Fish Production Correlated with Primary Productivity, not the Morphoedaphic Index

1990 ◽  
Vol 47 (10) ◽  
pp. 1929-1936 ◽  
Author(s):  
John A. Downing ◽  
Céline Plante ◽  
Sophie Lalonde
Keyword(s):  
Standing Stock ◽  
Phytoplankton Production ◽  
Phosphorus Concentration ◽  
Regression Equations ◽  
Fish Production ◽  
Oligotrophic Lakes ◽  
Yield Data ◽  
Total Phosphorus Concentration ◽  
Wide Range ◽  
Morphoedaphic Index

Estimates of the biological production of entire lake fish communities were collected from the published literature on lakes covering a wide range of geographic areas and trophic status. Correlation analysis shows that fish production is uncorrected with the morphoedaphic index (p > 0.05) but closely correlated with annual phytoplankton production (r2 = 0.79), mean total phosphorus concentration (r2 = 0.67), and annual average fish standing stock (r2 = 0.67). Empirically derived regression equations are presented and compared with previous models based on catch and yield data. Analysis of these equations suggests that conversion of phytoplankton into fish production is 100 times more efficient in oligotrophic lakes than hyper-eutrophic ones, but that a much lower fraction of fish production can be channeled to sustainable yield in oligotrophic lakes. Sustained yields were frequently as little as 10% of the annual community fish production.

Phosphorus Input and Its Consequences for Phytoplankton Standing Crop and Production in the Experimental Lakes Area and in Similar Lakes

1978 ◽  
Vol 35 (2) ◽  
pp. 190-196 ◽  
Author(s):  
D. W. Schindler ◽  
E. J. Fee ◽  
T. Ruszczynski
Keyword(s):  
Lake Management ◽  
Phosphorus Loading ◽  
Phytoplankton Production ◽  
Phosphorus Concentration ◽  
Nutrient Inputs ◽  
Experimental Lakes Area ◽  
Total Phosphorus Concentration ◽  
Water Renewal ◽  
Rapid Changes ◽  
Shield Lakes

Correlation and regression analyses were used to assess several expressions for phosphorus loading, with and without corrections for water renewal and sedimentation, as predictors of total phosphorus concentration, chlorophyll, phytoplankton volume, and phytoplankton production in the Experimental Lakes Area (ELA) lakes. All expressions tested were good predictors, allowing predictions of the above parameters with 95% confidence intervals of 20–30% of the mean for any loading value. In general, correction for water renewal improved the fit of the expression, but correction for sedimentation did not. When the above strategy was applied to lakes outside ELA but with Shield or Shield-like drainage, good results were also obtained when expressions incorporating water renewal were used. If uncorrected for water renewal, loading was a poor predictor. Correction for sedimentation did not improve the expressions significantly. Correction for rapid changes in phosphorus input did not improve the predictability of equations, indicating that the equilibrium between ELA lakes and new loading conditions occurs very rapidly. Key words: Precambrian Shield lakes, eutrophication, lake management, nutrient inputs

Empirical Prediction of Fish Biomass and Yield

1982 ◽  
Vol 39 (2) ◽  
pp. 257-263 ◽  
Author(s):  
John Mark Hanson ◽  
William C. Leggett
Keyword(s):  
Biomass Yield ◽  
Phosphorus Concentration ◽  
Fish Biomass ◽  
Data Sets ◽  
Dissolved Solids ◽  
Total Phosphorus Concentration ◽  
Data Set ◽  
Fish Yield ◽  
Empirical Prediction ◽  
Morphoedaphic Index

Data taken from the literature were used to develop and compare predictors of fish biomass and yield in lakes. Two new indices, total phosphorus concentration and macrobenthos biomass/mean depth, were the best univariate predictors offish yield (r2 = 0.84 and r2 = 0.48, respectively) and biomass (r2 = 0.75 and r2 = 0.83, respectively) for four different data sets. Both new indices were stronger predictors of fish yield when compared to the morphoedaphic index, total dissolved solids, or mean depth for the same data set. The relatively constant relationship between fish biomass and macrobenthos biomass/mean depth implies a near-constant energy transfer from the benthos to the fish regardless of the number of fish species present.Key words: biomass, yield, fish, macrobenthos, phosphorus, depth, dissolved solids, morphoedaphic index, lakes

Empirical Relationships of Phytomacrofaunal Abundance to Plant Biomass and Macrophyte Bed Characteristics

1988 ◽  
Vol 45 (6) ◽  
pp. 976-984 ◽  
Author(s):  
Hélène Cyr ◽  
John A. Downing
Keyword(s):  
Organic Matter ◽  
Total Phosphorus ◽  
Plant Biomass ◽  
Organic Matter Content ◽  
Matter Content ◽  
Rooting Depth ◽  
Phosphorus Concentration ◽  
Regression Equations ◽  
Lake Area ◽  
Total Phosphorus Concentration

The abundance of phytophilous invertebrates was measured in 13 macrophyte beds and was related, using multiple regression analysis, to the biomass of macrophytes among which the invertebrates were collected, the average plant biomass growing per unit lake area, water and organic matter content of the sediments, total phosphorus concentration in the water, rooting depth of the macrophyte bed, and sampling date. Quantitative analyses are presented for chironomids, cladocerans, cyclopoid copepods, gastropods, water mites (Hydracarina), ostracods, and trichopterans. R2 values for the regression equations ranged from 0.43 to 0.81. The abundance of invertebrates was best related to the biomass of separate plant species, but equations based only on total plant biomass sometimes had equivalent R2 values, in general, the abundance of phytophilous invertebrates was positively related to areal plant biomass, sediment organic matter, and lake trophic status and negatively related to depth. The abundance of phytophilous invertebrates generally rose throughout the sampling season. The sign of the relationship with sediment water content, however, varied among invertebrate taxa. Macrophyte beds with high areal plant biomass, in lakes with high total phosphorus concentration, support the greatest abundance of potential invertebrate food for fish and waterfowl.

Prediction of Chlorophyll a Concentrations in Florida Lakes: Importance of Aquatic Macrophytes

1984 ◽  
Vol 41 (3) ◽  
pp. 497-501 ◽  
Author(s):  
Daniel E. Canfield Jr. ◽  
Jerome V. Shireman ◽  
Douglas E. Colle ◽  
William T. Haller ◽  
Curtis E. Watkins II ◽  
...  
Keyword(s):  
Chlorophyll A ◽  
Aquatic Macrophytes ◽  
Nitrogen Concentration ◽  
Potential Effect ◽  
Phosphorus Concentration ◽  
Secchi Disc ◽  
Total Phosphorus Concentration ◽  
Florida Lakes ◽  
Wide Range ◽  
Using Data

Chlorophyll a concentrations in Lake Pearl, Florida, increased as the percentage of the lake's total volume infested with aquatic macrophytes decreased. Using data from 32 Florida lakes having a wide range of limnological characteristics, we demonstrated that predictions of chlorophyll a concentrations could be improved by including a term for the percentage of the lake's total volume infested with macrophytes in existing nutrient–chlorophyll models. Our best-fit multivariate regression equation was[Formula: see text]where CHLA is the chlorophyll a concentration (milligrams per cubic metre), TN is the total nitrogen concentration (milligrams per cubic metre), TP is the total phosphorus concentration (milligrams per cubic metre), and PVI is the percentage of the lake's total volume infested with macrophytes. By use of this equation, we assessed the potential effect of aquatic macrophytes on chlorophyll yields and Secchi disc transparencies in lakes of different trophic status.

Prediction of Total Phosphorus Concentrations, Chlorophyll a, and Secchi Depths in Natural and Artificial Lakes

1981 ◽  
Vol 38 (4) ◽  
pp. 414-423 ◽  
Author(s):  
Daniel E. Canfield Jr. ◽  
Roger W. Bachmann
Keyword(s):  
Total Phosphorus ◽  
Environmental Protection Agency ◽  
Secchi Depth ◽  
Sedimentation Coefficient ◽  
Phosphorus Loading ◽  
Phosphorus Concentration ◽  
Total Phosphorus Concentration ◽  
Artificial Lakes ◽  
Wide Range ◽  
Using Data

A model for the prediction of total phosphorus was developed and tested using data on 704 nautral and artificial lakes including 626 lakes in the U.S. Environmental Protection Agency (EPA) National Eutrophication Survey. A statistical analysis showed that the best estimate for the sedimentation coefficient (σ) in the Vollenweider equation was[Formula: see text]for artificial lakes where L is the areal phosphorus loading rate (mg∙m−2∙yr−1) and z is the mean depth (m). The model yields unbiased estimates of phosphorus concentrations over a wide range of lake types and has a 95% confidence interval of 31–288% of the calculated total phosphorus concentration. Other models are less precise. Though total phosphorus concentrations can be predicted equally well in natural and artificial lakes, predictions of algal densities and water transparency are less reliable in artificial lakes, as the phosphorus–chlorophyll and chlorophyll–Secchi depth relationships are less precise. This seems to be due to the influence of nonalgal particulate materials.Key words: phosphorus models, eutrophication, lake trophic state

Epiphyton Biomass is Related to Lake Trophic Status, Depth, and Macrophyte Architecture

1991 ◽  
Vol 48 (11) ◽  
pp. 2285-2291 ◽  
Author(s):  
Sophie Lalonde ◽  
John A. Downing
Keyword(s):  
Trophic Status ◽  
Common Species ◽  
Phosphorus Concentration ◽  
Eutrophic Lakes ◽  
Total Phosphorus Concentration ◽  
Algae Biomass ◽  
Tp 39 ◽  
Poor Predictor ◽  
Wide Range ◽  
The Relationship

The relationship between epiphyton biomass and water column total phosphorus concentration (TP) was studied in macrophyte beds in 11 lakes covering a wide range of trophic status (TP = 5.8–72.8 μg∙L−1). Phosphorus concentration was a poor predictor of epiphyton biomass when considered alone. Our data do not agree with previous studies that found that epiphyton biomass increased continuously with TP. Instead, we found a very weak, nonlinear relationship between TP and epiphyton biomass, where epiphyton biomass increased up to TP≈39 μg∙L−1, and decreased at higher TP. Season and sampling depth accounted for significantly more variation in epiphyton biomass than did TP. Epiphyton biomass increased with depth in oligotrophic lakes but decreased with depth in eutrophic lakes. Seven common species of macrophytes of differing architecture developed significantly different epiphyton biomass. Macrophytes with flexible, ribbon-like leaves supported lower epiphyton biomass than species of broad-leaved or whorled architecture. The effect of host type on epiphyton algae biomass was not, however, as great as the influence of environmental variables.

Periphyton biomass and community composition in rivers of different nutrient status

1999 ◽  
Vol 56 (4) ◽  
pp. 560-569 ◽  
Author(s):  
J Chételat ◽  
F R Pick ◽  
A Morin ◽  
P B Hamilton
Keyword(s):  
Community Composition ◽  
Total Phosphorus ◽  
Algal Biomass ◽  
Standing Stock ◽  
Water Velocity ◽  
Nutrient Concentrations ◽  
Phosphorus Concentration ◽  
Overlying Water ◽  
Total Phosphorus Concentration ◽  
Chl A

Epilithic periphyton was investigated in riffle zones of 13 rivers in southern Ontario and western Quebec to describe how algal biomass and community composition vary with nutrient concentration and water velocity during summer. Algal biomass (milligrams chlorophyll a (Chl a) per square metre) was strongly correlated with total phosphorus concentration (r2 = 0.56, p < 0.001) and conductivity (r2 = 0.71, p < 0.001) of the overlying water but unrelated to water velocity over the range of 10-107 cm·s-1. Differences in periphyton Chl a were associated with changes in biomass of Chlorophyta (r2 = 0.51, p = 0.001) and Bacillariophyta (r2 = 0.64, p < 0.001) and were not related to Rhodophyta and Cyanophyta biomass (p > 0.10). The relative proportions of taxonomic divisions varied with total standing stock. Percent Chlorophyta biomass increased with periphyton Chl a and was the largest fraction at moderately eutrophic sites. Rhodophyta contributed the most biomass at sites with the lowest Chl a. Cladophora, Melosira, and Audouinella biomasses were positively correlated with total phosphorus concentration over the range of 6-82 µg·L-1 (r2 = 0.39-0.64, p < 0.005), and these genera were dominant at sites with the highest nutrient concentrations.

Lake Paranoá, Brasília, Brazil: Integrated Management Plan for its Restoration

1992 ◽  
Vol 27 (2) ◽  
pp. 271-286 ◽  
Author(s):  
Sonia Paulino Mattos ◽  
Irene Guimarães Altafin ◽  
Hélio José de Freitas ◽  
Cristine Gobbato Brandão Cavalcanti ◽  
Vera Regina Estuqui Alves
Keyword(s):  
Total Phosphorus ◽  
Drainage Basin ◽  
Integrated Management ◽  
Algal Growth ◽  
Nutrient Content ◽  
Management Plan ◽  
Cylindrospermopsis Raciborskii ◽  
Phosphorus Concentration ◽  
Limiting Factor ◽  
Total Phosphorus Concentration

Abstract Built in 1959, Lake Paranoá, in Brasilia, Brazil, has been undergoing an accelerated process of nutrient enrichment, due to inputs of inadequately treated raw sewage, generated by a population of 600,000 inhabitants. Consequently, it shows high nutrient content (40 µg/L of total phosphorus and 1800 µg/L of total nitrogen), low transparency (0.65 m) and high levels of chlorophyll a (65 µg/L), represented mainly by Cylindrospermopsis raciborskii and sporadic bloom of Microcystis aeruginosa, which is being combatted with copper sulphate. With the absence of seasonality and a vertical distribution which is not very evident, the horizontal pattern assumes great importance in this reservoir, in which five compartments stand out. Based on this segmentation and on the identification of the total phosphorus parameter as the limiting factor for algal growth, mathematical models were developed which demonstrate the need for advanced treatment of all the sewage produced in its drainage basin. With this, it is expected that a process of restoration will be initiated, with a decline in total phosphorus concentration to readings below 25 µg/L. Additional measures are proposed to accelerate this process.

scholarly journals Phytase-Producing Rahnella aquatilis JZ-GX1 Promotes Seed Germination and Growth in Corn (Zea mays L.)

2021 ◽  
Vol 9 (8) ◽  
pp. 1647
Author(s):  
Gui-E Li ◽  
Wei-Liang Kong ◽  
Xiao-Qin Wu ◽  
Shi-Bo Ma
Keyword(s):  
Seed Germination ◽  
Plant Growth ◽  
Biomass Accumulation ◽  
Root Surface ◽  
Phosphorus Concentration ◽  
Maize Seedlings ◽  
Total Phosphorus Concentration ◽  
Rahnella Aquatilis ◽  
Maize Seeds

Phytase plays an important role in crop seed germination and plant growth. In order to fully understand the plant growth-promoting mechanism by Rahnella aquatilis JZ-GX1，the effect of this strain on germination of maize seeds was determined in vitro, and the colonization of maize root by R. aquatilis JZ-GX1 was observed by scanning electron microscope. Different inoculum concentrations and Phytate-related soil properties were applied to investigate the effect of R. aquatilis JZ-GX1 on the growth of maize seedlings. The results showed that R. aquatilis JZ-GX1 could effectively secrete indole acetic acid and had significantly promoted seed germination and root length of maize. A large number of R. aquatilis JZ-GX1 cells colonized on the root surface, root hair and the root interior of maize. When the inoculation concentration was 107 cfu/mL and the insoluble organophosphorus compound phytate existed in the soil, the net photosynthetic rate, chlorophyll content, phytase activity secreted by roots, total phosphorus concentration and biomass accumulation of maize seedlings were the highest. In contrast, no significant effect of inoculation was found when the total P content was low or when inorganic P was sufficient in the soil. R. aquatilis JZ-GX1 promotes the growth of maize directly by secreting IAA and indirectly by secreting phytase. This work provides beneficial information for the development and application of R. aquatilis JZ-GX1 as a microbial fertilizer in the future.

Balance between Phytoplankton Production and Plankton Respiration in Lakes

1993 ◽  
Vol 50 (2) ◽  
pp. 282-289 ◽  
Author(s):  
Paul A. del Giorgio ◽  
Robert H. Peters
Keyword(s):  
Community Respiration ◽  
Phytoplankton Production ◽  
External Energy ◽  
Eutrophic Lakes ◽  
Oligotrophic Lakes ◽  
Plankton Community Respiration ◽  
Algal Photosynthesis ◽  
Chlorophyll Concentrations ◽  
Trophic Range ◽  
Good Agreement

We analyzed published rates of algal photosynthesis and plankton community respiration to test the hypothesis that the ratio of planktonic primary production to community (P/R) varies systematically with lake trophy. Regression analyses show that algal production and plankton respiration are closely related to chlorophyll concentrations for lakes spanning a wide trophic range. More surprisingly, plankton respiration exceeds algal photosynthesis in oligotrophic lakes, and P/R rises above unity only when chlorophyll concentrations are above 17 mg∙m−3. A simple allometric model based on the predicted biomasses of the different planktonic component yield rates of community respiration that are in good agreement with measured values. Moreover, the model suggest that in oligotrophic lakes, microbial respiration may greatly exceed the current estimates based on bacterial production data and that heterotrophs contribute proportionately more to total plankton metabolism than they do in eutrophic lakes. Because such high respiration rates require external energy subsidies, these results; challenge the view that pelagial communities of most lakes are even approximately self-supporting.

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