Plant species richness at archaeological sites suggests ecological legacy of Indigenous subsistence on the Colorado Plateau

Abstract

Humans have both intentional and unintentional impacts on their environment, yet identifying the enduring ecological legacies of past small-scale societies remains difficult, and as such, evidence is sparse. The present study found evidence of an ecological legacy that persists today within an semiarid ecosystem of western North America. Specifically, the richness of ethnographically important plant species is strongly associated with archaeological complexity and ecological diversity at Puebloan sites in a region known as Bears Ears on the Colorado Plateau. A multivariate model including both environmental and archaeological predictors explains 88% of the variation in ethnographic species richness (ESR), with growing degree days and archaeological site complexity having the strongest effects. At least 31 plant species important to five tribal groups (Navajo, Hopi, Zuni, Ute Mountain Ute, and Apache), including the Four Corners potato (Solanum jamesii), goosefoot (Chenopodium sp.), wolfberry (Lycium pallidum), and sumac (Rhus trilobata), occurred at archaeological sites, despite being uncommon across the wider landscape. Our results reveal a clear ecological legacy of past human behavior: even when holding environmental variables constant, ESR increases significantly as a function of past investment in habitation and subsistence. Consequently, we suggest that propagules of some species were transported and cultivated, intentionally or not, establishing populations that persist to this day. Ensuring persistence will require tribal input for conserving and restoring archaeo-ecosystems containing “high-priority” plant species, especially those held sacred as lifeway medicines. This transdisciplinary approach has important implications for resource management planning, especially in areas such as Bears Ears that will experience greater visitation and associated impacts in the near future.

LegacyPollen 1.0: a taxonomically harmonized global late Quaternary pollen dataset of 2831 records with standardized chronologies

“…Human activities are an important driver of vegetation change, in addition to climate and other natural forces (Ellis and Ramankutty, 2008;Mottl et al, 2021;Pavlik et al, 2021). Deforestation during the Holocene period is of particular relevance, and, with the help of the LegacyPollen 1.0 dataset, this can now be investigated at the hemispheric scale.…”

Spatiotemporal variation in human settlements and their interaction with living environments in Neolithic and Bronze Age China

“…Human activity is an important force shaping the earth’s hydrosphere, atmosphere, and biosphere (Cooper et al, 2018; Ellis et al, 2021). The impact of human activities on the environment has been receiving increasing attention (Jenny et al, 2019; Pavlik et al, 2021; Zhang et al, 2021a). Since the concept of the “Anthropocene” was proposed (Crutzen, 2002), the anthropogenic impact has triggered extensive discussion and become a hotly debated topic (Ruddiman et al, 2020; Waters et al, 2018; Zalasiewicz et al, 2021).…”

Spatiotemporal Variations of Human Pressure on Key Biodiversity Areas in the Qinghai–Tibet Plateau: A Comparative Analysis

“…From 1990 to 2015, the total population of the Qinghai-Tibet Plateau increased from 6.58 to 9.13 million (Bao and Liu, 2019). Increased human activity alters the natural succession direction of ecosystems by changing species richness, accelerating biodiversity loss, and discharging wastewater, gas, and solids into the environment, which has far-reaching impacts on ecosystems (Mottl et al, 2021;Pavlik et al, 2021). In this study, areas with a greater population density often suffered more pressure.…”