Study on the Selective Grazing of Zooplankton in Plankton Ecosystem

2013 ◽  
Vol 864-867 ◽  
pp. 17-21
Author(s):  
Yan Lin Zheng ◽  
Zhuo Ying Lv
Keyword(s):  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Marine Ecosystem ◽  
Laboratory Data ◽  
Ecosystem Dynamics ◽  
Human Environment ◽  
Grazing Behavior ◽  
Toxic Phytoplankton ◽  
Type Iv ◽  
Selective Grazing

Harmful algal blooms (Habs) caused great harm to the human environment. Habs occurrence was connected with other types of plankton. This relationship may be restrictive, and may also be promotional. Selectivity of zooplankton grazing has an important influence on the Habs. The behavior of zooplankton selective grazing was studied in the plankton ecosystem formed by three populations of nontoxic phytoplankton-toxic phytoplankton-zooplankton (NTP-TTP-Z) system. The selective grazing function of zooplankton on toxic phytoplankton and non-toxic phytoplankton was built based on Holling type IV functional response. Numerical simulation was given depending on the laboratory data. Results show that the models nicely explained the selective grazing behavior of zooplankton in the three species ecosystem, and provided key parameters for the marine ecosystem dynamics models.

Using Fundamental Optical Property Sensors for Characterization of Biogeochemical Materials and Processes in Marine Waters

2008 ◽  
Vol 42 (1) ◽  
pp. 75-83 ◽  
Author(s):  
Casey Moore
Keyword(s):  
Optical Properties ◽  
Optical Property ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Natural Waters ◽  
Harmful Algal Bloom ◽  
Light Level ◽  
Ecosystem Dynamics ◽  
Wide Range ◽  
Biogeochemical Parameters

Over the past ten years, efforts to characterize the optical properties of Earth's natural waters have largely merged with the need to better understand underlying biological and chemical processes. Fundamental optical properties such as light level, absorption, scattering and fluorescence are now being utilized with increasing effectiveness to specify particulate and dissolved in-water components in a wide range of applications, including detection of harmful algal blooms, studying ecosystem dynamics, monitoring the effect of industrial and agricultural pollutants, and understanding carbon sequestration processes in the oceans. A diverse offering of commercial optical sensing products capable for research, routine measurements, and in some cases, operational monitoring are now available. These technologies have provided the scientific community with a set of tools for developing, testing, and placing into practice analytical and semi-analytical methods to infer specific biogeochemical parameters and processes. As a result, new, more specialized sensors are now emerging. New sensors couple basic optical property measurements with processing algorithms to provide specific indicators for Harmful Algal Bloom (HAB) identification, carbon products, nutrients, and particle size distributions. The basic measurement methods are described and examples of devices incorporating them are provided to illustrate their use in modern oceanographic research and monitoring.

scholarly journals Filtration of the Microalga Amphidinium carterae by the Polychaetes Sabella spallanzanii and Branchiomma luctuosum: A New Tool for the Control of Harmful Algal Blooms?

2022 ◽  
Vol 10 (1) ◽  
pp. 156
Author(s):  
Loredana Stabili ◽  
Margherita Licciano ◽  
Adriana Giangrande ◽  
Carmela Caroppo
Keyword(s):  
Human Health ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Feeding Activity ◽  
Marine Ecosystem ◽  
Harmful Algae ◽  
Retention Efficiency ◽  
Amphidinium Carterae ◽  
Negative Impacts ◽  
Harmful Microalgae

Harmful algal blooms (HABs) are extreme biological events representing a major issue in marine, brackish, and freshwater systems worldwide. Their proliferation is certainly a problem from both ecological and socioeconomic contexts, as harmful algae can affect human health and activities, the marine ecosystem functioning, and the economy of coastal areas. Once HABs establish, valuable and environmentally friendly control actions are needed to reduce their negative impacts. In this study, the influence exerted by the filter-feeding activity of the two sabellid polychaetes Branchiomma luctuosum (Grube) and Sabella spallanzanii (Gmelin) on a harmful dinoflagellate was investigated. Clearance rates (C) and retention efficiencies were estimated by employing the microalga Amphidinium carterae Hulburt. The Cmax was 1.15 ± 0.204 L h−1 g−1 DW for B. luctuosum and 0.936 ± 0.151 L h−1 g−1 DW for S. spallanzanii. The retention efficiency was 72% for B. luctuosum and 68% for S. spallanzanii. Maximum retention was recorded after 30 min for both species. The obtained results contribute to the knowledge of the two polychaetes’ filtration activity and to characterize the filtration process on harmful microalgae in light of the protection of water resources and human health. Both species, indeed, were extremely efficient in removing A. carterae from seawater, thus suggesting their employment as a new tool in mitigation technologies for the control of harmful algae in marine environments, as well as in the aquaculture facilities where HABs are one of the most critical threats.

Harmful algal blooms and eutrophication along the mexican coast of the Gulf of Mexico large marine ecosystem

2017 ◽  
Vol 22 ◽  
pp. 120-128 ◽  
Author(s):  
Marco J. Ulloa ◽  
Porfirio Álvarez-Torres ◽  
Karla P. Horak-Romo ◽  
Rogelio Ortega-Izaguirre
Keyword(s):  
Gulf Of Mexico ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Marine Ecosystem ◽  
Large Marine Ecosystem

scholarly journals Planktonic algal blooms from 2000 to 2015 in Acapulco Bay, Guerrero, Mexico

2018 ◽  
pp. 61-93 ◽  
Author(s):  
Maria Esther A. Meave del Castillo ◽  
María Eugenia Zamudio Resendiz
Keyword(s):  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Southern Oscillation ◽  
Marine Ecosystem ◽  
Cold Season ◽  
Paralytic Shellfish Poisoning ◽  
Shellfish Poisoning ◽  
Cell Counts ◽  
Paralytic Shellfish ◽  
Using Data

Background and Aims: Harmful algal blooms (HABs) affect the marine ecosystem in multiple ways. The objective was to document the species that produced blooms in Acapulco Bay over a 15-year period (2000-2015) and analyze the presence of these events with El Niño-Southern Oscillation (ENSO).Methods: Thirty-five collections, made during the years 2000, 2002-2004, 2006-2011, 2013-2015, were undertaken with phytoplankton nets and Van Dorn bottle, yielding 526 samples, of which 423 were quantified using the Utermöhl method. The relationship of HAB with ENSO was made with standardized values of Multivariate ENSO Index (MEI) and the significance was evaluated with the method quadrant sums of Olmstead-Tukey.Key results: Using data of cell density and high relative abundance (>60%), 53 blooms were recorded, most of them occurring during the rainy season (June-October) and dry-cold season (November-March), plus 37 blooms reported by other authors. These 90 blooms were composed of 40 taxa: 21 diatoms and 19 dinoflagellates, the former mostly innocuous. Sixty-seven blooms had species reported as noxious, of which 11 species commonly produce toxic HAB. Toxic taxa are Pseudo-nitzschia spp. (four taxa), and seven dinoflagellates.Conclusions: Abundance analyses of Pyrodinium bahamense var. compressum and Gymnodinium catenatum against values of MEI showed a clear tendency to produce HAB in La Niña conditions. Both taxa, producers of saxitoxins, cause paralytic shellfish poisoning (PSP) and coexist in Acapulco; therefore, they present a risk to human health. Another noxious 52 taxa found in Acapulco were currently considered potential HABs, because they have been recorded at low densities. Given the sharp differences in density values of bloom-forming species found in this work compared to those reported by other authors on similar dates, it is important to perform calibration tests to rule out possible errors in cell counts.

scholarly journals Intraspecific facilitation by allelochemical mediated grazing protection within a toxigenic dinoflagellate population

2015 ◽  
Vol 282 (1798) ◽  
pp. 20141268 ◽  
Author(s):  
Uwe John ◽  
Urban Tillmann ◽  
Jennifer Hülskötter ◽  
Tilman J. Alpermann ◽  
Sylke Wohlrab ◽  
...  
Keyword(s):  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Phenotypic Diversity ◽  
Marine Ecosystem ◽  
Paralytic Shellfish Poisoning ◽  
Alexandrium Tamarense ◽  
Shellfish Poisoning ◽  
Coastal Marine ◽  
The Impact ◽  
Intraspecific Facilitation

Dinoflagellates are a major cause of harmful algal blooms (HABs), with consequences for coastal marine ecosystem functioning and services. Alexandrium fundyense (previously Alexandrium tamarense ) is one of the most abundant and widespread toxigenic species in the temperate Northern and Southern Hemisphere and produces paralytic shellfish poisoning toxins as well as lytic allelochemical substances. These bioactive compounds may support the success of A. fundyense and its ability to form blooms. Here we investigate the impact of grazing on monoclonal and mixed set-ups of highly (Alex2) and moderately (Alex4) allelochemically active A. fundyense strains and a non-allelochemically active conspecific (Alex5) by the heterotrophic dinoflagellate Polykrikos kofoidii . While Alex4 and particularly Alex5 were strongly grazed by P. kofoidii when offered alone, both strains grew well in the mixed assemblages (Alex4 + Alex5 and Alex2 + Alex5). Hence, the allelochemical active strains facilitated growth of the non-active strain by protecting the population as a whole against grazing. Based on our results, we argue that facilitation among clonal lineages within a species may partly explain the high genotypic and phenotypic diversity of Alexandrium populations. Populations of Alexandrium may comprise multiple cooperative traits that act in concert with intraspecific facilitation, and hence promote the success of this notorious HAB species.

scholarly journals Satellite detection of dinoflagellate blooms off California by UV reflectance ratios

Elem Sci Anth ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Mati Kahru ◽  
Clarissa Anderson ◽  
Andrew D. Barton ◽  
Melissa L. Carter ◽  
Dylan Catlett ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Marine Ecosystem ◽  
Ocean Color ◽  
Optical Data ◽  
Blue Band ◽  
Chl A ◽  
Color Sensor ◽  
Uv Reflectance

As harmful algae blooms are increasing in frequency and magnitude, one goal of a new generation of higher spectral resolution satellite missions is to improve the potential of satellite optical data to monitor these events. A satellite-based algorithm proposed over two decades ago was used for the first time to monitor the extent and temporal evolution of a massive bloom of the dinoflagellate Lingulodinium polyedra off Southern California during April and May 2020. The algorithm uses ultraviolet (UV) data that have only recently become available from the single ocean color sensor on the Japanese GCOM-C satellite. Dinoflagellates contain high concentrations of mycosporine-like amino acids and release colored dissolved organic matter, both of which absorb strongly in the UV part of the spectrum. Ratios <1 of remote sensing reflectance of the UV band at 380 nm to that of the blue band at 443 nm were used as an indicator of the dinoflagellate bloom. The satellite data indicated that an observed, long, and narrow nearshore band of elevated chlorophyll-a (Chl-a) concentrations, extending from northern Baja to Santa Monica Bay, was dominated by L. polyedra. In other high Chl-a regions, the ratios were >1, consistent with historical observations showing a sharp transition from dinoflagellate- to diatom-dominated waters in these areas. UV bands are thus potentially useful in the remote sensing of phytoplankton blooms but are currently available only from a single ocean color sensor. As several new satellites such as the NASA Plankton, Aerosol, Cloud, and marine Ecosystem mission will include UV bands, new algorithms using these bands are needed to enable better monitoring of blooms, especially potentially harmful algal blooms, across large spatiotemporal scales.

Harmful algal blooms in fresh and marine water systems: The role of toxin producing phytoplankton

2016 ◽  
Vol 09 (03) ◽  
pp. 1650043 ◽  
Author(s):  
Nilesh Kumar Thakur ◽  
S. K. Tiwari ◽  
Ranjit Kumar Upadhyay
Keyword(s):  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Functional Responses ◽  
Toxic Phytoplankton ◽  
Space And Time ◽  
Spatially Distributed ◽  
High Predation ◽  
Predator Switching ◽  
Parameter Values

In this paper, we have investigated a model with three interacting species: non-toxic phytoplankton, toxic phytoplankton and zooplankton with Holling type II and III functional responses over the space and time. The role of toxin producing phytoplankton (TPP) has been studied. We have presented the theoretical analysis of pattern formation in spatially distributed population with local diffusion. The paper highlights the heterogeneity of HABs over space and time. The choice of parameter values and the functional response is important to study the effect of TPP, also it would depend more on the nonlinearity of the system. With the help of numerical simulations, we have observed the spatial and spatiotemporal patterns for plankton system. This study demonstrates that TPP plays an important role in controlling the dynamics. We have observed that prey’s anti-predator efforts promote predator switching. It has been found that high predation of TPP helps for the coexistence of toxic, non-toxic phytoplankton and zooplankton population.

scholarly journals Sensitivity of a Satellite Algorithm for Harmful Algal Bloom Discrimination to the Use of Laboratory Bio-optical Data for Training

2020 ◽  
Vol 7 ◽  
Author(s):  
Victor Martinez-Vicente ◽  
Andrey Kurekin ◽  
Carolina Sá ◽  
Vanda Brotas ◽  
Ana Amorim ◽  
...  
Keyword(s):  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Satellite Images ◽  
Harmful Algal Bloom ◽  
A Priori ◽  
Laboratory Data ◽  
Optical Data ◽  
Training Dataset ◽  
Chlorophyll Concentrations

Early detection of dense harmful algal blooms (HABs) is possible using ocean colour remote sensing. Some algorithms require a training dataset, usually constructed from satellite images with a priori knowledge of the existence of the bloom. This approach can be limited if there is a lack of in situ observations, coincident with satellite images. A laboratory experiment collected biological and bio-optical data from a culture of Karenia mikimotoi, a harmful phytoplankton dinoflagellate. These data showed characteristic signals in chlorophyll-specific absorption and backscattering coefficients. The bio-optical data from the culture and a bio-optical model were used to construct a training dataset for an existing statistical classifier. MERIS imagery over the European continental shelf were processed with the classifier using different training datasets. The differences in positive rates of detection of K. mikimotoi between using an algorithm trained with purely manually selected areas on satellite images and using laboratory data as training was overall <1%. The difference was higher, <15%, when using modeled optical data rather than laboratory data, with potential for improvement if local average chlorophyll concentrations are used. Using a laboratory-derived training dataset improved the ability of the algorithm to distinguish high turbidity from high chlorophyll concentrations. However, additional in situ observations of non-harmful high chlorophyll blooms in the area would improve testing of the ability to distinguish harmful from non-harmful high chlorophyll blooms. This approach can be expanded to use additional wavelengths, different satellite sensors and different phytoplankton genera.

scholarly journals Mathematical analysis of plankton population dynamics

2020 ◽  
Vol 16 (1) ◽  
pp. 109-114
Author(s):  
Fatin Nadiah Yussof ◽  
Normah Maan ◽  
Nadzri Reba
Keyword(s):  
Mathematical Model ◽  
Population Dynamics ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Health Effect ◽  
Economic Loss ◽  
Toxic Chemicals ◽  
Toxic Phytoplankton ◽  
Interior Equilibrium ◽  
Plankton Population

Harmful algal blooms (HABs) event that causes enormous economic loss and health effect raises concerns among environmentalists. In this paper, a mathematical model of interaction between nutrient, toxin-producing phytoplankton (TPP), non-toxic phytoplankton (NTP), zooplankton, and toxic chemicals is proposed to study on how the process of these HABs occurred. The model of interaction is represented by Ordinary Differential Equations (ODEs) and stability analysis of the model is conducted. Several conditions for the system to be stable around trivial and interior equilibrium point are obtained. From the analysis, it is observed that under nutrient limitation, the amounts of toxic chemicals secreted out by the TPP are increased. As a result, NTP population and zooplankton population are affected by the situation. If this situation is prolonged, this will result in the extinction of both populations. Overall, this study shows that TPP release more toxic chemicals when the nutrient is limited and gives a better understanding on the occurrence of HABs event. 

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