The extensive tidal wetlands and mudflats of the Delaware Estuary are complex environmental systems that provide critical hydrological, geochemical, and ecological functions for the State of Delaware (e.g. flood attenuation, water quality, nursery for marine life). Collecting the data needed to quantify processes in this critical zone while not altering its environment is extremely difficult due to soft sediment, shallow water, and the flooding and ebbing of tides. Remote sensing is a viable alternative, but the typical low-frequency acquisition of imagery from satellite and aerial platforms limits its applicability in process-based research in an environment where high-frequency variations are the norm (e.g. exposure/inundation, changes in moisture content, presence/absence of algal mats).
To overcome this limitation, we are developing an innovative ground-based imaging system to collect multi-spectral imagery (visible, near and thermal infrared bands) at time-scales (minutes/hours) below those of the dominant processes in intertidal environments (semi-diurnal tides, day/night). A modular system based on mature imaging technology is being assembled for science missions by foot, boat, truck, tower, and lift. This project consists of some critical laboratory studies to test our conceptual framework.
We are investigating the effects of viewing geometry and the relationships between imagery and sediment properties (lithology, moisture content) under simulated conditions of exposure/inundation and radiant heating. The work will catalyze an exciting new multidisciplinary collaboration that takes advantage of the PIs’ expertise in thermography, ground-based imaging and coastal geology/hydrology/engineering. The imaging system and associated analytical techniques could have broad value for research in the critical zone, a major focus of the UD Delaware Environmental Institute (DENIN).
The proposed imaging system is a tool that helps scientists doing process-based research in dynamic and spatially heterogeneous environments. It could be used to quantify temporal changes in spatial patterns, quantify temporal changes at many points (every pixel can yield a time series), and to set varying spatial and temporal boundary conditions in numerical models of processes. We also easily see how the system could be used to address environmental issues relevant to the State including water quality, wetland loss, point and nonpoint source pollution, contaminated sites, habitat degradation, coastal erosion, oil spills, and deteriorating sewer and water infrastructure.
This project was partially funded by the Delaware EPSCoR program as part of a Research Infrastructure and Improvement (RII) grant from the National Science Foundation and by the Delaware Space Grant Consortium as part of an EPSCOR Research Infrastructure Development (RID) grant from NASA. EPSCoR, the Experimental Program to Stimulate Competitive Research, is a federal grant program that helps states develop research capabilities and institutions.