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
A hierarchical approach to assessing habitat suitability and yield potential of lake trout
TL;DR: It is determined that the lake is capable of supporting a self-sustaining lake trout population, with surplus production available for a fishery, prior to any consideration of yield potential, and the steps required to perform this assessment and determine yield expectations are outlined.
Journal ArticleDOI
Local nutrient regimes determine site-specific environmental triggers of cyanobacterial and microcystin variability in urban lakes
TL;DR: This study investigates the site-specificity of environmental triggers for cyanobac- terial bloom and microcystin dynamics in three urban lakes in Western Australia and suggests that identification of significant envi- ronmental factors under site- specific conditions is an impor- tant strategy to enhance successful outcomes in cyanobacte- rial bloom control measures.
Journal ArticleDOI
Applicability of Littoral Food-web Biomanipulation for Lake Management Purposes: Snails, Macrophytes, and Water Transparency in Northeast Ohio Shallow Lakes
TL;DR: The results suggest that littoral food-web biomanipulation may be employed as a management technique in some cases after conditions are brought above a “threshold” for plant growth.
Journal ArticleDOI
Spatial distribution, bioavailability, and toxicity of metals in surface sediments of tropical reservoirs, Brazil
Daniele Frascareli,Sheila Cardoso-Silva,Juliana de Oliveira Soares Silva Mizael,André Henrique Rosa,Marcelo Luiz Martins Pompêo,Julio C. López-Doval,Viviane Moschini-Carlos +6 more
TL;DR: Principal component analysis indicated greater influence of metals in the Barra Bonita, Salto Grande, and Rio Grande reservoirs, corroborating the PLI, EF, and BG data.
Journal ArticleDOI
Relationship between space distribution of the benthic macroinvertebrates community and trophic state in a Neotropical reservoir (Itupararanga, Brazil)
Frederico Guilherme de Souza Beghelli,André Cordeiro Alves dos Santos,Maria Virginia Urso-Guimarães,Maria do Carmo Calijuri +3 more
TL;DR: In this paper, the authors verify the benthic macroinvertebrates community responses through environmental factors along a headwater tropical reservoir using a Van-Veen grab along the reservoir in littoral and profundal regions.
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.