caa a22 4500 467904642 CHVBK 20180406152830.0 cr unu---uuuuu 170328e20060401xx s 000 0 eng 10.1007/s10661-006-6555-3 doi (NATIONALLICENCE)springer-10.1007/s10661-006-6555-3 Assessing Water Clarity as a Component of Water Quality in Gulf of Mexico Estuaries [Elektronische Daten] [Lisa Smith, Virginia Engle, J. Summers] The U.S. Environmental Protection Agency Environmental Monitoring and Assessment Program (EMAP) uses water clarity as a water quality indicator for integrated assessments of coastal waters. After the publication of the first National Coastal Condition Report (USEPA, 2001c), the national water clarity reference value of 10% of ambient surface light at 1~m depth was reevaluated and modified to reflect expected differences in regional reference light conditions. These regional differences range from naturally turbid estuaries like those found in Mississippi and Louisiana to clear water estuaries expected to support extensive beds of submerged aquatic vegetation in, e.g., Florida and Tampa Bays. For the second National Coastal Condition Report, water clarity was assessed based on regional reference values (USEPA, 2004). Different regional water clarity reference values and data collection methods necessitated the development of a water clarity index based on light attenuation coefficients (k). This index incorporates regional reference conditions and is interchangeable with secchi depth and percent light transmission calculated from light meter measurements. Evaluation of the water clarity index shows that k values based on transmissivity at 1~m can be estimated from secchi depth measurements and successfully used as a surrogate for transmissivity calculated from light meter data. An approach for assessing water clarity in Gulf of Mexico estuaries using light meter data and secchi depth is presented. Springer Science + Business Media, Inc., 2006 EMAP nationallicence light attenuation coefficient nationallicence percent light transmission nationallicence secchi nationallicence water clarity nationallicence Smith Lisa USEPA Gulf Ecology Division, 1 Sabine Island Drive, Gulf Breeze, Florida, USA aut Engle Virginia USEPA Gulf Ecology Division, 1 Sabine Island Drive, Gulf Breeze, Florida, USA aut Summers J. USEPA Gulf Ecology Division, 1 Sabine Island Drive, Gulf Breeze, Florida, USA aut Environmental Monitoring and Assessment Kluwer Academic Publishers 115/1-3(2006-04-01), 291-305 0167-6369 115:1-3<291 2006 115 10661 https://doi.org/10.1007/s10661-006-6555-3 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10661-006-6555-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Smith Lisa USEPA Gulf Ecology Division, 1 Sabine Island Drive, Gulf Breeze, Florida, USA aut NATIONALLICENCE 700 1- Engle Virginia USEPA Gulf Ecology Division, 1 Sabine Island Drive, Gulf Breeze, Florida, USA aut NATIONALLICENCE 700 1- Summers J. USEPA Gulf Ecology Division, 1 Sabine Island Drive, Gulf Breeze, Florida, USA aut NATIONALLICENCE 773 0- Environmental Monitoring and Assessment Kluwer Academic Publishers 115/1-3(2006-04-01), 291-305 0167-6369 115:1-3<291 2006 115 10661 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer