Systematic grid demographic monitoring of aspen

Knowledge graph centered on Systematic grid demographic monitoring of aspen with 72 nodes and 161 connections. Top connected: Rocky Mountain Biological Laboratory, Gothic, Crested Butte, Engelmann Spruce, Colorado East River Valley.

Method synopsis

Systematic establishment of gridded plots across watersheds followed by long-term monitoring of tagged individual trees for mortality and recruitment rates. Combined with environmental characterization of each plot.

Synthesized from method descriptions across 6 papers using this protocol.

Procedure from a recent peer-reviewed implementation

Steps below were extracted from the most recent peer-reviewed implementation of this protocol in the corpus — Cytotype and genotype predict mortality and recruitment in Colorado quaking aspen (<i> Populus tremuloides </i>) (2021), Ecological Applications. The protocol was originally introduced by What determines the distribution of red-naped sapsuckers in the East River Valley? (2008). Implementations in other papers (listed below) may differ.

1. Establish study plots
   Established 503 plots in summer 2018 across southwestern Colorado watersheds. Gridded plots: selected 70 plots per watershed (280 total) in hand-selected regions with high clonal diversity based on autumn foliage heterogeneity in Google Earth imagery, using 25-meter rectangular spacing pattern covering ~4 hectares each. Random plots: located ~45 plots per watershed (194 total) in areas with aspen forest cover on non-wilderness US Forest Service or private conservation land on slopes <40 degrees. Opportunistic plots: ~7 plots per watershed (29 total) visually selected for high mortality or low recruitment to improve demographic statistical balancing.
   Quantities: 503 total plots: 280 gridded, 194 random, 29 opportunistic across 4 watershedsDuration: Summer 2018Conditions: Southwestern Colorado, drought-affected region, aspen forest areas
   Equipment: Google Earth imagery, GIS software, GPS units (Trimble, Geo7X)
2. Relocate and finalize plot positions
   Plots relocated from pre-chosen coordinates if found to be in small clearings. In such cases, chose nearest forest patch with at least 5m buffer to the clearing. Final plot coordinates measured using GPS units with nominal sub-meter resolution (in practice 1-2 meters due to topography and canopy cover). Each plot centered at a living, standing aspen stem minimum 5cm diameter at breast height, which was permanently tagged.
   Quantities: 503 plots, minimum 5cm DBH focal trees Summer 2018

Typical Equipment

• GPS units for plot positioning
• tree tags
• GPS units or measuring devices for spatial coordinates
• GPS units for elevation
• clinometer for slope
• compass for aspect
• soil sampling tools
• data recording sheets
• replacement tags for new recruits

Output Measurements

• mortality rates
• recruitment rates
• environmental variables

Papers Using This Protocol (6)

Species Studied With This Protocol

Places Where Used