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Person

Nathan R DeJager

Ecologist

Upper Midwest Environmental Sciences Center

Email: ndejager@usgs.gov
Office Phone: 608-781-6232
Fax: 608-783-6066
ORCID: 0000-0002-6649-4125

Location
UMESC - Laboratory/Office - #1
2630 Fanta Reed Road
La Crosse , WI 54603
USA

Supervisor: Jennifer S Sauer
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This data set consists of monthly averages of soil and litter properties. Rows are grouped in the following order: year, month, vegetation type, plot ID. Within a single month five plots were sampled within each of the 2 vegetation types (10 plots total). Columns F+ represent individual measurements.
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Floodplain inundation is believed to be the dominant physical driver of an array of ecosystem patterns and processes in the Upper Mississippi River System (UMRS). Here, we present the results of a geospatial surface-water connectivity model in support of ecological investigations fully described in the USGS Open File Report entitled “Indicators of Ecosystem Structure and Function for the Upper Mississippi River System” (De Jager et al., in review). Briefly, we identified likely instances of floodplain submergence by comparing a daily time series of gage-derived water surface elevations to topo-bathymetric data modified to account for slopes and hydrologic routing. The resulting raster attribute table contains columns...
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Floodplain inundation is believed to be the dominant physical driver of an array of ecosystem patterns and processes in the Upper Mississippi River System (UMRS). Here, we present the results of a geospatial surface-water connectivity model in support of ecological investigations fully described in the USGS Open File Report entitled “Indicators of Ecosystem Structure and Function for the Upper Mississippi River System” (De Jager et al., in review). Briefly, we identified likely instances of floodplain submergence by comparing a daily time series of gage-derived water surface elevations to topo-bathymetric data modified to account for slopes and hydrologic routing. The resulting raster attribute table contains columns...
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Premise of the study: Consistent with the self-thinning law of plant population ecology, Niklas et al. in 2003 proposed that stem size-density distributions (SDDs) of multispecies forest communities should change in very predictable ways as a function of the effects of past disturbances on average tree size. To date, empirical tests of this hypothesis have not been pursued in floodplain settings. Methods: SDDs were constructed using tree stem-size and density data from forest plots positioned along a flood frequency and duration gradient in the Upper Mississippi River floodplain. Key Results: As flooding (both frequency and duration) increased, several small tree species were eliminated from forest plots and...
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Geographic patterns can change through time and/or across space, and these changes can lead to differences in the movement pattern and body condition of organisms, their interactions with each other and their environment, and ultimately lead to population and community-level changes. When quantifying landscape patterns using remotely sensed data, it is important to recognize that each pixel (i.e. picture element) has a temporal and spatial context. A pixel’s temporal context refers to its past and present classification. The spatial context of a pixel depends on the classification of neighbouring pixels, and the size of the area considered as the neighbourhood. Despite the fact that pixels are the basic unit of...
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