|
<br />DESCRIPTION OF DATA-SET DISKETTE
<br />
<br />The MSDOS format 3.5-in. diskette inside the
<br />back cover pocket contains the compiled nutrient and
<br />ancillary data set in an ASCII text file named uco1.txt.
<br />The diskette contains 76 tab-delimited parameter
<br />fields, including remark fields, for the 49 parameters
<br />listed in table 1. The data are arranged as one line per
<br />unique sample date and time for each site. The data set
<br />is sorted sequentially by map reference number, date,
<br />and time.
<br />The first line of the file contains the parameter
<br />field names in the same order as listed in table 1. The
<br />second line of the file defines the type (n = numeric,
<br />s = character string, d = date) and width of each
<br />parameter field. Data values begin on line 3 of
<br />uco1.txt. Water-quality constituents that have a labora-
<br />tory reporting limit have a separate character field for
<br />remark (data censoring) codes. These remark fields are
<br />positioned to the left of their associated constituent.
<br />All remark fields have the same name as their associ-
<br />ated constituent, except the first letter of the remark
<br />field is an "r." For example, the remark fields for the
<br />nitrate and pOO600 parameter fields are mitrate and
<br />r00600, respectively. Constituent concentrations
<br />reported as above or below a laboratory reporting
<br />limit or undetected are considered censored values
<br />and have a">," "<," or ""0" in their remark field. A
<br />">" in the remark field indicates that the actual value
<br />is known to be greater than the value in the parameter
<br />field for that constituent. A "<" in the remark field
<br />indicates the actual value is known to be less than
<br />the value in the parameter field for that constituent,
<br />whereas a "U" in the remark field indicates the
<br />material was specifically analyzed for, but was
<br />undetected (Maddy and others, 1990, p. 2-14). There
<br />are several methods for determining the concentration
<br />of a given constituent in water; therefore, several
<br />different laboratory reporting limits may be present
<br />for a single constituent.
<br />To load the data set into a spread sheet or other
<br />software package, insert the file as ASCII text, tab-
<br />delimited data. For best results, if possible, be sure to
<br />
<br />import the parameter field for the site identification
<br />number (staid, table 1) as character text to preserve the
<br />leading zeros for site identification numbers.
<br />An ASCII text version of table 1 is included on
<br />the data diskette. The file is named table 1.txt and is
<br />provided so table 1 can be printed out and easily
<br />referenced while working with the nutrient data set.
<br />The data set also is available for retrieval on
<br />the World Wide Web at: http://webserver.cr.usgs.gov/
<br />nawqa/ucol/ucoLhome.html
<br />
<br />REFERENCES CITED
<br />
<br />Apodaca, L.E., Driver, N.E., Stephens, V.C., and Spahr,
<br />N .E., 1996, Environmental setting and implications on
<br />water quality, Upper Colorado River Basin, Colorado
<br />and Utah: U.S. Geological Survey Water-Resources
<br />Investigations Report 95-4263, 33 p.
<br />Bureau of Census, 1990, 1992, census of population and
<br />housing: Washington, D.C., U.S. Department of
<br />Commerce, data on CD-ROM.
<br />Driver, N.E., 1994, National Water-Quality Assessment
<br />Program-Upper Colorado River Basin: U.S. Geolog-
<br />ical Survey Open-File Report 94-102,2 p. [Water
<br />fact sheet.]
<br />Maddy, D.V., Lopp, L.E., Jackson, D.L., Coupe, R.H.,
<br />and Schertz, T.L., 1990, National Water Information
<br />System user's manual-v. 2, chap. 2, Water-
<br />quality system: U.S. Geological Survey Open-File
<br />Report 89--617, 222 p.
<br />Mueller, D.K., Hamilton, P.A., Helsel, D.R., Hitt, K.J.,
<br />and Ruddy, B.C., 1995, Nutrients in ground water
<br />and surface water of the United State!r-An analysis
<br />of data through 1992: U.S. Geological Survey Water-
<br />Resources Investigations Report 95-4031,74 p.
<br />Spahr, N.E., Driver, N.E., and Stephens, V.C., 1996,
<br />The Upper Colorado River Basin National Water-
<br />Quality Assessment Program surface-water-
<br />monitoring network: U.S. Geological Survey Fact
<br />Sheet FS-191-96, 4 p. [Water fact sheet.]
<br />Spahr, N.E., and Wynn, K.H., 1997, Nitrogen and
<br />phosphorus in surface waters of the Upper Colorado
<br />River Basin: Journal of the American Water Resources
<br />Association, v. 33, no. 3, p. 547-560.
<br />
<br />14 Nitrogen and Phosphorus Data for Surface Water In the Upper Colorado River Basin, Colorado, 198O-B4
<br />
|