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

Abstract

Climatic 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.

The North American tree‐ring fire‐scar network

“…The key to disentangling the influence on fire regimes of humans from climate lies in the emerging methodologies that allow the analysis and interpretation of tree‐ring based fire histories in the context of other forms of knowledge and historical ecology data. Specifically, these include multiproxy approaches that incorporate different lines of evidence of human land use (e.g., palaeoecological and archeological data; Whitlock et al, 2010, Carter et al, 2021), multidisciplinary approaches that draw on expertise from, among others, anthropology and human geography, and collaborative methodologies that engage directly with Indigenous fire knowledge keepers and scholars (Lake et al, 2017; Roos et al, 2021). Recognizing the nuanced contributions of people to fire regimes across North America will rely on future research that is place‐based, scale‐appropriate, and reflects the spatiotemporal variability of the relationship between people and fire (McWethy et al, 2013).…”

Locating Charcoal Production Sites in Sweden Using LiDAR, Hydrological Algorithms, and Deep Learning

“…The methods applied for automated feature detection are widely varied, especially for landscape-scale datasets such as LiDAR and satellite imagery [23][24][25][26][27]. Among the many advances made by scholars in the past few years, the use of morphological characteristics and object-based classifiers has been widely applied, especially to LiDAR data (see [13]). More recently, developments in deep learning (DL) have made progress in improving the accuracy of automated prospection of archaeological materials (e.g., [17]).…”

“…Charcoal production sites (sometimes referred to as relict charcoal hearths [RCHs]) are studied across Europe and North America, increasingly via LiDAR and LiDAR-derived products (e.g., [12][13][14][15]). RCHs provide key insight not only to past economic activities, but also the environmental impacts of industrialization in Europe and the United States, where charcoal and iron production were central industries [13,[16][17][18]. Many of these RCHs are located deep within forests, and thus LiDAR has aided in their detection at increasing rates over the past decade.…”

“…Thus, our case study has implications for archaeologists around the world where automated site prospection is hampered by limited available training datasets. Particularly among studies of RCHs in Europe and North America, our methods can aid in the documentation of broad landscapes under tree canopies where these features are often abundant but poorly recognized on a landscape scale [13]. Using depression algorithms, we can (1) allow for relatively good initial assessment of certain archaeological features, identifying dozens to hundreds of these deposits.…”

Multiproxy Holocene Fire Records From the Tropical Savannas of Northern Cape York Peninsula, Queensland, Australia

“…However, the interpretation and application of paleoecological findings to modern and future landscape management is still in its infancy. While regional and global approaches to trends in fire activity are useful for understanding long-term trajectories in wildfire activity (Marlon et al, 2015), more local approaches are needed for studies of past fire to be interpretable in a way that is applicable to modern management issues (e.g., Carter et al, 2021). Delivering on the promise of paleoecology still requires experimentation in Australia.…”