Hydrologic and Geomorphological Assessment of Restoration

Transcription

Hydrologic and Geomorphological Assessment of Restoration
Resource Brief
Sky Island Restoration Cooperative
Fiscal Year 2015
The Sky Island Restoration Cooperative (SIRC) is a coalition of restoration practitioners, scientists, and
land managers, working together to restore the ecological processes and systems of the Sky Islands in the
Madrean Archipelago of the US-Mexico Borderlands.
Hydrologic and Geomorphological Assessment of Restoration
USGS, BLM, Stream Dynamics, Borderlands Restoration, Univ. of Arizona
Abstract
The USGS and its partners are carrying
out assessments of the hydrologic and
geomorphological changes induced by streamchannel and riparian restoration at two sites:
Vaughn Canyon near Elgin and Silver Creek in the
San Bernardino Valley. Preliminary results indicate
that site characteristics such as geologic substrate,
watershed characteristics, and soil-hydraulic
properties must be taken into account during
restoration planning, monitoring, and assessment.
Keywords
Infiltration, geomorphology, geophysics, isotope
geochemistry, restoration, monitoring, water and
soil detention structures
Project Background
A number of methods have become available that
allow for monitoring and assessment at multiple
scales of the hydrologic and geomorphologic
changes induced by restoration structures.
Measurements of streamflow, soil-moisture, and
infiltration are used in conjunction with models to
estimate local impacts to the water budget and the
response of channel morphology.
USGS scientist James Callegary and UA Master’s student Chloe Fandel
installing wildlife cameras to track streamflow
at Vaughn Canyon, Babocomari Ranch / USGS
RTK GPS and terrestrial- LiDAR and drone-based
photogrammetry structure from motion (SfM)
data to assess geomorphologic changes. The USGS
is combining repeat photography, in-channel
water stage, and subsurface temperature variation
to assess streamflow, and infiltration rates and
volumes.
We are also using electrical resistance tomography
and electromagnetic induction (EMI) to determine
subsurface structure and spatiotemporal watercontent variability and isotopic analysis of bed
sediments to assess changes in carbon and nitrogen
Project Activities and Outcomes
cycling and storage. Electromagnetic Induction
We report on results from a multidisciplinary,
(EMI) can give information on soils, geology,
multi-scale approach to assess the interaction of
moisture, and salt content as well as information on
restoration methods with land management and
change in electrical conductivity. This is a simple
natural processes at two sites in southeast Arizona
and inexpensive way to document that there are
(Silver Creek in the San Bernardino Valley, and
Vaughn Canyon near Elgin). Local-scale techniques water content changes at depth and to give an
approximate depth of percolation.
include high-resolution topographic surveys from
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to landscape characteristics, including geologic
substrate, watershed characteristics, and soilhydraulic properties.
USGS scientist Tom Porter taking LiDAR measurements
at Silver Creek in the San Bernardino Valley / USGS
Stream-gaging, and rainfall-runoff and hydraulic
modeling are being used to evaluate hydrologic
and geomorphologic changes occurring at both
local and landscape scales. Preliminary results
indicate that methods to support restoration
planning, monitoring, and assessment must be
tailored not only to the scale, information needs,
and scope of the individual project, but also
USGS scientists Jeff Cordova and Tom Porter installing
a continuous-slope area streamgage at Silver Creek in
the San Bernardino Valley / USGS
Stakeholder Involvement
USGS is coordinating field work with and
receives financial assistance from the BLM.
BLM also contributed personnel to carrying out
geophysical and sUAS surveys at Silver Creek
in the San Bernardino Watershed. USGS, with
UA professors and students, has installed an
infiltration monitoring system in Vaughn Canyon
at Babocomari Ranch (discussed in a companion
briefing on Vaughn Canyon). UA has also assisted
in carrying out geophysical and RTK-GPS
surveys. The restoration projects were completed
by Borderlands Restoration, BLM, and Stream
Dynamics.
Funding
BLM contributed $100,000 for the Silver Creek
project and Walton Foundation (via Borderlands
Restoration) contributed as well (funding amount
was listed with Babocomari work elsewhere). USGS
contributed $40K in-kind. Total project value was
approximately $140,000.
University of Arizona Professor Ty Ferre augering a hole to assess
particle size distribution and hydraulic conductivity
in Vaughn Canyon. EMI instrument at left. / USGS
Sky Island Restoration Cooperative
Multidisciplinary watershed restoration research
Editor: James Callegary, Chloe Fandel
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