Journal ArticleDOI
A trophic state index for lakes1
TLDR
A numerical trophic state index for lakes has been developed that incorporates most lakes in a scale of 0 to 100, which represents a doubling in algal biomass as well as various measures of biomass or production.Abstract:
A numerical trophic state index for lakes has been developed that incorporates most lakes in a scale of 0 to 100. Each major division ( 10, 20, 30, etc. ) represents a doubling in algal biomass. The index number can bc calculated from any of several parameters, including Secchi disk transparency, chlorophyll, and total phosphorus. My purpose here is to present a new approach to the trophic classification of lakes. This new approach was developed because of frustration in communicating to the public both the current nature or status of lakes and their future condition after restoration when the traditional trophic classification system is used. The system presented hcrc, termed a trophic state index (TSI), involves new methods both of defining trophic status and of determining that status in lakes. All trophic classification is based on the division of the trophic continuum, howcvcr this is defined, into a series of classes termed trophic states. Traditional systems divide the continuum into three classes: oligotrophic, mesotrophic, and cutrophic. There is often no clear delineation of these divisions. Determinations of trophic state are made from examination of several diverse criteria, such as shape of the oxygen curve, species composition of the bottom fauna or of the phytoplankton, conccntrations of nutrients, and various measures of biomass or production. Although each changes from oligotrophy to eutrophy, the changes do not occur at sharply defined places, nor do they all occur at the same place or at the same rate. Some lakes may be considered oligotrophic by one criterion and eutrophic by another; this problem isread more
Citations
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Journal ArticleDOI
Lake Ecosystem Energetics: The Missing Management Link
Robert W. Kortmann,Peter H. Rich +1 more
TL;DR: An understanding of the nitrogen, sulfur, iron, and phosphorus cycles of lakes yields insight into new restoration technologies and how these ecosystem components and processes can be effectively managed.
Journal ArticleDOI
Effect of eutrophication and humification on nutrient cycles and transfer efficiency of matter in freshwater food webs
Maciej Karpowicz,Piotr Zieliński,Magdalena Grabowska,Jolanta Ejsmont-Karabin,Joanna Kozłowska,Irina Feniova +5 more
TL;DR: In this article, the authors evaluated how eutrophication and humification impacted nutrient cycles and the efficiency of carbon transfer in the planktonic food webs of 12 lakes in north-eastern Poland that differed in trophic state.
Journal ArticleDOI
Detection and quantification of major toxigenic Microcystis genotypes in Moo-Tan reservoir and associated water treatment plant
TL;DR: DGGE bands clearly demonstrated the presence of potential microcystin producers in both water treatment plants and finished water samples, and it was demonstrated that toxigenic Microcystis sp.
Species richness and distribution of oligochaetes in six reservoirs on Middle and Low Tietê River (SP, Brazil).
TL;DR: The structure of the Oligochaeta populations in six reservoirs located in the Middle and Low section of Tiete River was determined and a gradient was observed in the number of species per reservoir, which diminished steadily from Barra Bonita to Tres Irmaos dam.
Journal ArticleDOI
Evaluating the feasibility of using Sentinel-2 imagery for water clarity assessment in a reservoir
Matias Bonansea,Matias Bonansea,Micaela Ledesma,Raquel Bazán,Anabella Ferral,Alba German,Patricia O'Mill,Claudia Rodriguez,Lucio P. Pinotti +8 more
TL;DR: In this article, the suitability of Sentinel-2 imagery for estimating and mapping Secchi disk transparency (SDT) in Rio Tercero reservoir (Cordoba-Argentina) was evaluated.
References
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Journal ArticleDOI
The phosphorus‐chlorophyll relationship in lakes1,2
P. J. Dillon,F. H. Rigler +1 more
TL;DR: In this article, data for summer chlorophyll and spring total phosphorus concentration were collected from 19 lakes in southern Ontario and combined with data reported in the literature for other North American lakes to produce a regression line that can be used to predict the average summer CHP from a single measurement of phosphorus concentration at spring overturn.
Journal ArticleDOI
Environmental control of photosynthesis in the sea
TL;DR: In this article, a theoretical equation for the photosynthesis-light relation is developed which includes the effects of inhibition in intense light, assuming that phytoplankton adapts to seasonal light changes and that nutrient deficiency affects the carbon:chlorophyll ratio of natural phyto-ankton populations.
Journal Article
Primary production by phytoplankton community in some Japanese lakes and its dependence on lake depth
Journal ArticleDOI
Phosphorus, Nitrogen, and Algae in Lake Washington after Diversion of Sewage
TL;DR: After diversion of sewage effluent from Lake Washington, winter concentrations of phosphate and nitrate decreased at different rates, but nitrate remained at more than 80 percent of the 1963 value and free carbon dioxide and alkalinity remained relatively high.