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Lakes and Reservoirs: Guidelines for Study Design and Sampling Lakes and Reservoirs: Guidelines for Study Design and Sampling Chapter 10 of Section A, National Field Manual for the Collection of Water-Quality Data Book 9, Handbooks for Water-Resources Investigations Techniques and Methods 9–A10 Supersedes USGS Techniques of Water-Resources Investigations Book 9, Chapter A10, version 1.0 U.S. Department of the Interior U.S. Geological Survey Cover: Photograph of the Annie, “First Boat Ever Launched on Yellowstone Lake." Reported to first be used on June 29, 1871. James Stevenson and H.W. Elliott, 5th annual report, page 96. William Henry Jackson, photographer (Yellowstone National Park). U.S. Geological and Geographical Survey of the Territories, Yellowstone Series, 1871, Vol. III (Hayden Survey). Image file: http://library.usgs.gov/ photo/#/item/51dca2c7e4b097e4d383aebd. Lakes and Reservoirs: Guidelines for Study Design and Sampling By U.S. Geological Survey Chapter 10 of Section A, National Field Manual for the Collection of Water-Quality Data Book 9, Handbooks for Water-Resources Investigations Techniques and Methods 9–A10 Supersedes USGS Techniques of Water-Resources Investigations, Book 9, Chapter A10, version 1.0 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior RYAN K. ZINKE, Secretary U.S. Geological Survey James F. Reilly II, Director U.S. Geological Survey, Reston, Virginia: First release: 2015, online as Techniques of Water-Resources Investigations, book 9, chapter A10, version 1.0 Revised: May 2018, online as Techniques and Methods, book 9, chapter A10 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit https://www.usgs.gov or call 1–888–ASK–USGS. For an overview of USGS information products, including maps, imagery, and publications, visit https://store.usgs.gov. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Suggested citation: U.S. Geological Survey, 2018, Lakes and reservoirs—Guidelines for study design and sampling: U.S. Geological Survey Techniques and Methods, book 9, chap. A10, 48 p., https://doi.org/10.3133/tm9a10. [Supersedes USGS Techniques of Water-Resources Investigations, book 9, chap. A10, version 1.0] ISSN 2328-7055 (online) iii Contents Abstract ...........................................................................................................................................................1 1.0 Introduction .............................................................................................................................................1 1.1 Purpose and Scope .......................................................................................................................3 2.0 Basic Limnology ......................................................................................................................................3 2.1 Physical and Chemical Limnology ..............................................................................................6 2.1.1 Light and Water Clarity .....................................................................................................7 2.1.2 Temperature and Stratification .......................................................................................8 2.1.3 pH .......................................................................................................................................10 2.1.4 Dissolved Oxygen ............................................................................................................10 2.1.5 Phosphorus and Nitrogen ..............................................................................................11 2.1.6 Chlorophyll a .....................................................................................................................11 2.2 Trophic Classification ..................................................................................................................12 2.3 Biological Limnology ..................................................................................................................13 2.3.1 Littoral Zone ......................................................................................................................13 2.3.2 Pelagic Zone .....................................................................................................................14 2.3.3 Profundal Zone .................................................................................................................14 3.0 Comparative Properties of Lakes and Reservoirs ..........................................................................14 3.1 Spatial and Temporal Heterogeneity .......................................................................................15 3.2 Reservoir Aging............................................................................................................................17 4.0 General Considerations for Study Design ........................................................................................18 4.1 Common Study Types ..................................................................................................................19 4.1.1 Reconnaissance Studies ................................................................................................21 4.1.2 Diagnostic Studies ..........................................................................................................22 4.1.3 Interpretive Studies .........................................................................................................22 4.2 Sampling Strategies and Approaches .....................................................................................23 4.2.1 What to Sample ...............................................................................................................23 4.2.2 How Many Samples to Collect ......................................................................................24 4.2.3 Where to Sample: Systematic, Random, and Stratified Approaches ....................25 4.2.4 When to Sample: Seasonal and Diurnal Considerations .........................................25 5.0 Preparations for Data Collection: Data Management and Safety Precautions .........................26 5.1 Site Files ........................................................................................................................................27 5.2 Safety Precautions ......................................................................................................................27 6.0 Field-Measured Properties .................................................................................................................29 6.1 Light Attenuation .........................................................................................................................31 6.2 Multiparameter Instrument Sondes .........................................................................................31 6.2.1 Temperature, Dissolved Oxygen, pH, Specific Electrical Conductance, and Turbidity ..........................................................................................................................31 6.2.2 Algal Biomass: Photosynthetic Pigments ...................................................................32 6.2.3 Ultraviolet Nitrate Sensors ...........................................................................................32 iv 6.3 Methods of Sonde Deployment .................................................................................................32 6.3.1 Profiling .............................................................................................................................32 6.3.2 Water-Quality Monitoring Platforms with Continuous Sensors or Multiparameter Sondes ..............................................................................................33 7.0 Sampling in the Water Column ...........................................................................................................35 8.0 Sampling Bottom Material ..................................................................................................................36 9.0 Sampling Biological Components ......................................................................................................36 9.1 Phytoplankton...............................................................................................................................37 9.1.1 Sample Collection ............................................................................................................37 9.1.2 Ancillary Data ...................................................................................................................37 9.2 Zooplankton ..................................................................................................................................38 9.2.1 Sample Collection ............................................................................................................38 9.2.2 Ancillary Data ..................................................................................................................38 9.3 Microorganisms ...........................................................................................................................38
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