Abstract
Water quality data from 30 stations of the National Stream Quality Accounting Network (NASQAN) in the Ohio River basin were examined for spatial adequacy. A direct statistical test of differences between two sample means (for small sample size and unknown population variances) found that for over onehalf of the 53 water quality parameters, differences in water quality could not be distinguished for more than one‐third of the station pairs. An indirect statistical approach, correlating mean water quality to 136 possible explanatory basin characteristics, resulted in reasonable cause‐effect relationships for only 23 parameters. Based on a method developed to determine a spatially adequate sample size, it is recommended that the current bimonthly or quarterly sampling frequency be increased to monthly for all parameters and that the current annual reporting period be increased to four years. Other suggestions to make the system more cost‐effective are included.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
