NAME
swprod - Determination of primary productivity and community
metabolism in streams and lakes using diel oxygen
measurements
ABSTRACT
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.
METHOD
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.
HISTORY
1991 - Printout modified to 80 columns. The plot option was
eliminated. Additional printout added.
1976 - Version J330, ran on IBM 360 or 370.
DATA REQUIREMENTS
Temperature, dissolved oxygen, and conductivity.
OUTPUT OPTIONS
Output consists of computed production and metabolism results and
optional presentation of interpolated data.
SYSTEM REQUIREMENTS
SWPROD is written in Fortran 77 with the following extension: use of
include files.
DOCUMENTATION
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.
REFERENCES
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.
CONTACTS
Operation and Distribution:
U.S. Geological Survey
Hydrologic Analysis Software Support Program
437 National Center
Reston, VA 20192
h2osoft@usgs.gov
Official versions of U.S. Geological Survey water-resources analysis
software are available for electronic retrieval via the World Wide
Web (WWW) at:
http://water.usgs.gov/software/
and via anonymous File Transfer Protocol (FTP) from:
water.usgs.gov (path: /pub/software).
The WWW page and anonymous FTP directory from which the SWPROD
software can be retrieved are, respectively:
http://water.usgs.gov/software/swprod.html
--and--
/pub/software/water_quality/swprod