2005 Progress Report: Remote Sensing of Water Quality

EPA Grant Number: R829458C001
Subproject: this is subproject number 001 , established and managed by the Center Director under grant R829458
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: EAGLES - Consortium for Estuarine Ecoindicator Research for the Gulf of Mexico
Center Director: Brouwer, Marius
Title: Remote Sensing of Water Quality
Investigators: Han, Luoheng
Institution: University of Alabama , University of Southern Mississippi
EPA Project Officer: Hiscock, Michael
Project Period: December 1, 2001 through November 30, 2005 (Extended to May 20, 2007)
Project Period Covered by this Report: December 1, 2004 through November 30, 2005
RFA: Environmental Indicators in the Estuarine Environment Research Program (2000) RFA Text |  Recipients Lists
Research Category: Water , Ecosystems , Ecological Indicators/Assessment/Restoration

Objective:

Hyperspectral sensing of chlorophyll α(chlorophyll α) in Pensacola Bay continued in the fourth year of the “Remote Sensing of Water Quality” project. In addition, hyperspectral sensing of biofilms was conducted. This is part of a collaborative effort between the University of Alabama (UA) and the University of West Florida (UWF) to explore the applications of remote sensing to other components of the Consortium for Estuarine Ecoindicator Research for the Gulf of Mexico (CEER-GOM). The main goal of this joint endeavor was to develop a practical tool for estimating chlorophyll concentration of biofilms using spectral reflectance. Findings from the study include the utility of the first derivative spectra and the best wavelengths for determining chlorophyll content of biofilms. Two articles were published in the International Journal of Remote Sensing during the period of this report.

The objectives are to: (1) continue hyperspectral sensing of chlorophyll α in Pensacola Bay; and (2) estimate chlorophyll α of biofilms using hyperspectral sensing technique.

Progress Summary:

Hyperspectral Sensing of Chlorophyll α

Close-range hyperspectral sensing was conducted, in collaboration with Dick Snyder’s crew from UWF, in August 26, 2006, over Pensacola Bay. Surface spectral reflectance data were collected over 14 of 16 of the Gulf Ecology Division’s monthly sampling locations. Water sampling data were simultaneously collected and tested in the laboratory for chlorophyll αand other water quality parameters. The chlorophyll αconcentrations ranged from 0.85 at P1 to 11.45 μg L-1 at P4. Figure 1 shows the surface re flectance curves.

The surface reflectance curves

Figure 1

Derivative analysis was performed of the surface reflectance spectra. Figure 2 shows the correlation between first derivative and chlorophyll α concentration.

The correlation between first derivative and chlorophyll a concentration

Figure 2

The best spectral band for estimating chlorophyll αwas found at 686 nm (Figure 3), which is consistent with the results from 2002 and 2003.

The best spectral band for estimating chlorophyll a was found at 686 nm

Figure 3

Hyperspectral Sensing of Biofilms

The hyperspectral sensing of biofilms was a collaborative effort between Luoheng Han of UA and Richard Snyder of UWF. The purpose was to develop a practical tool to characterize the biofilms using measured chlorophyll concentrations and spectral reflectance. The experiments were conducted in the laboratory of UWF (Photos 1 and 2).

The hyperspectral sensing of biofilms

Figures 4, 5, and 6 show the spectral reflectance between 400 and 900 nm for 20 bottom and 34 surface biofilms deployed in different locations (open bay and marsh creeks), in Pensacola Bay. These biofilms were placed, maintained, and collected by UWF as a part of the biofilm component of CEER-GOM. Although the reflectance values seem to be weakly associated with the chlorophyll αconcentrations of the biofilms, the shapes/slopes of the reflectance curves do contain the chlorophyll αinformation.

The spectral reflectance between 400 and 900 nm for 20 bottom and 34 surface biofilms deployed in different locations, in Pensacola Bay

Figure 4

The spectral reflectance between 400 and 900 nm for 20 bottom and 34 surface biofilms deployed in different locations, in Pensacola Bay

Figure 5

The spectral reflectance between 400 and 900 nm for 20 bottom and 34 surface biofilms deployed in different locations, in Pensacola Bay

Figure 6

Derivative spectra and correlation analysis were performed between the first derivative and chlorophyll αof biofilms. Figure 7 highlights the result for both surface and bottom biofilms. The highest R (0.9) was found at 448 nm for the bottom biofilms, while -0.8 (R) was found at 748 nm for the surface biofilms. When the two datasets were combined, the wavelength of 655 nm appeared to offer the best correlation (R = -0.69). Figures 8 and 9 indicate that the first derivative spectra show promise for estimating chlorophyll αcontent of the biofilms.

The result for both surface and bottom biofilms

Figure 7

The result for both surface and bottom biofilms

Figure 8

The result for both surface and bottom biofilms

Figure 9


Journal Articles on this Report : 2 Displayed | Download in RIS Format

Other subproject views: All 8 publications 2 publications in selected types All 2 journal articles
Other center views: All 171 publications 54 publications in selected types All 48 journal articles
Type Citation Sub Project Document Sources
Journal Article Han LH, Jordan KJ. Estimating and mapping chlorophyll-a concentration in Pensacola Bay, Florida using Landsat ETM+ data. International Journal of Remote Sensing 2005;26(23):5245-5254. R829458C001 (2004)
R829458C001 (2005)
not available
Journal Article Han LH. Estimating chlorophyll-a concentration using first-derivative spectra in coastal water. International Journal of Remote Sensing 2005;26(23):5235-5244 R829458C001 (2004)
R829458C001 (2005)
not available

Supplemental Keywords:

RFA, Scientific Discipline, ECOSYSTEMS, Geographic Area, Water, Ecosystem Protection/Environmental Exposure & Risk, Aquatic Ecosystems & Estuarine Research, Ecology, estuarine research, Ecosystem/Assessment/Indicators, Ecosystem Protection, Aquatic Ecosystem, Aquatic Ecosystems, Environmental Monitoring, Ecological Monitoring, Ecology and Ecosystems, Gulf of Mexico, Ecological Indicators, monitoring, ecoindicator, ecological exposure, remote sensing, estuaries, estuarine integrity, Mobile Bay, Galveston Bay, CEER-GOM, Apalachicola Bay, estuarine ecoindicator, environmental indicators, environmental stress, estuarine waters, restoration, water quality

Relevant Websites:

http://www.usm.edu/gcrl/ceer_gom/ Exit

Progress and Final Reports:

Original Abstract
  • 2002 Progress Report
  • 2003 Progress Report
  • 2004 Progress Report
  • 2006
  • Final

  • Main Center Abstract and Reports:

    R829458    EAGLES - Consortium for Estuarine Ecoindicator Research for the Gulf of Mexico

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R829458C001 Remote Sensing of Water Quality
    R829458C002 Microbial Biofilms as Indicators of Estuarine Ecosystem Condition
    R829458C003 Individual Level Indicators: Molecular Indicators of Dissolved Oxygen Stress in Crustaceans
    R829458C004 Data Management and Analysis
    R829458C005 Individual Level Indicators: Reproductive Function in Estuarine Fishes
    R829458C006 Collaborative Efforts Between CEER-GOM and U.S. Environmental Protection Agency (EPA)-Gulf Ecology Division (GED)
    R829458C007 GIS and Terrestrial Remote Sensing
    R829458C008 Macrobenthic Process Indicators of Estuarine Condition for the Northern Gulf of Mexico
    R829458C009 Modeling and Integration