DOI: 10.5061/dryad.qfttdz0r3
title: Data from: Reach-scale geomorphic characteristics influencing post-fire river response in mountain streams, Colorado, USA

description: Numerous 3rd-order mountain catchments within the Cache la Poudre (Poudre)
 River basin in the Colorado Front Range, USA burned severely and
 extensively during the 2020 Cameron Peak fire. Many of these catchments
 experienced debris flows and flash floods triggered by convective storms
 after the fire. The downstream effects of the debris flow sediment varied
 along a continuum from attenuated and largely contained within the
 catchment, through contributing to a pre-existing debris fan at the
 catchment outlet, to releasing substantial volumes of water and sediment
 to the Poudre River. We conducted longitudinally continuous surveys within
 seven of these catchments to measure reach-scale characteristics. These
 characteristics quantify the reach-scale geomorphic, vegetation, and burn
 characteristics, with a particular focus on elements that introduce inter-
 and intra-reach spatial heterogeneity including channel planform, beaver
 modified topography, the distribution of channel and floodplain logjam
 distribution density, and the floodplain width/channel width ratio for the
 population of reaches within each catchment.
description: We conducted a longitudinal reach survey within each study
 catchment. The survey started at the drainage divide, moving downhill to
 find the first evidence of channelization and follow it to the stream
 head. We followed the river downstream, defining the boundaries between
 reaches by field-observed relative valley and channel geometry using a
 Garmin GPSMAP 66st and a Garmin eTrex10 with 3-m horizontal accuracy.
 Within each reach I documented burn status, vegetation type, basal area,
 channel planform, channel bedform, bankfull width, floodplain width,
 number of channel and floodplain jams, and number of beaver berms. Burn
 status was documented categorically in the field as burned, unburned, or
 mixed. Vegetation type was noted categorically as conifer, willow, aspen,
 or herbaceous based on the species present, where herbaceous denoted a
 lack of trees rather than implying that there was no herbaceous vegetation
 where other species were present. Basal area of the river corridor forest
 was measured with a Panama Angle Gauge at approximately one channel width
 away from bankfull. All standing trees (living and dead) were included.
 Channel planform and channel bedform were determined categorically.
 Bankfull channel and floodplain widths were measured using a Laser
 Technology TruPulse 360B laser range finder and high-water marks
 indicative of high flows from the most recent spring snowmelt flows.
 Logjams were designated as at least three pieces of wood in contact, with
 each piece of wood at least 1 m in length and 10 cm in diameter. Jams
 within the bankfull channel were tallied as channel jams and jams outside
 of the bankfull channel but within the bounds of high-water marks were
 tallied as floodplain jams. The presence of beaver berms was tallied
 within each reach where clearly defined individual berms existed. Where
 there were complex beaver meadows, beaver modified terrain was noted as
 “beaver meadow,” indicating many berms that were not distinct throughout
 the length of the reach.
description: # Data from: Reach-scale geomorphic characteristics influencing post-fire
 river response in mountain streams, Colorado, USA Reach-scale parameters
 collected in the field during longitudinal surveys. Each reach is a
 segment of river corridor that has common geometry (i.e. continuous valley
 width, slope, etc) or is bounded by the confluence with a tributary. Data
 were collected in the summer of 2023 at sites that burned in the Cameron
 Peak fire in 2020. ## Description of the data and file structure
 ReachVariableKey: a table that defines each of the variables for each
 reach including category, variable name, units if applicable, description
 of methods, and format. ReachData: a file with variables for each reach.
 Reach boundaries are coordinates for the upstream point of each reach. The
 downstream boundary is the upstream reach coordinate of the next most
 downstream reach. Reaches are numbered using reach IDs which are made up
 of a site code (LBC for Little Beaver Creek) and a number indicating its
 relative position downstream. Reach 01 in any catchment is the
 upstream-most reach of that site. Cells with "NA" are data that
 were not collected in the field. This research was conducted on the
 traditional and ancestral homelands of the Arapaho, Cheyenne, and Ute
 Nations and peoples. This was also a site of trade, gathering, and healing
 for numerous other Native tribes. Indigenous peoples are original stewards
 of this land and all the relatives within it.