Screen Mesh Size Affects Estimates of Macro- and Meio-benthos Abundance and Biomass in the Great Lakes

1981 ◽  
Vol 38 (9) ◽  
pp. 1027-1034 ◽  
Author(s):  
Thomas F. Nalepa ◽  
Andrew Robertson
Keyword(s):  
Great Lakes ◽  
Body Length ◽  
Water Depth ◽  
Lake Michigan ◽  
Mesh Size ◽  
Dry Weight ◽  
Head Capsule ◽  
Future Studies ◽  
Almost All ◽  
Screen Mesh

The efficiencies of screens with mesh openings of 595 and 106 μm in retaining, respectively, the macro- and meio-benthos were measured for samples taken in southeastern Lake Michigan. The use of these screens provides adequate estimates of dry weight biomass for both the macro- and meio-benthos, but serious underestimates of the numbers of many taxa, most notably naidids, enchytraeids, chironomids, nematodes, and rotifers, can result. For chironomids, retention on the 595-μm screen varied by species, with overall retention being closely related to both body length and head capsule width. Retention for certain macro-benthic taxa was significantly related to sampling date and water depth, indicating that future studies concerned with these variables should use mesh sizes small enough to retain all (or almost all) of the individuals of the taxa of interest.Key words: mesh size, screen efficiency, percent retention, macrobenthos, meibenthos, Lake Michigan

Profundal Testate Amoebae (Arcellacea) of Lake Superior and Lake Michigan

2020 ◽  
Vol 50 (1) ◽  
pp. 3-10 ◽  
Author(s):  
Krystyna M. Kornecki ◽  
Miriam E. Katz
Keyword(s):  
Pilot Study ◽  
Great Lakes ◽  
Water Depth ◽  
Lake Michigan ◽  
Lake Superior ◽  
Testate Amoebae ◽  
Sediment Surface ◽  
Valuable Insight ◽  
Water Interface ◽  
Large Lake

Abstract Sediment surface death assemblages of recent testate amoebae (Arcellacea) are reported from nine sites in Lake Superior and Lake Michigan. These are the first profundal sediment-water interface samples of testate amoebae described from either of the Great Lakes which provide valuable insight on deep-water, large-lake assemblages. Centropixid strains were present to abundant in shallower, nearshore sites (up to 66 m water depth). Assemblages at depths >40 m were dominated by Difflugia oblonga “tenuis.” The shallowest sample (26 m) was dominated by Centropyxis aculeata “discoides” and Difflugia oblonga “tenuis.” Over 100 tests per sample were observed from >100 m. Density of tests appears to be constrained by lithology rather than water depth. The deepest site (325 m) yielded low foraminiferal abundances. This pilot study provides a first step towards documenting the distribution of testate amoebae in the Great Lakes.

scholarly journals Spatial, Temporal, and Matrix Variability of Clostridium botulinum Type E Toxin Gene Distribution at Great Lakes Beaches

2015 ◽  
Vol 81 (13) ◽  
pp. 4306-4315 ◽  
Author(s):  
Rasanthi U. Wijesinghe ◽  
Ryan J. Oster ◽  
Sheridan K. Haack ◽  
Lisa R. Fogarty ◽  
Taaja R. Tucker ◽  
...  
Keyword(s):  
Great Lakes ◽  
Clostridium Botulinum ◽  
Lake Michigan ◽  
Dry Weight ◽  
Toxin Gene ◽  
Average Water Temperature ◽  
Content Type ◽  
Gene Copies ◽  
Clostridium Botulinum Type E ◽  
City State

ABSTRACTClostridium botulinumtype E toxin is responsible for extensive mortality of birds and fish in the Great Lakes. TheC. botulinum bontEgene that produces the type E toxin was amplified with quantitative PCR from 150 sloughed algal samples (primarilyCladophoraspecies) collected during summer 2012 from 10 Great Lakes beaches in five states; concurrently, 74 sediment and 37 water samples from four sites were also analyzed. ThebontEgene concentration in algae was significantly higher than in water and sediment (P< 0.05), suggesting that algal mats provide a better microenvironment forC. botulinum. ThebontEgene was detected most frequently in algae at Jeorse Park and Portage Lake Front beaches (Lake Michigan) and Bay City State Recreation Area beach on Saginaw Bay (Lake Huron), where 77, 100, and 83% of these algal samples contained thebontEgene, respectively. The highest concentration ofbontEwas detected at Bay City (1.98 × 105gene copies/ml of algae or 5.21 × 106g [dry weight]). This study revealed that thebontEgene is abundant in the Great Lakes but that it has spatial, temporal, and matrix variability. Further, embayed beaches, low wave height, low wind velocity, and greater average water temperature enhance thebontEoccurrence.

PHYTOTOXICITY OF WASTEWATER CONTAINING CADMIUM (Cd) USING OLEANDER

2020 ◽  
Vol 51 (4) ◽  
pp. 1231-1238
Author(s):  
Zeki & Ridha
Keyword(s):  
Translocation Factor ◽  
Preliminary Test ◽  
Dry Weight ◽  
Exposure Dose ◽  
Test Duration ◽  
Plant Analysis ◽  
Wet Weight ◽  
Simulated Wastewater ◽  
Almost All ◽  
Plant Shoots

This study was aimed to investigate the ability of N.oleander to remove Cadmium (Cd) from wastewater. A prolonged toxicity test was performed in a single exposure and run for 65 days with various concentrations of Cd. Plants were grown in sand medium and irrigated with simulated wastewater contaminated with Cd, using different concentrations (0, 10, 25, 50, 75 mg/L), which were chosen based on previous preliminary test. The results of physical observation of the plants didn’t show any withering symptoms. The Cd concentration in plants increased, while in water decreased. The results of plant analysis showed that Cd concentration in plant shoots (stems and leaves) was higher than that in roots for almost all exposure doses along the test duration. The concentration of Cd in water decreased significantly from the first week of the test and become (0 mg/l) on day-35 for 10 and 25 mg/l exposure doses, while exceeded the permissible limits for 50 and 75 mg/l exposure doses and were 0.14 and 0.91 mg/l, respectively. Wet weight and dry weight of Oleander decreased with increasing Cd concentration level except for 10 mg/l exposure dose where the plant wet weight and dry weight increased at the end of the test. Bioaccumulation factor (BAF) and Translocation Factor (TF) was found to be greater than 1, indicating that Oleander is a successful hyperaccumulator for Cd.

Zebra Mussels as Biomonitors for Organic Contaminants in the Lower Great Lakes

1996 ◽  
Vol 31 (2) ◽  
pp. 411-432 ◽  
Author(s):  
Michael E. Comba ◽  
Janice L. Metcalfe-Smith ◽  
Klaus L.E. Kaiser
Keyword(s):  
Great Lakes ◽  
Organic Contaminants ◽  
Lake Erie ◽  
Soft Tissues ◽  
Lake Ontario ◽  
Dry Weight ◽  
Zebra Mussels ◽  
Organic Contamination ◽  
Contamination Levels ◽  
St Lawrence River

Abstract Zebra mussels were collected from 24 sites in Lake Erie, Lake Ontario and the St. Lawrence River between 1990 and 1992. Composite samples of whole mussels (15 sites) or soft tissues (9 sites) were analyzed for residues of organochlo-rine pesticides and PCBs to evaluate zebra mussels as biomonitors for organic contaminants. Mussels from most sites contained measurable quantities of most of the analytes. Mean concentrations were (in ng/g, whole mussel dry weight basis) 154 ΣPCB, 8.4 ΣDDT, 3.5 Σchlordane, 3.4 Σaldrin, 1.4 ΣBHC, 1.0 Σendosulfan, 0.80 mirex and 0.40 Σchlorobenzene. Concentrations varied greatly between sites, i.e., from 22 to 497 ng/g for ΣPCB and from 0.08 to 11.6 ng/g for ΣBHC, an indication that mussels are sensitive to different levels of contamination. Levels of ΣPCB and Σendosulfan were highest in mussels from the St. Lawrence River, whereas mirex was highest in those from Lake Ontario. Overall, mussels from Lake Erie were the least contaminated. These observations agree well with the spatial contaminant trends shown by other biomoni-toring programs. PCB congener class profiles in zebra mussels are also typical for nearby industrial sources, e.g., mussels below an aluminum casting plant contained 55% di-, tri- and tetrachlorobiphenyls versus 31% in those upstream. We propose the use of zebra mussels as biomonitors of organic contamination in the Great Lakes.

scholarly journals Establishment of Regional Phytoremediation Buffer Systems for Ecological Restoration in the Great Lakes Basin, USA. I. Genotype × Environment Interactions

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 430 ◽  
Author(s):  
Ronald S. Zalesny ◽  
Andrej Pilipović ◽  
Elizabeth R. Rogers ◽  
Joel G. Burken ◽  
Richard A. Hallett ◽  
...  
Keyword(s):  
Great Lakes ◽  
Best Management Practices ◽  
Management Practices ◽  
Recurrent Selection ◽  
Lake Michigan ◽  
Great Lakes Basin ◽  
Annual Increment ◽  
Climate Conditions ◽  
The North ◽  
Local Soil

Poplar remediation systems are ideal for reducing runoff, cleaning groundwater, and delivering ecosystem services to the North American Great Lakes and globally. We used phyto-recurrent selection (PRS) to establish sixteen phytoremediation buffer systems (phyto buffers) (buffer groups: 2017 × 6; 2018 × 5; 2019 × 5) throughout the Lake Superior and Lake Michigan watersheds comprised of twelve PRS-selected clones each year. We tested for differences in genotypes, environments, and their interactions for health, height, diameter, and volume from ages one to four years. All trees had optimal health. Mean first-, second-, and third-year volume ranged from 71 ± 26 to 132 ± 39 cm3; 1440 ± 575 to 5765 ± 1132 cm3; and 8826 ± 2646 to 10,530 ± 2110 cm3, respectively. Fourth-year mean annual increment of 2017 buffer group trees ranged from 1.1 ± 0.7 to 7.8 ± 0.5 Mg ha−1 yr−1. We identified generalist varieties with superior establishment across a broad range of buffers (‘DM114’, ‘NC14106’, ‘99038022’, ‘99059016’) and specialist clones uniquely adapted to local soil and climate conditions (‘7300502’, ‘DN5’, ‘DN34’, ‘DN177’, ‘NM2’, ‘NM5’, ‘NM6’). Using generalists and specialists enhances the potential for phytoremediation best management practices that are geographically robust, being regionally designed yet globally relevant.

Development and application of a simple procedure for toxicity testing using immobilized algae

1996 ◽  
Vol 33 (6) ◽  
pp. 129-138 ◽  
Author(s):  
Mohammad I. Abdel-Hamid
Keyword(s):  
Simple Procedure ◽  
Algal Growth ◽  
Toxicity Testing ◽  
Dry Weight ◽  
Toxicity Assessment ◽  
Response Curves ◽  
Response Parameter ◽  
Test Alga ◽  
Almost All ◽  
Immobilized Algae

A simple microplate technique was adopted for toxicity assessment of a number of pesticides including six herbicides (Atrazine, Dichloroprop, Glyphosphate, Chlorsulfuron, MCPA, and Simazine), an insecticide (Dimethoate) and a fungicide (Propiconazol). Growth response of free and immobilized cultures of the green chlorococcal algae Selenastrum capricornumtum to different treatments of these pesticides was tested and compared. The biotests were carried out under conditions optimal for the growth of the test alga. Algal growth was exposed in terms of dry weight, and was employed as the toxicity-response parameter. Dose-response curves were used to calculate the toxicity of the tested compounds in terms of EC50. Based on EC50 values, the responses of both immobilized and free cultures were quite similar for almost all the treatments. The technique facilitated the visual detection of the lowest toxic concentration giving no detectable algal growth (EC100). The technique is quite simple, rapid, practical, accurate, and space saving. It suggested that batteries of immobilized algae could replace free cultures in studies of toxicity testing.

scholarly journals Soft bodies make estimation hard: correlations among body dimensions and weights of multiple species of sea cucumbers

2015 ◽  
Vol 66 (10) ◽  
pp. 857 ◽  
Author(s):  
James Prescott ◽  
Shijie Zhou ◽  
Andhika P. Prasetyo
Keyword(s):  
Power Function ◽  
Body Length ◽  
Sea Cucumber ◽  
Dry Weight ◽  
Basic Knowledge ◽  
Small Scale ◽  
Body Width ◽  
Sea Cucumbers ◽  
Body Dimensions ◽  
Wet Weight

Tropical sea cucumbers are commonly exploited by small-scale, poorly managed fisheries. A fundamental problem in managing sea cucumber fisheries is the lack of basic knowledge of important life history characteristics for most species. As a result of plastic body dimensions, biological research on this group of animals becomes exceptionally challenging. To improve our understanding of essential biological parameters, we conducted a study to investigate correlations among various body measurements. We analysed a total of 18 sea cucumber species and more than 6600 individuals collected at Scott Reef in the Timor Sea, north-west Australia. We used hierarchical Bayesian errors-in-variables models to specifically take into account measurement errors that are obviously unavoidable. The measures included three types of weights (wet weight, gutted weight and dry weight) and two body dimensions (length and width). The modelling reveals that using both body length and width as independent variables, wet weight increases approximately linearly with body length, but is a power function (~1.6) of body width, although variability exists among species. Dry weight tends to increase more slowly with body length, but has a similar power function of body width. Linear relationships are established between the three types of weights. On average, ~11% of a live specimen and ~16% of a gutted specimen is processed to the commercially traded dry body wall. Our results can be applied to sea cucumbers in other areas and can be useful for data standardisation and size-based fisheries management.

scholarly journals Correlation of morphological parameters of donkey from Austria

2021 ◽  
Vol 53 (2) ◽  
Author(s):  
Darko Drobnjak ◽  
Radka Vlaeva ◽  
Goran Stanišić ◽  
Radomir Mandić ◽  
Natalija Grittner ◽  
...  
Keyword(s):  
Body Length ◽  
Pearson Correlation ◽  
Good Reason ◽  
Statistical Correlation ◽  
Head Length ◽  
Chest Circumference ◽  
Average Height ◽  
Face Width ◽  
Equus Asinus ◽  
Almost All

The donkey, as a work animal, is gradually losing its value. Agriculture industrialization, mechanization of many processes on mountain and valley farms have lead to a reduction of donkey livestock. This reduction gives cause for concern, and is good reason to study all aspects of these domestic animals in order to revive its role, to restart livestock growth in its familiar habitats, and to introduce it into new environments. This study focuses on these aspects. The domestic donkey (Equus asinus) originated from Africa, and there are two kinds of African donkeys: Nubian and Somali. Their enormous, almost mystical, endurance is well known. There is no place in the world where a donkey is not able to perform the most difficult work, above all in transporting goods. A donkey has an amazing capability of stable movement through the most difficult places. For study sample consisted of 44 donkeys (28 males and 16 females) from Austria. The following morphometric parameters were analysed: height at the withers, height at the back, height of the croup, body length, chest depth, chest width, chest circumference anterior, chest circumference posterior, shin circumference, head length, skull length, face length, skull width, face width, length of ears. Measurements were performed using a ruler, tape measure and vernier callipers. The average height at the withers of males was 116.40 cm, ranging from 99.60 to 140.60 cm, while for females, the average was 102.38 cm, ranging from 90.50 to 125.70 cm. Body length of males was on average 121.85 cm with a standard deviation of 11.79, while the mean body length for females is 115.80 cm, with a range of 101.00 to 131.00 cm. Male head length ranged from 48.00 to 71.00 cm, with an average of 55.60 cm, while in females, head length was on average 50.06 cm, ranging from 43.00 to 56.00 cm. Using the Pearson correlation, a very significant or significant positive statistical correlation was observed between almost all parameters of males, while for females, Pearson correlation values had slightly different values than for males. There was no statistically significant correlation between chest width and anterior chest circumference with nearly any other parameters. For females, a negative correlation between the skull width and all other parameters was also observed.

Paleohydrology of the upper Laurentian Great Lakes from the late glacial to early Holocene

2009 ◽  
Vol 71 (3) ◽  
pp. 397-408 ◽  
Author(s):  
Andy Breckenridge ◽  
Thomas C. Johnson
Keyword(s):  
Great Lakes ◽  
Lake Michigan ◽  
Lake Superior ◽  
Late Glacial ◽  
Lake Huron ◽  
Michigan Basin ◽  
Great Lakes Basin ◽  
Lake Agassiz ◽  
Sharp Drop ◽  
Freshwater Fluxes

AbstractBetween 10,500 and 9000 cal yr BP, δ18O values of benthic ostracodes within glaciolacustrine varves from Lake Superior range from − 18 to − 22‰ PDB. In contrast, coeval ostracode and bivalve records from the Lake Huron and Lake Michigan basins are characterized by extreme δ18O variations, ranging from values that reflect a source that is primarily glacial (∼ − 20‰ PDB) to much higher values characteristic of a regional meteoric source (∼ − 5‰ PDB). Re-evaluated age models for the Huron and Michigan records yield a more consistent δ18O stratigraphy. The striking feature of these records is a sharp drop in δ18O values between 9400 and 9000 cal yr BP. In the Huron basin, this low δ18O excursion was ascribed to the late Stanley lowstand, and in the Lake Michigan basin to Lake Agassiz flooding. Catastrophic flooding from Lake Agassiz is likely, but a second possibility is that the low δ18O excursion records the switching of overflow from the Lake Superior basin from an undocumented northern outlet back into the Great Lakes basin. Quantifying freshwater fluxes for this system remains difficult because the benthic ostracodes in the glaciolacustrine varves of Lake Superior and Lake Agassiz may not record the average δ18O value of surface water.

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