Lukachukai - USLUK001
Whitehair, Lionel; Fulé, Peter Z.; Sánchez Meador, Andrew, Azpeleta Tarancón A.; Yeon-Su, Kim

Dating method: crossdated

Sample storage location: Northern Arizona University, School of Forestry, 200 East Pine Knoll Drive, Flagstaff, Arizona 86011 (Pete.Fule@nau.edu, 928-523-6636)

Reference: 
Whitehair, L., Fulé, P.Z., Sanchez Meador, A.J.,  Begay Jr,  M.A. 2017. FIRE REGIME ON A CULTURAL LANDSCAPE: NAVAJO NATION. Thesis.

Abstract: 
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. Increasing severity of large wildfires in the southwestern U.S. affects both tribal and non-tribal lands in the region, but tribal forests are substantially underrepresented in terms of fire regime studies. We worked with the Navajo Nation Forestry Department to evaluate the historic role of fire on a 50 km 2 landscape bisected by a natural mountain pass in the Lukachukai Mountains. We used fifty 5-ha circular plots in order to collect proxy fire history data on fire-scarred trees, stumps, logs, and snags in a coniferous forest. 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 to the north and south, 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, when the fire regime was completely interrupted. The mean fire interval (MFI) for fire dates scarring 10% or more of the samples was 6.25 years; there were also 13 large-scale fire events fires identified with the 25% filter with an MFI of 22.6 yrs. 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 by 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.

Reference: 
Whitehair,  L., Fulé, P.Z., Sanchez Meador, A.J.,  Azpeleta Tarancón, A., Yeon-Su, K. 2018. Fire regime on a cultural landscape: Navajo Nation. Ecology and Evolution. 8:9848–9858. DOI 10.1002/ece3.4470     

Abstract: 
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.

NOAA/IMPD web landing page for this fire history site is available at:
https://ncdc.noaa.gov/paleo/study/26010

NOAA/IMPD DIF and JSON metadata records for this fire history site are available at:
https://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-fire-26010.xml and https://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/json/noaa-fire-26010.json

FHX filename: usluk001.fhx

IMPD code: USLUK001

Name of site: Lukachukai

Site code: LUKA

Contributors: Whitehair, Lionel; Fulé, Peter Z.; Sánchez Meador, Andrew, Azpeleta Tarancón A.; Yeon-Su, Kim

Latitude: 36.468006 (WGS84)

Longitude: -109.154961 (WGS84)

Mean elevation: 3025 (meters)

Country: United States

State: Arizona

Region: northeast Arizona

First year: 1388 AD

Last year: 2015 AD

Species name: Pinus ponderosa [PIPO], Pseudotsuga menziesii [PSME]

Funding agency names and grant numbers: 
United States Department of Agriculture, National Institute of Food and Agriculture (grant # 2015-67019-23185), McIntire-Stennis appropriations to Northern Arizona University and the state of Arizona

Comments:
This site was sampled to reconstruct historical fire regimes on the Chuska mountain range located in northeast Arizona.

Fire History Graphs: Fire History Graphs illustrate specific years when fires occurred and how many trees were scarred. They are available in both PDF and PNG formats. The graphs consist of 2 parts, both of which show the X axis (time line) at the bottom with the earliest year of information on the left and the latest on the right. The Fire Index Plot is the topmost plot, and shows two variables: sample depth (the number of recording trees in each year) as a blue line along the left Y axis, compared with the percent trees scarred shown as gray bars along the right Y axis. Below, the Fire Chronology Plot consists of horizontal lines representing injuries by year on individual sampled trees. Symbols are overlain that denote the years containing the dendrochronologically-dated fire scars or injuries. The sample ID of each tree is displayed to the right of each line. The Composite Axis below represents the composite information from all individual series. The symbols used to represent the fire scars or injuries, and the filters used to determine the composite information, are shown in the legend. These graphs were created using the Fire History Analysis and Exploration System (FHAES). See http://www.fhaes.org for more information.