Native American depopulation, reforestation, and fire regimes in the Southwest United States, 1492–1900 CE

Abstract

Native American populations declined between 1492 and 1900 CE, instigated by the European colonization of the Americas. However, the magnitude, tempo, and ecological effects of this depopulation remain the source of enduring debates. Recently, scholars have linked indigenous demographic decline, Neotropical reforestation, and shifting fire regimes to global changes in climate, atmosphere, and the Early Anthropocene hypothesis. In light of these studies, we assess these processes in conifer-dominated forests of the Southwest United States. We compare light detection and ranging data, archaeology, dendrochronology, and historical records from the Jemez Province of New Mexico to quantify population losses, establish dates of depopulation events, and determine the extent and timing of forest regrowth and fire regimes between 1492 and 1900. We present a new formula for the estimation of Pueblo population based on architectural remains and apply this formula to 18 archaeological sites in the Jemez Province. A dendrochronological study of remnant wood establishes dates of terminal occupation at these sites. By combining our results with historical records, we report a model of pre- and post-Columbian population dynamics in the Jemez Province. Our results indicate that the indigenous population of the Jemez Province declined by 87% following European colonization but that this reduction occurred nearly a century after initial contact. Depopulation also triggered an increase in the frequency of extensive surface fires between 1640 and 1900. Ultimately, this study illustrates the quality of integrated archaeological and paleoecological data needed to assess the links between Native American population decline and ecological change after European contact.

Socioecological transitions trigger fire regime shifts and modulate fire–climate interactions in the Sierra Nevada, USA, 1600–2015 CE

“…In Colorado, fire activity did not change until the mid-to late 19th century with widespread Euro-American settlement (22), and it increased rather than decreased, as in the Sierra Nevada. In the early to mid-17th century, fire extent increased when Spanish missions were established in the American Southwest (52) and in Northwestern Mexico in the late 18th century when missions were abandoned (40). As in the Sierra Nevada, reduced Native American burning and increased fuels are implicated in the fireregime shifts.…”

Living on a flammable planet: interdisciplinary, cross-scalar and varied cultural lessons, prospects and challenges

“…From transnational Earth system impacts [1], to domestic impacts on sovereign nations [2], to impacts on local communities [3] and the individuals who make up communities, the perceptions, decisionmaking and prioritization of policy goals are built upon cultural and historical experiences [4][5][6] that have legacy effects, lags and feedbacks across temporal scales [7][8][9][10][11][12]. Although there is a growing literature on building fire-adapted communities [13,14], it is important to recognize that there is both heterogeneity and variability in the historical, technological, cultural and environmental contexts in which humans perceive and respond to fire challenges [15], and that in turn these have cross-scalar feedbacks through sociopolitical structures [2,16], intergenerational cultural transmission [5], historical ecology of landscapes and biomes [12,17,18], and even fire-atmosphere-climate feedbacks [19][20][21].…”

Holocene peatland and ice-core data constraints on the timing and magnitude of CO2emissions from past land use

“…Forest regrowth on previously cultivated land has been suggested to sequester enough C to explain observed variations in atmospheric CO 2 composition (43,44), and the CO 2 dip may therefore serve as a geological marker for the beginning of the Anthropocene (2). However, this link has been put into question on several grounds (45)(46)(47)(48). Land-use reconstructions applied here cover the range of this uncertainty and simulated CO 2 emissions bracket earlier non-model-based estimates (43,44).…”