Experimental Manipulation of Algal Bloom Composition by Nitrogen Addition

1980 ◽  
Vol 37 (7) ◽  
pp. 1175-1183 ◽  
Author(s):  
J. Barica ◽  
H. Kling ◽  
J. Gibson
Keyword(s):  
Species Composition ◽  
Algal Blooms ◽  
Algal Bloom ◽  
Nitrogen Addition ◽  
Oxygen Depletion ◽  
Experimental Manipulation ◽  
Fish Kill ◽  
Fish Kills ◽  
Total Absence ◽  
Prairie Lakes

Nitrogen (as ammonium, nitrate, or both) was added over an 8- to 12-wk period to enclosures in a small prairie lake and to a whole pond. In previous years, both had experienced seasonal anoxia as a result of collapses of Aphanizomenon flos-aquae blooms followed by a massive fish kill. Additions altered the bloom magnitude and the species composition if N was added prior to the appearance of A. flos-aquae. Low additions (~ 0.75–1.5 g m−8∙wk−1) initiated after the appearance of the cyanophyte bloom resulted in a significant reduction of the A. flos-aquae biomass, while the same addition at the time of a chlorophyte bloom (Scenedesmus and Oocystis sp.) caused a substantial shift to Microcystis aeruginosa. High additions (~ 7–14 g m−3∙wk−1) resulted in a total absence of cyanophytes and were followed by a complete shift to small chlorophytes and cryptomonads, with a total absence of A. flos-aquae and the fish kill. Low additions of N did not show any accumulation over 3–5 mo after discontinuation of the fertilization; high additions showed a significant accumulation of nitrate in the water. Both lake and pond returned to heavy A. flos-aquae blooms and fish kills the following summer when not fertilized.Key words: nutrient enrichment, nitrogen, algal blooms, fish kills, oxygen depletion, prairie lakes, biomanipulation, eutrophication

Summerkill Risk in Prairie Ponds and Possibilities of its Prediction

1975 ◽  
Vol 32 (8) ◽  
pp. 1283-1288 ◽  
Author(s):  
Jan Barica
Keyword(s):  
Chlorophyll A ◽  
Algal Blooms ◽  
Oxygen Depletion ◽  
Ammonia Nitrogen ◽  
Specific Conductance ◽  
Rating System ◽  
Late Winter ◽  
Fish Kills ◽  
Secchi Disc ◽  
Prediction Systems

Summer fish kills in shallow, landlocked ponds of the Erickson–Elphinstone area, southwestern Manitoba, were caused by collapses of heavy algal blooms, mostly Alphanizomenon flos-aquae, and subsequent oxygen depletion. Kills occurred only in ponds that were in the specific conductance range of 800–2000 μmho/cm and where chlorophyll a concentrations exceeded 100 μg/liter. A practical rating system for assessment of summerkill risk was suggested. Correlations between various parameters from 51 ponds were computed; the best correlation (r = 0.866; P = >0.99) was found between the late-winter concentration of ammonia nitrogen and the maximum concentration of chlorophyll a in the following summer. Two summerkill prediction systems were proposed, based on ammonia, dissolved oxygen, and Secchi disc transparency, enabling the prediction of summerkill risk 9 or 3 mo prior to stocking of the fish.

Oxygen Depletion and Winterkill Risk in Small Prairie Lakes Under Extended Ice Cover

1979 ◽  
Vol 36 (8) ◽  
pp. 980-986 ◽  
Author(s):  
Jan Barica ◽  
John A. Mathias
Keyword(s):  
Dissolved Oxygen ◽  
Average Rate ◽  
Oxygen Depletion ◽  
Oxygen Storage ◽  
Lake Depth ◽  
Fish Kill ◽  
Initial Oxygen ◽  
Storage Rate ◽  
Prairie Lakes ◽  
The Mean

Mean rates of dissolved oxygen depletion in 10 shallow eutrophic prairie lakes (area 2.3–27.3 ha, mean depth 1.6–4.2 m), ranged from 0.22 to 0.34 g/m2∙d−1 for nonstratified lakes and 0.32–0.42 g/m2∙d−1 for stratified ones. An average rate for all lakes was 0.29 ± 0.06 g/m2∙d−1. The rates correlated with the lake depth. A method for estimating the winterkill risk on the basis of initial oxygen storage, rate of dissolved oxygen depletion and/or the mean or maximum lake depth is proposed. Key words: prairie lakes, oxygen depletion rates, winter fish kill, eutrophication, metabolism, oxygen storage

scholarly journals Phosphorous runoff risk assessment and its potential management using wollastonite according to geochemical modeling

2019 ◽  
Vol 4 (1) ◽  
pp. 787-794 ◽  
Author(s):  
Aneela Hayder ◽  
Stephen Vanderburgt ◽  
Rafael M. Santos ◽  
Yi Wai Chiang
Keyword(s):  
Risk Analysis ◽  
Algal Blooms ◽  
Agricultural Land ◽  
Algal Bloom ◽  
Risk Mitigation ◽  
Geochemical Modeling ◽  
Geochemical Modelling ◽  
Water Runoff ◽  
Phosphorus Pollution ◽  
Contaminate Drinking Water

AbstractLoss of phosphorus from agricultural land through water runoff causes serious detrimental effects on the environment and on water quality. Phosphorous runoff from excessive use of fertilizers can cause algal blooms to grow in nearby water systems, producing toxins that contaminate drinking water sources and recreational water. In this study, a risk analysis of the algal toxin micro-cystin-LR and the mitigation of phosphorus from agriculture runoff is discussed. A risk analysis was performed on the algal bloom toxin microcystin-LR considering the Lake Erie algal bloom event of 2011 as a case study. Toxicity risk analysis results show that relatively low concentrations of microcystin-LR compared to recent case studies pose an acute health risk to both children and adults, and a significant increase in the risk of developing cancer is suggested but subject to further study given the assumptions made. This study investigated the potential of using wollastonite to mitigate phosphorus pollution, considering thermodynamic conditions of a constructed wetland receiving influent water from agriculture runoff, by using geochemical modelling. Geochemical modelling results show that wollastonite can react with phosphorus and capture it in the stable mineral form of hydroxyapatite, offering a possible strategy for risk mitigation of phosphorous runoff. A removal efficiency of 77% of phosphorus using wollastonite is calculated with the help of geochemical modelling.

scholarly journals Interaction between simulated dense Scenedesmus dimorphus (Chlorophyta) bloom and freshwater meta-zooplankton community

2018 ◽  
Vol 77 (2) ◽  
Author(s):  
Zengling Ma ◽  
Hengguo Yu ◽  
Ronald Thring ◽  
Chuanjun Dai ◽  
Anglv Shen ◽  
...  
Keyword(s):  
Community Structure ◽  
Green Algae ◽  
Aquatic Ecosystems ◽  
Algal Blooms ◽  
Algal Bloom ◽  
Photochemical Efficiency ◽  
Zooplankton Community ◽  
Post Inoculation ◽  
Zooplankton Community Structure ◽  
Scenedesmus Dimorphus

Algal bloom has been a subject of much research, especially the occurrence of blue-green algae (cyanobacteria) blooms and their effects on aquatic ecosystems. However, the interaction between green algae blooms and zooplankton community was rarely investigated. In the present study, the effects exerted by Scenedesmus dimorphus (green alga) bloom on the community structure of zooplankton and the top-down control of the bloom process mediated by the zooplankton were evaluated using a series of laboratory cultures. The results showed that a dense S. dimorphus bloom could change the zooplankton community structure by decreasing its diversity indices, leading to the enrichment of a particular zooplankton species, Brachionus calyciflorus. In the presence of mixed species of zooplankton, the density of S. dimorphus in the culture was decreased as determined by a change in total chlorophyll a (Chl a) concentration, which was about 200 μg L-1 lower than that of the zooplankton-free culture. Furthermore, the number of species belonging to Cladocera, Copepoda and Rotifera all decreased, with all the cladocerans disappeared in the co-culture within 2 weeks of culturing, while the density of rotifers increased from 818 (±243) ind L-1 at the time of inoculation to 40733 (±2173) ind L-1 on the 14th day post-inoculation. Grazing of S. dimorphus by the rotifer B. calyciflorus neutralized its growth, and the gradual increase in B. calyciflorus density eventually led to the collapse of the bloom. Furthermore, grazing by B. calyciflorus also led to a decrease in the maximal photochemical efficiency (Fv/Fm) of photosystem II (PSII). The combined changes occurring in the zooplankton community structure during the process of S. dimorphus bloom and the negative effects of grazing on algal growth, morphology and photosynthetic activities confirmed the key role of zooplankton in the control of algal bloom. The results of the study therefore indicated that dense algal blooms caused by non-toxic algae could still remain a threat to aquatic ecosystems.

Relationship Between Thermal Stability and Summer Oxygen Depletion in a Prairie Pothole Lake

1980 ◽  
Vol 37 (9) ◽  
pp. 1433-1438 ◽  
Author(s):  
M. H. Papst ◽  
J. A. Mathias ◽  
J. Barica
Keyword(s):  
Thermal Stability ◽  
Air Temperature ◽  
Algal Biomass ◽  
Thermal Instability ◽  
Oxygen Depletion ◽  
Prairie Pothole ◽  
Night Time ◽  
Algae Blooms ◽  
Principal Factors ◽  
Prairie Lakes

Periods of summer oxygen depletion (summerkill), occurring in shallow prairie lakes, are dependent on the collapse of algae blooms but are not an obligatory result of the collapse. A period of thermal instability following this bloom collapse, or coincidental with it, is a necessary requirement. Wind stress and night-time air temperature are the principal factors determining the degree of thermal stability. These findings explain the speed with which oxygen depletion can occur, that the occurrence of algal biomass collapses without severe oxygen depletion (partial collapses), and the correlation between the occurrence of periods of lake oxygen depletion and changing weather conditions.Key words: lake, summerkill, anoxia, mixing, oxygen depletion, thermal stability, weather, Aphanizomenon

scholarly journals The Ocean’s Elevator: Evolution of the Air-Seawater Interface During a Small-Scale Algal Bloom

2020 ◽  
Author(s):  
Mickey Rogers ◽  
Jennifer Neal ◽  
Ankur Saha ◽  
Abdullah Algarni ◽  
Thomas Hill ◽  
...  
Keyword(s):  
Algal Blooms ◽  
Structural Changes ◽  
Organic Molecules ◽  
Algal Bloom ◽  
Small Scale ◽  
Surface Imaging ◽  
Brewster Angle Microscopy ◽  
Surface Active ◽  
Marine Algal ◽  
Late Stages

We explore in situ the surface properties of marine algal blooms of diatom monocultures by utilizing surface techniques of Brewster angle microscopy (BAM) imaging, vibrational sum frequency generation spectroscopy (SFG), and infrared reflection absorption spectroscopy (IRRAS). Over the course of the bloom, the marine algae produce surface-active biogenic molecules that temporally partition to the topmost interfacial layers and are selectively probed through surface imaging and spectroscopic measurements. BAM images show morphological structural changes and heterogeneity in the interfacial films with increasing density of surface-active biogenic molecules. Film thickness calculations quantified the average surface thickness over time. The image results reveal an ~5 nm thick surface region in the late stages of the bloom which correlates to typical sea surface nanolayer thicknesses. Our surface-specific SFG spectroscopy results show significant diminishing in the intensity of the dangling OH bond of surface water molecules consistent with organic molecules partitioning and replacing water at the air-seawater interface as the algal bloom progresses. Interestingly, we observe a new broad peak appear between 3500 cm<sup>-1</sup> to 3600 cm<sup>-1</sup> in the late stages of the bloom that is attributed to weak hydrogen bonding interactions of water to the surface-active biogenic matter. IRRAS confirms the presence of organic molecules at the surface as we observe increasing intensity of vibrational alkyl modes and the appearance of a proteinaceous amide band. Our work shows the often overlooked but vast potential of tracking changes in the interfacial regime of small-scale laboratory marine algal blooms. By coupling surface imaging and vibrational spectroscopies to complex, time-evolving, marine-relevant systems, we provide additional insight into unraveling the temporal complexity of sea spray aerosol compositions.

Factors Controlling Oxygen Depletion in Ice-Covered Lakes

1980 ◽  
Vol 37 (2) ◽  
pp. 185-194 ◽  
Author(s):  
Jack A. Mathias ◽  
Jan Barica
Keyword(s):  
Volume Ratio ◽  
Lake Management ◽  
Eddy Diffusion ◽  
Oxygen Depletion ◽  
Eutrophic Lakes ◽  
Experimental Lakes Area ◽  
Lake Volume ◽  
Basin Morphometry ◽  
Depletion Rate ◽  
Prairie Lakes

Winter oxygen depletion rates from four sets of Canadian lakes (prairie, southeastern Ontario, Arctic, and Experimental Lakes Area) differing in morphometry and trophic state, were analyzed. An inverse relationship was found between oxygen depletion rate and mean depth. The effect of lake trophic status on oxygen depletion rate was demonstrable after the influence of basin morphometry was removed by regression of oxygen depletion rate against the sediment area: lake volume ratio. The sediments of eutrophic lakes consumed oxygen about 3 times faster (0.23 g∙m−2∙d−1) than those of oligotrophic lakes (0.08 g∙m−2∙d−1), but water column respiration was about the same (0.01 g∙m−3∙d−1) for both groups of lakes. Data from prairie lakes showed that the winter oxygen consumption was limited by oxygen supply below an average whole-lake oxygen concentration of 3.8 mg∙L−1. The rate of eddy diffusion near the sediments in ice-covered prairie lakes was 3.72 ± 1.41 × 10−3 cm2∙s−1. Implications for lake management during the winter are discussed.Key words: oxygen, depletion, respiration, lakes, ice-covered, winter, sediments, model, consumption

Mitigating Impacts of Natural Hazards on Fishery Ecosystems

2008 ◽  
Keyword(s):  
United States ◽  
Hurricane Katrina ◽  
River System ◽  
Oxygen Depletion ◽  
Large River ◽  
Fish Kills ◽  
Subsistence Fisheries ◽  
Inland Fisheries ◽  
Stock Assessments ◽  
Fisheries Restoration

<em>Abstract</em>.—Extensive fish kills, primarily from dissolved oxygen depletion, were reported in rivers and associated backwaters throughout southern Mississippi following Hurricane Katrina. Of particular concern were fisheries associated with the Pascagoula River, the last physically unmodified large river system in the contiguous United States. Posthurricane stock assessments were conducted in 2006 to ascertain appropriate fisheries restoration actions for this internationally recognized natural resource. Emphasis focused on fishes that traditionally supported recreational, artisanal, and subsistence fisheries, primarily sunfish (Centrarchidae) and catfish (Ictaluridae). These fisheries were considered some of the more productive inland fisheries in the state prior to the storm.

scholarly journals A dinoflagellate exploits toxins to immobilize prey prior to ingestion

2010 ◽  
Vol 107 (5) ◽  
pp. 2082-2087 ◽  
Author(s):  
Jian Sheng ◽  
Edwin Malkiel ◽  
Joseph Katz ◽  
Jason E. Adolf ◽  
Allen R. Place
Keyword(s):  
High Speed ◽  
Algal Bloom ◽  
Harmful Algal Bloom ◽  
Fish Kills ◽  
Karlodinium Veneficum ◽  
Prey Behavior ◽  
Dense Suspensions ◽  
Holographic Microscopy ◽  
Critical Understanding ◽  
Grazing Pressures

Toxins produced by the harmful algal bloom (HAB) forming, mixotrophic dinoflagellate Karlodinium veneficum have long been associated with fish kills. To date, the perceived ecological role for toxins has been relief from grazing pressures. Here, we demonstrate that karlotoxins also serve as a predation instrument. Using high-speed holographic microscopy, we measure the swimming behavior of several toxic and nontoxic strains of K. veneficum and their prey, Storeatula major, within dense suspensions. The selected strains produce toxins with varying potency and dosages, including a nontoxic one. Results clearly show that mixing the prey with the predatory, toxic strains causes prey immobilization at rates that are consistent with the karlotoxins’ potency and dosage. Even prey cells that continue swimming slow down after exposure to toxic predators. The swimming characteristics of predators vary substantially in pure suspensions, as quantified by their velocity, radii of helical trajectories, and direction of helical rotation. When mixed with prey, all toxic strains that are involved in predation slow down. Furthermore, they substantially reduced their predominantly vertical migration, presumably to remain in the vicinity of their prey. Conversely, the nontoxic control strain does not alter its swimming and does not affect prey behavior. In separate experiments, we show that exposing prey to exogenous toxins also causes prey immobilization at rates consistent with potency. Clearly, the toxic predatory strains use karlotoxins as a means of stunning their prey, before ingesting it. These findings add a substantiated critical understanding for why some HAB species produce such complex toxin molecules.

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