caa a22 4500 445893257 CHVBK 20180317145623.0 cr unu---uuuuu 170323e20111001xx s 000 0 eng 10.1007/s10750-011-0817-y doi (NATIONALLICENCE)springer-10.1007/s10750-011-0817-y The evaluation of a rake method to quantify submersed vegetation in the Upper Mississippi River [Elektronische Daten] [Yao Yin, Rebecca Kreiling] A long-handled, double-headed garden rake was used to collect submersed aquatic vegetation (SAV) and compared to in-boat visual inspection to record species presence at 67 individual sites. Six rake subsamples were taken at each site and a rake density rating was given to each species collected in the subsamples. Presence at the site, frequency of occurrence in the six rake samples, and additive density rating (the sum of the six rake density ratings) were quantified for each species at each site. The validity of the indices was tested against biomass data collected by clipping all remaining vegetation from the 67 sites. In the turbid water of the Mississippi River, visual inspection of SAV from boats was ineffective with only 27% of the species detected, while raking retrieved on average 70% of the total number of submersed species in the 67 sites. Presence of species at individual sites was correlated with biomass from Stuckenia pectinata, while frequency of occurrence and additive density rating were correlated with biomass for species with greater than 21g of total biomass from all sites. The efficiency of the rake to collect biomass varied among species; only 18% of total biomass was captured via raking the site six times. Additive density rating as an index of abundance can be used to detect temporal changes in the same water body; however, cross-species comparison is not encouraged unless the efficiency of the rake has been determined for each species being compared. Springer Science+Business Media B.V. (outside the USA), 2011 Abundance nationallicence Biomass nationallicence Mississippi River nationallicence Rake method nationallicence Sampling technique nationallicence Submersed aquatic vegetation nationallicence Yin Yao Upper Midwest Environmental Sciences Center, U.S. Geological Survey, 2630 Fanta Reed Road, 54603, La Crosse, WI, USA aut Kreiling Rebecca Upper Midwest Environmental Sciences Center, U.S. Geological Survey, 2630 Fanta Reed Road, 54603, La Crosse, WI, USA aut Hydrobiologia Springer Netherlands 675/1(2011-10-01), 187-195 0018-8158 675:1<187 2011 675 10750 https://doi.org/10.1007/s10750-011-0817-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10750-011-0817-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Yin Yao Upper Midwest Environmental Sciences Center, U.S. Geological Survey, 2630 Fanta Reed Road, 54603, La Crosse, WI, USA aut NATIONALLICENCE 700 1- Kreiling Rebecca Upper Midwest Environmental Sciences Center, U.S. Geological Survey, 2630 Fanta Reed Road, 54603, La Crosse, WI, USA aut NATIONALLICENCE 773 0- Hydrobiologia Springer Netherlands 675/1(2011-10-01), 187-195 0018-8158 675:1<187 2011 675 10750 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer