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Trophic Classification of Selected Colorado Lakes

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Trophic Classification of Selected Colorado Lakes JPL PUBLICATION 78-100 EPA-600/4-79-005 Trophic Classification of Selected Colorado Lakes Ribhard J. Black-well Jet Propulsion Laboratory' Dale H. P. Boland U.S, EnvironmentahProtection Agency (NASA-CR-158500) TROPHIC CLASSIFICATION OF N79-22591 SELECTED COLORADO LAKES (Jet Propulsion Lab.) 210 p HC A10/HF A01 CSCL 08H Unclas G3/43 25085 January 197 SRIGINAL CONTAIRS 1Ol.R ILLUSMTr)h$s 'Prepared for - National Aer-onutics and Space Administration and U.S. Environmental Protection Agency Jet Propulsion Laboratory 4c, California, Institute of Technology Pasadena, California SUBJECT: Errata Please note the following corrections to JPL Publication 78-100, Trophic Classification of Selected Colorado Lakes, by Richard J. Blackwell and Dale H. P. Boland, dated January 1979: Page 5-1, paragraph (2): Line 1, change "MSS and MSS" to "MKS and MSS" Line 5, change "MSS-related" to "MMS-related" JPL PUBLICATION 78-100 tA-b00/4h79-005 TROPHIC CLASSIFICATION OF SELECTED COLORADO LAKES Lake Classification Through the Amalgamation of Contact-Sensed Data and Digitally Processed Multispectral Scanner Data Acquired by Satellite and Aircraft Richard J. Blackwell Dale H. P. Boland Earth Resources Application Group Water and Land Quality Branch Jet Propulsion Laboratory Environmental Monitoring and California Institute of Technology Support Laboratory - Las Vegas Pasadena, California National Aeronautics and U.S. Environmental Protection Agency Space Administration Office of Research and Development Washington, D.C. 20546 Las Vegas, Nevada 89114 January 1979 The research described in this report was carried out by the Jet Propulsion Laboratory, California Institute of Technology, together with the U. S. Environmental Protection Agency and was jointly sponsored by the National Aeronautics and Space Administration and the U. S. Environmental Protection Agency. • t \\ ABSTRACT Multispectral scanner data, acquired over several Colorado lakes contact­ using Landsat-1 and aircraft, were used in conjunction with lacus- sensed water quality data to determine the feasibility of assessing contact­ trine trophic levels. A trophic state index was developed using of sensed data for several trophic indicators (chlorophyll a, inverse total organic Secchi disc transparency, conductivity, total phosphorous, the digitally pro­ nitrogen, algal assay yield). Relationships between and the cessed multispectral scanner data, several trophic indicators, classification trophic index were examined using a supervised multispectral significant correlations technique and regression techniques. Statistically indicators (chlorophyll exist between spectral bands, several of the trophic and the trophic state a, Secchi disc transparency, total organic nitrogen), the spectral index. Color-coded photomaps were generated which depict acquired from satel­ aspects of trophic state. Multispectral scanner data in lake monitoring lite and aircraft platforms can be used to advantage data. and survey programs when amalgamated with contact-sensed iii CONTENTS 1-1 1. INTRODUCTION ----------------------------------------------- A. THE NATIONAL EUTROPHICATION SURVEY ------------------- 1-1 B. REQUIREMENTS OF THE FEDERAL WATER POLLUTION CONTROL ACT ------------------------------------------ 1-3 -5 C. PROJECT HISTORY AND BACKGROUND ----------------------- D. PROJECT OBJECTIVES ----------------------------------- 1-7 E. STUDY AREA AND LAKES --------------------------------- 1-7 II. BACKGROUND ------------------------------------------------- 2-1 2-1 A. LACUSTRINE CONCEPTS ---------------------------------- B. OPTICAL PROPERTIES OF PURE AND NATURAL WATERS -------- 2-5 2-7 C. REMOTE SENSING SYSTEMS ------------------------------- 2-19 D. PERIPHERAL EFFECTS ----------------------------------- 2-25 E. REMOTE SENSING OF COLORADO LAKES --------------------- F. TROPHIC INDICATORS AND A MULTIVARIATE TROPHIC INDEX ---------------------------------------- 2-31 2-36 G. MULTISPECTRAL CLASSIFICATION ------------------------- III. METHODS ---------------------------------------------------- 3-1 A. DATA ACQUISITION ------------------------------------- 3-1 3-2 B. MULTISPECTRAL DATA PREPROCESSING --------------------- 3-8 C. LAKE EXTRACTION METHODS ------------------------------ D. WATER SAMPLE SITE LOCATIONS -------------------------- 3-13 E. PIXEL DENSITY AT SAMPLE SITES ------------------------ 3-13 3-14 F. LAKE SURFACE AREA DETERMINATION ---------------------- G. TROPHIC INDICATOR SELECTION AND MULTIVARIATE INDICES DEVELOPMENT ---------------------------------- 3-17 H. ANALYSES OF TROPHIC INDICATOR, TROPHIC STATE INDEX, 3-21 AND REMOTELY SENSED DATA RELATIONSHIPS --------------- vME i I IV. RESULTS AND DISCUSSION ------- 1 ----------------------------- 4-1 A. LAKE SURFACE AREA ----------------------------------- 4-1 B. PRINCIPAL COMPONENT TROPHIC ORDINATION OF LAKES AND SAMPLING SITES INDICATORS ---------------------------- 4-4 C. CORRELATION AND REGRESSION ANALYSIS RESULTS ---------- 4-18 D. REGRESSION MODELS FOR THE ESTIMATION OF TROPHIC INDICATORS AND MULTIVARIATE TROPHIC INDICATORS -------- 35 E. THEMATIC NAPPING RESULTS -----------------------------­ 43 F. POINTS OF CONCERN ------------------------------------ 4-59 V. CONCLUSIONS AND RECOMMENDATIONS ---------------------------- 5-i A. CONCLUSIONS ------------------------------------------ 5-1 B. RECOMMENDATIONS -------------------------------------- 5-1 VI. GLOSSARY --------------------------------------------------- 6-I REFERENCES ------------------------------------------------------- R-1 APPENDIXES A. PHYSICAL-CHEMICAL DATA FOR THE COLORADO STUDY LAKES ------------------------------------------ A-I B. PHOTOGRAPHIC FLIGHT LOG OF NASA AIRCRAFT COVERAGE OF COLORADO LAKES, AUGUST 25, 1975 ------------------- B-1 C. REGRESSION MODEL PREDICTED, RESIDUAL, AND ASSOCIATED OBSERVED VALUES --------------------------- C-I Figures 1-1. Number of Lakes Sampled by the National Eutrophication Survey -------------------------------- 1-4 1-2. Landsat-1 Coverage of Colorado NES-Sampled Lakes for August 22-24, 1975 ------------------------------- 1-11 1-3. Color Composite Image of Landsat-1 Scene 5126-16474 Showing Several of the Colorado Test Lakes ----------- 1-12 vi 1-4. Color Composite Image of Landsat-1 Scene 5127-16532 Showing Several of the Colorado Test Lakes ----------- 1-13 1-5. Color Composite Image of Landsat-1 Scene 5127-16534 Showing Several of the Colorado Test Lakes ----------- 1-14 2-1. Hypothetical Productivity Growth Curve of a Hydrosere -------------------------------------------- 2-3 2-2. Reflection Characteristics of Filtered and Unfiltered Water Samples from Two Wisconsin Lakes in the Area of Madison -------------------------------------- 2-8 2-10 2-3. The Landsat Space Observatory ------------------------ 2-12 2-4. Landsat-1 Ground Coverage Pattern -------------------- 2-5. Schematic Diagram of the Landsat-1 MSS Scanning Arrangement ------------------------------------------ 2-15 2-16 2-6. Ground Scan Pattern for a Single MSS Detector -------- 2-17 2-7. Generalized Spectral Reflectance Curve --------------- 2-8. Generalized Output of the Landsat MSS in Response Illustrated in to the Spectral Distribution Figure 2-7 ------------------------------------------- 2-17 2-9. Generalized Output of the Aircraft-Borne MMS in Response to the Spectral Distribution Illustrated in Figure 2-10 --------------------------------------- 2-21 2-10. Generalized Spectral Reflectance Curve for a Single Picture Element of a Hypothetical Lake --------------- 2-22 2-11. Some Components and Interactions of Light with a Hypothetical Lake and the Atmosphere ----------------- 2-23 2-12. IR2 Image of Landsat Scene 5126-16474, August 23, 1975 -------------------------------------- 2-26 2-13. IRI Image of Landsat Scene 5126-16474, August 23, 1975 -------------------------------------- 2-27 2-14. Red Image of Landsat Scene 5126-16474, August 23, 1975 -------------------------------------- 2-28 2-15. GRN Image of Landsat Scene 5126-16474, August 23, 1975 -------------------------------------- 2-29 Components 2-16. Geometrical Interpretation of the Principal 2-35 for a Hypothetical Bivariate System ------------------ vii 3-1. Geometric Corrections Typically Applied to Multispectral Scanner Data --------------------------- 3-5 3-2, Aircraft-Acquired MMS Imagery Before Geometric Corrections ------------------------------------------ 3-6 3-3. Aircraft-Acquired MMS Imagery After Geometric Corrections Have Been Made --------------------------- 3-7 3-4. GRN, RED, IRI, and IR2 Images of a Landsat Scene 5127-16532 Subscene ---------------------------------- 3-9 3-5. GRN, RED, IRI, and IR2 Images of a Landsat Scene 5127-16534 Subscene After the Application of the Binary Mask Generated Using the IR2 DN Range of 0-28 as Representing Water --------------------------- 3-10 3-6. Landsat-1 MSS IR2 Concatenation of Nine Colorado Lakes --------------------------------------- 3-11 3-7. MMS Channel 10 Concatenation of Five Colorado Lakes --------------------------------------- 3-12 3-8. Landsat Pixel Size in Relation to the U.S. Standard One-Mile Section ------------------------------------- 3-15 1 4- . Proportion Estimation Diagram ------------------------ 4-4 4-2. Trophic Classification Maps of Five Colorado Lakes Based on Landsat-1 MSS Data and a Multivariate Trophic Index for 13 Sampling Sites (PC1-13) --------- 4-45 4-3. Trophic Classification Maps of Five Colorado Lakes Based on MNS Data and a Multivariate Trophic Index for 13 Sampling Sites (PC1-13) ----------------------- 4-46 4-4. Trophic
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