1. General Model Information

Name: Determination of Primary Productivity and Community Metabolism in Streams and Lakes using Diel Oxygen Measurements

Acronym: SWPROD

Main medium: aquatic
Main subject: biogeochemistry, hydrology
Organization level: ecosystem
Type of model: ordinary differential equations
Main application:
Keywords: water quality,oxygen,net productivity, night respiration, community metabolism,diel series,water temperature,salinity


U.S. Geological Survey
Hydrologic Analysis Software Support Program 437 National Center Reston, VA 20192
email: h2osoft@usgs.gov



The SWPROD program calculates daytime net productivity, night respiration, and total community metabolism from a diel series of dissolved oxygen, temperature, and salinity measurements. An Odum approach is used for the solution of the oxygen-balance equation at a single station in a stream or as a difference between upstream and downstream stations. Net oxygen production and subsequent community metabolism of horizontal lake segments are calculated assuming a one-dimensional model using a finite-difference equation. The results are useful for general aquatic ecosystem characterization and as input to water-quality models for dissolved-oxygen analysis of aquatic environments. SWPROD is a revision of the USGS program J330.


Procedures for defining the diel oxygen relationship utilize dissolved-oxygen measurements to solve the basic oxygen equation. The applicability and accuracy of the procedures are limited by the assumptions. Reaeration is assumed to be constant over the 24-hour period. Advective transport must be absent or the quantity of oxygen so transported must be known. No assumptions concerning daytime respiration are made; therefore, values for gross production are not calculated. Any accrual or loss of water must be known. Turbulence must be low enough to permit observation of nighttime decline in dissolved oxygen. There must be sufficient plant biomass present to provide a daytime increase in oxygen due to photosynthesis.

II. Technical Information

II.1 Executables:

Operating System(s): UNIX download from USGS

II.2 Source-code:

Programming Language(s): FORTRANdownload from USGS

II.3 Manuals:

II.4 Data:

III. Mathematical Information

III.1 Mathematics

III.2 Quantities

III.2.1 Input

Temperature, dissolved oxygen, electric conductivity.

III.2.2 Output

Output consists of computed production and metabolism results and optional presentation of interpolated data.

IV. References

Stephens, D.W., and Jennings, M.E., 1976, Determination of Primary productivity and community metabolism in streams and lakes using diel oxygen measurements: U.S. Geological Survey Computer Contribution, 100 p.
Bella, D.A., 1970, Dissolved oxygen variations in stratified lakes: American Society of Civil Engineers Journal of Sanitary Engineering, v. 96, no. SA-5, p. 1129-1146.
Odum, H.T., 1956, Primary production in flowing waters: Limnology and Oceanography, v. 1, no. 2, p. 102-117.
Slack, K.V., Averett, R.C., Greeson, P.E., and Lipscomb, R.G., 1973, Methods for collection and analysis of aquatic biological and microbiological samples: U.S. Geological Survey Techniques of Water-Resources Investigations, book 5, chap. A4, 165 p.

V. Further information in the World-Wide-Web

SWPROD Home-Page at USGS

VI. Additional remarks

Last review of this document by:
Status of the document:
last modified by Tobias Gabele Wed Aug 21 21:44:51 CEST 2002

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