomenon that appears in the geological record soon after the appearance of terrestrial plants. Fire influences global ecosystem patterns and processes, including vegetation distribution and structure, the carbon cycle, and climate. Although humans and fire have always coexisted, our capacity to manage fire remains imperfect a...