TY - JOUR
T1 - Fire regime on a cultural landscape
T2 - Navajo Nation
AU - Whitehair, Lionel
AU - Fulé, Peter Z.
AU - Meador, Andrew Sánchez
AU - Azpeleta Tarancón, Alicia
AU - Kim, Yeon Su
N1 - Publisher Copyright:
© 2018 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.
PY - 2018/10
Y1 - 2018/10
N2 - Fire has played an important role in the evolutionary environment of global ecosystems, and Indigenous peoples have long managed natural resources in these fire-prone environments. We worked with the Navajo Nation Forestry Department to evaluate the historical role of fire on a 50 km2 landscape bisected by a natural mountain pass. We used fifty 5-ha circular plots to collect proxy fire history data on fire-scarred trees, stumps, logs, and snags in a coniferous forest centered on a key mountain pass. The fire history data were categorized into three groups: All (all 50 plots), Corridor (25 plots closest to Buffalo Pass drainage), and Outer (remaining 25 plots, farther from pass). We assessed spatial and temporal patterns of fire recurrence and fire-climate relationships. The landscape experienced frequent fires from 1644, the earliest fire date with sufficient sample depth, to 1920, after which fire occurrence was interrupted. The mean fire interval (MFI) for fire dates scarring 10% or more of the samples was 6.25 years; there were 13 large-scale fires identified with the 25% filter with an MFI of 22.6 years. Fire regimes varied over the landscape, with an early reduction in fire occurrence after 1829, likely associated with pastoralism, in the outer uplands away from the pass. In contrast, the pass corridor had continuing fire occurrence until the early 20th century.Synthesis. Fires were synchronized with large-scale top-down climatic oscillations (drought and La Niña), but the spatially explicit landscape sampling design allowed us to detect bottom-up factors of topography, livestock grazing, and human movement patterns that interacted in complex ways to influence the fire regime at fine scales. Since the early 20th century, however, fires have been completely excluded. Fuel accumulation in the absence of fire and warming climate present challenges for future management.
AB - Fire has played an important role in the evolutionary environment of global ecosystems, and Indigenous peoples have long managed natural resources in these fire-prone environments. We worked with the Navajo Nation Forestry Department to evaluate the historical role of fire on a 50 km2 landscape bisected by a natural mountain pass. We used fifty 5-ha circular plots to collect proxy fire history data on fire-scarred trees, stumps, logs, and snags in a coniferous forest centered on a key mountain pass. The fire history data were categorized into three groups: All (all 50 plots), Corridor (25 plots closest to Buffalo Pass drainage), and Outer (remaining 25 plots, farther from pass). We assessed spatial and temporal patterns of fire recurrence and fire-climate relationships. The landscape experienced frequent fires from 1644, the earliest fire date with sufficient sample depth, to 1920, after which fire occurrence was interrupted. The mean fire interval (MFI) for fire dates scarring 10% or more of the samples was 6.25 years; there were 13 large-scale fires identified with the 25% filter with an MFI of 22.6 years. Fire regimes varied over the landscape, with an early reduction in fire occurrence after 1829, likely associated with pastoralism, in the outer uplands away from the pass. In contrast, the pass corridor had continuing fire occurrence until the early 20th century.Synthesis. Fires were synchronized with large-scale top-down climatic oscillations (drought and La Niña), but the spatially explicit landscape sampling design allowed us to detect bottom-up factors of topography, livestock grazing, and human movement patterns that interacted in complex ways to influence the fire regime at fine scales. Since the early 20th century, however, fires have been completely excluded. Fuel accumulation in the absence of fire and warming climate present challenges for future management.
KW - Diné
KW - Indigenous
KW - climate
KW - drought
KW - fire history
KW - tribal lands
KW - wildfires
UR - http://www.scopus.com/inward/record.url?scp=85053370113&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85053370113&partnerID=8YFLogxK
U2 - 10.1002/ece3.4470
DO - 10.1002/ece3.4470
M3 - Article
AN - SCOPUS:85053370113
SN - 2045-7758
VL - 8
SP - 9848
EP - 9858
JO - Ecology and Evolution
JF - Ecology and Evolution
IS - 19
ER -