I. Morphology of Lakes
    A. Bathymetric maps

            contour lines = isobaths (iso-equal; bathy-depth)

            surveying and sonar

    B. Morphometry
       Size parameters
        1. Maximum depth = zm
        2. Maximum length = l
        3. Maximum width = b
                at right angles to the maximum length line
        4. Area
                A0 - surface area
                Az - area of contour at depth z
        5. Volume
                V = volume of the whole lake
                Vz = volume below depth z
       Shape parameters
        6. Mean depth average depth symbol
        7. Relative depth
                ratio of maximum depth (z) to the mean diameter of the lake at the surface, expressed as a percentage

        8. Shoreline development.
                L = length of shore line

                DL = shoreline development
        Other useful morphometric tools

        9. Hypsographic curve
                area at each depth – m2 or %
                can use to calculate the volume

        10. Depth-Volume curve
                volume at each depth – m3 or %
                sediment water interactions

II. Lake and Stream  Zonation  -- See page 132 of Wetzel
     A. Lakes
        1. Epilittoral -
        2. Supralittoral -
        3. Littoral - extends from the seasonal high water level down to where the vegetation doesn't grow due to a lack of light
             upper littoral
             middle littoral
             lower littoral 

        4. Littoral-Profundal - no higher plants (can be algae)
        5. Profundal - sediment free of vegetation; low light
        6. Pelagic - open water
            a. trophogenic (euphotic) - enough light for production > respiration
            b. tropholytic - darker – respiration > production
     B. Streams
        1. Eucrenon - the origin of the stream
        2. Hypocrenon
        3. Rithron - stony stream zone
        4. Potamon - lower energy part of the stream - river
        5. Riparian zone
        5. Drainage classification
             stream orders

   C. Biological groups associated with zones (lakes only)
        1. Pelagic
            a. Seston - all particulate matter in the open water
                (1) bioseston -- the living component
                (2) tripton -- non living seston = detritus
            b. Nekton - can swim against currents
            c. Plankton - movement influenced by turbulence
                (1) euplankton - spend whole life cycle in open water
                    (a) bacterioplankton
                    (b) phytoplankton

                    (c) zooplankton
                (2) meroplankton - periodically enter the plankton, but can't spend their whole life cycle there
                (3) pseudoplankton - organisms that don't really live in pelagic, but are swept there accidentally
          2. Benthos - organisms that live on the sediment water interface
            a. Phytobenthos - 'macrophytes' higher plants; algae
            b. Zoobenthos
          3. Other
            a. Pleuston - at the air-water interface
            b. Neuston - microscopic pleuston
            c. Periphyton - plants (and bacteria) that live on the substrates
                (1) epiphytic
                (2) epipelic
                (3) epilithic
                (4) epipsammic
            d. Psammon - interstitial fauna -- they live between sediment grains

Interested in lake morphometry and its effect on lake properties?  Some additional references are:


Håkanson, L. 2004. Lakes: Form and Function. The Blackburn Press, Caldwell, N.J. 201 pp.


Fee, E.J. 1979. A relation between lake morphometry and primary productivity and its use in interpreting whole-lake eutrophication experiments. Limnol. Oceanogr. 24(3): 401-416.

Hondzo, M. and H.G. Stefan. 2006. Dependence of water quality and fish habitat on lake morphometry and meteorology. J. Water Resour. Plng. And Mgmt. 122(5): 364-373.

Rasmussen, J.B., L. Godbout, and M. Schallenberg. 1989. The humic content of lake water and its relationship to watershed and lake morphometry. Limnol. Oceanogr. 34(7): 1336-1343.

Sterner, R.W. 1990. Lake morphometry and light in the surface layer. Can. J. Fish. Aquat. Sci. 47(4): 687-692.


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