Assessing hydrologic function, plant stress, and success of bottomland restoration using UAS
Midwest bottomland sites are being restored to hardwood forests via various methods. Assessment of success following restoration to forested conditions requires rapid, short-term assessment tools that can indicate long-term trajectory based on short-term community development.
High-resolution aerial photography at critical times enables monitoring of individual planted stems to assess mortality and varying success according to modeled and measured abiotic factors. At three sites in NE Indiana during 2016, this project seeks to:
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test the efficacy of high-resolution data to monitor individual stem survival
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relate species’ stem survival to hydrology for sites characterized by short-duration flow events
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identify photogrammetric indicators of plant stress associated with short-duration flow events
-
validate modeled hydrology (extent and duration of flooding) using high-resolution aerial photographs
-
identify photogrammetric indicators of above-ground carbon stocking with ground validation
UAS allow data acquisition coincident with short-duration floods, and can be used with vegetation indices (NDVI, GRVI, RVI, etc.) to assess plant response to these events. For flashy streams, satellite-based data often fails to capture sites during floods when plant physiological response is likely to be most profound. Satellite data may also fail to detect the extent of flooding, limiting our ability to relate stress to the specific hydrologic attributes (extent, depth, duration). Tethered aerial sensors may be functional during early stages of restoration, but will not be functional in full-canopied forests. The greatest logistic obstacle for UAS deployment in support of this project will be anticipating storm events likely to induce flooding in sufficient time to allow travel and equipment preparation. We will use time-targeted UAS-derived data to validate modeled hydrology during short-lived floods, and simultaneously provide information about plant stress relating to these events. We will use high-resolution multispectral imagery combined with individual stem mapping to detect individual species’ responses to flood events in relation to the depth and duration of flooding on various soil types. UAS-derived data will be paired with site-specific hydrologic data collected on the ground to enable validation of flood-extent modeling based on local river stage and assessment of groundwater-plant condition relationships. UAS-derived data will be complemented by ground-measured climatic data (radiation index, temperature, humidity, etc.) to relate plant stress to climatic conditions. For non-flooding periods, UAS data and structure-from-motion derived products will be compared to estimates of carbon-load derived from plot data to determine if photogrammetric methods are appropriate for estimating carbon sequestration on restored sites.
Midwest bottomland sites are being restored to hardwood forests via various methods. Assessment of success following restoration to forested conditions requires rapid, short-term assessment tools that can indicate long-term trajectory based on short-term community development.
High-resolution aerial photography at critical times enables monitoring of individual planted stems to assess mortality and varying success according to modeled and measured abiotic factors. At three sites in NE Indiana during 2016, this project seeks to:
-
test the efficacy of high-resolution data to monitor individual stem survival
-
relate species’ stem survival to hydrology for sites characterized by short-duration flow events
-
identify photogrammetric indicators of plant stress associated with short-duration flow events
-
validate modeled hydrology (extent and duration of flooding) using high-resolution aerial photographs
-
identify photogrammetric indicators of above-ground carbon stocking with ground validation
UAS allow data acquisition coincident with short-duration floods, and can be used with vegetation indices (NDVI, GRVI, RVI, etc.) to assess plant response to these events. For flashy streams, satellite-based data often fails to capture sites during floods when plant physiological response is likely to be most profound. Satellite data may also fail to detect the extent of flooding, limiting our ability to relate stress to the specific hydrologic attributes (extent, depth, duration). Tethered aerial sensors may be functional during early stages of restoration, but will not be functional in full-canopied forests. The greatest logistic obstacle for UAS deployment in support of this project will be anticipating storm events likely to induce flooding in sufficient time to allow travel and equipment preparation. We will use time-targeted UAS-derived data to validate modeled hydrology during short-lived floods, and simultaneously provide information about plant stress relating to these events. We will use high-resolution multispectral imagery combined with individual stem mapping to detect individual species’ responses to flood events in relation to the depth and duration of flooding on various soil types. UAS-derived data will be paired with site-specific hydrologic data collected on the ground to enable validation of flood-extent modeling based on local river stage and assessment of groundwater-plant condition relationships. UAS-derived data will be complemented by ground-measured climatic data (radiation index, temperature, humidity, etc.) to relate plant stress to climatic conditions. For non-flooding periods, UAS data and structure-from-motion derived products will be compared to estimates of carbon-load derived from plot data to determine if photogrammetric methods are appropriate for estimating carbon sequestration on restored sites.