Influence of Water Chemistry on Size Structure of Zooplankton Assemblages

1990 ◽  
Vol 47 (10) ◽  
pp. 1937-1943 ◽  
Author(s):  
Alan J. Tessier ◽  
Richard J. Horwitz
Keyword(s):  
Water Chemistry ◽  
Significant Variation ◽  
Size Structure ◽  
Water Hardness ◽  
Hard Water ◽  
The Body ◽  
Zooplankton Abundance ◽  
High Calcium ◽  
Influence Of Water ◽  
Physical And Chemical

A stratified-random selection of all lakes in the northeastern United States was sampled for zooplankton composition, and physical and chemical characteristics during midsummer 1986. In all, 146 lakes were sampled from five geographic subregions and three categories of water alkalinity. There was no significant variation in total zooplankton abundance among regions or alkalinity categories; however, the body-size structure of assemblages was dependent on both alkalinity and geographic subregion. The largest change in size structure occurred at alkalinity levels > 150 μeq∙L−1 and pH > 7.0, and appeared less related to change in pH than to variation in water hardness. This shift of size structure was caused by a loss of large-bodied zooplankton and an increase in small rotifers with decreasing water hardness. Exploratory analysis revealed that lake stratification also explained significant variation in zooplankton size structure, but was largely independent of the effects of water chemistry. We hypothesize that the association of large zooplankton with hard water is casual; large-bodied cladocerans may require high calcium levels.

scholarly journals Macroscale patterns of oceanic zooplankton composition and size structure

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Manoela C. Brandão ◽  
Fabio Benedetti ◽  
Séverine Martini ◽  
Yawouvi Dodji Soviadan ◽  
Jean-Olivier Irisson ◽  
...  
Keyword(s):  
Body Size ◽  
Community Composition ◽  
Climate Models ◽  
Size Structure ◽  
Fish Larvae ◽  
The Body ◽  
Community Level ◽  
Feeding Strategies ◽  
Size Spectrum ◽  
Zooplankton Abundance

AbstractOcean plankton comprise organisms from viruses to fish larvae that are fundamental to ecosystem functioning and the provision of marine services such as fisheries and CO2 sequestration. The latter services are partly governed by variations in plankton community composition and the expression of traits such as body size at community-level. While community assembly has been thoroughly studied for the smaller end of the plankton size spectrum, the larger end comprises ectotherms that are often studied at the species, or group-level, rather than as communities. The body size of marine ectotherms decreases with temperature, but controls on community-level traits remain elusive, hindering the predictability of marine services provision. Here, we leverage Tara Oceans datasets to determine how zooplankton community composition and size structure varies with latitude, temperature and productivity-related covariates in the global surface ocean. Zooplankton abundance and median size decreased towards warmer and less productive environments, as a result of changes in copepod composition. However, some clades displayed the opposite relationships, which may be ascribed to alternative feeding strategies. Given that climate models predict increasingly warmed and stratified oceans, our findings suggest that zooplankton communities will shift towards smaller organisms which might weaken their contribution to the biological carbon pump.

scholarly journals Correlation between water hardness and cardiovascular diseases in Mostar city, Bosnia and Herzegovina

2014 ◽  
Vol 12 (4) ◽  
pp. 817-823 ◽  
Author(s):  
Nevenka J. Knezović ◽  
Mustafa Memić ◽  
Mirela Mabić ◽  
Jasna Huremović ◽  
Ivanka Mikulić
Keyword(s):  
Human Subjects ◽  
Water Hardness ◽  
Population Group ◽  
Hard Water ◽  
Soft Water ◽  
Washington Dc ◽  
Significance Level ◽  
Chi Squared ◽  
Statistical Program ◽  
Physical And Chemical

The aim of this study was to determine the association of cardiovascular disease (CVD) of selected human subjects with the hardness of water they consume. Laboratory testing of physical and chemical parameters of water were made using standardized methods: Standard Methods 19th edn, 1995 (APHA, AWWA & WEF, Washington, DC), and ISO 7888:1985, ISO 10523:1998. Pearson's chi-squared test was used for the statistical analysis of data, with the significance level of 0.05. The obtained data were analysed using the statistical program SPSS 16.0. The study sample consisted of 1,021 individuals divided into two groups: soft water consumers, 603 individuals, and, hard water consumers, 618 individuals. Results indicate that a statistically significant (χ2 = 5.315; df = 1; p = 0.021) number of individuals with CVD drink soft water. The prevalence of CVD in the age group 45–60 years in the study area where soft water is consumed was 21.3% and in the study area where hard water is consumed the prevalence of CVD was 13.7%. The summary results indicate significant correlation between the prevalence of CVD in the population group who drink soft water. The value of the relative risk is 1.127.

Monitoring of Fluctuations in the Physical and Chemical Properties of a High-Calcium Fly Ash

1987 ◽  
Vol 113 ◽  
Author(s):  
Scott Schlorholtz ◽  
Ken Bergeson ◽  
Turgut Demirel
Keyword(s):  
Fly Ash ◽  
Chemical Properties ◽  
Operating Conditions ◽  
Physical And Chemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Morphological Studies ◽  
High Calcium ◽  
Physical And Chemical ◽  
And Chemical Properties

ABSTRACTThe physical and chemical properties of fly ash produced at Ottumwa Generating Station have been monitored since April, 1985. The fly ash is produced from burning a low sulfur, sub-bituminous coal obtained from the Powder River Basin near Gillette, Wyoming. One-hundred and sixty samples of fly ash were obtained during the two year period. All of the samples were subjected to physical testing as specified by ASTM C 311. About one-hundred of the samples were also subjected to a series of tests designed to monitor the self-cementing properties of the fly ash. Many of the fly ash samples were subjected to x-ray diffraction and fluorescence analysis to define the mineralogical and chemical composition of the bulk fly ash as a function of sampling date. Hydration products in selected hardened fly ash pastes, were studied by x-ray diffraction and scanning electron microscopy. The studies indicated that power plant operating conditions influenced the compressive strength of the fly ash paste specimens. Mineralogical and morphological studies of the fly ash pastes indicated that stratlingite formation occurred in the highstrength specimens, while ettringite was the major hydration product evident in the low-strength specimens.

TO THE QUESTION OF INDUSTRIAL AEROSOL CONTROL IN THE PROCESSING OF BLISTER COPPER

2021 ◽  
Author(s):  
O.G. Drugova ◽  
◽  
A.A. Fedoruk ◽  
T.N. Shtin
Keyword(s):  
Chemical Properties ◽  
The Body ◽  
Industrial Control ◽  
Silicon Iron ◽  
Carcinogenic Effect ◽  
Copper Zinc ◽  
Toxic Potential ◽  
Physical And Chemical ◽  
Industrial Aerosol ◽  
And Chemical Properties

Abstract. Due to the predominance of PM1 particles in the air samples, the following metals were found in the aerosol: copper, zinc, silicon, iron, lead, sulfur, arsenic, aluminum, antimony, tin, magnesium, cadmium and several other metals. The content of sulfates was significantly noted. These physical and chemical properties show a considerable toxic potential of industrial aerosol. The MPC of lead, sulfur and silicon dioxides, as well as nitrogen oxides and formaldehyde were detected in the working air. Meanwhile, copper, zinc, and iron did not exceed their MPC. Moreover, an underestimation of the aerosol was observed within the framework of industrial control. It has been found that the aerosol components may have an irritating, reprotoxic, allergenic, and carcinogenic effect on the body. Further consideration of the dispersed and chemical composition of the aerosol is required to determine the concentration of identified substances in the working air and the limiting components determining its biological effect.

INFLUENCE OF WATER CHEMISTRY ON THE ACUTE TOXICITY OF COPPER AND ZINC TO THE CLADOCERAN CERIODAPHNIA CF DUBIA

2005 ◽  
Vol 24 (7) ◽  
pp. 1667 ◽  
Author(s):  
Ross V. Hyne ◽  
Fleur Pablo ◽  
Moreno Julli ◽  
Scott J. Markich
Keyword(s):  
Acute Toxicity ◽  
Water Chemistry ◽  
Copper And Zinc ◽  
Influence Of Water

scholarly journals Prospects Of Using Walnut In Technologies Of Drinks

2015 ◽  
Vol 19 (2) ◽  
pp. 39-50
Author(s):  
Inna Tiurikova ◽  
Mykhailo Peresichnyi
Keyword(s):  
Raw Materials ◽  
Chemical Properties ◽  
The Body ◽  
Maturity Stage ◽  
Human Beings ◽  
Fruit And Vegetable ◽  
Biological Value ◽  
Vegetable Raw Materials ◽  
Main Components ◽  
Physical And Chemical

Abstract The results of studies in the field of beverage functionality using walnut are presented. The main components such as celery, Jerusalem artichokes, carrots, pumpkin and rhubarb, as a dietary supplement - extracts from walnut of milk-maturity stage are offered for creating blends. The basic physical and chemical properties of fruit and vegetable raw materials and semi-finished products created on the base of them have been studied, and their nutritional and biological value has been proved. Rational technologies of fruit and vegetable blends with nut additives have been identified. Their biological value has been confirmed. Drinks are recommended for use in the daily diet of human beings to satisfy thirst and enrich the body by biologically valuable components.

scholarly journals Insecticidal effects of insecticide, fungicide, complex fertilizer and wetting agent combinations depending on water hardness

2009 ◽  
Vol 24 (1) ◽  
pp. 43-49 ◽  
Author(s):  
Slavica Vukovic ◽  
Dusanka Indjic ◽  
Vojislava Bursic ◽  
Dragana Sunjka ◽  
Mila Grahovac
Keyword(s):  
Colorado Potato Beetle ◽  
Tap Water ◽  
Biological Effects ◽  
Water Hardness ◽  
Hard Water ◽  
Wetting Agent ◽  
Simultaneous Occurrence ◽  
Agricultural Practice ◽  
Potato Beetle ◽  
Novi Sad

Simultaneous occurrence of different harmful species in agricultural practice necessitates that different plant protection chemicals be applied at the same time (tank mix). Mix components differ in purpose, mode of action and/or formulation, while addition of no pesticide components (complex fertilizers, adjuvant and wetting agents) is widely practiced today. However, data concerning the effects of water quality used for preparation of working liquids on the biological effects of pesticides is still scarce. Therefore, the objective of this study was to determine insecticidal effects as depending on components used in mixes and water hardness. The effects of mixtures of thiametoxam (Actara 25-WG 0,07kg/ha) with azoxystrobin (Quadris 0.75 l/ha), mancozeb (Dithane M-70 2.5 kg/ha), a complex fertilizer (Mortonijc plus 3 kg/ha) and a wetting agent (Silwet L-77), depending on the components and water hardness (slightly hard (15.4 d?) - tap water from Novi Sad, and very hard (34.7 d?) - well water from Adica, a Novi Sad suburb), were determined in a bioassay based on adult mortality rate of the first generation of Colorado potato beetle (Leptinotarsa decemlineata Say). The mixtures were applied by a flooding method. The trial was set up to include four replications. Insecticidal effects were determined 24 h and 48 h after exposure. Thiametoxam effectiveness 24 h and 48 h after application in slightly hard water was 100% when the insecticide was applied alone and in double and triple mixes with the fungicides, complex fertilizer and wetting agent, showing no dependency on mix components. The tested adult population of Colorado potato beetle demonstrated high susceptibility to thiametoxam, while the other components had no impact in slightly hard water. In very hard water, 24 h after application, the insecticidal effect had the same level of significance to thiametoxam in double and triple mixes, with an exception of thiametoxam+mancozeb+Mortonijc plus and thiametoxam+mancozeb+wetting agent combinations, which showed significantly lower efficacy. After 48 h, substantially lower effectiveness, in comparison with the sole insecticide and other combinations, was only observed in thiametoksam+mancozeb+Mortonjic plus combination. Significantly lower efficacy of that combination is probably due to an incompatibility of the macozeb preparation and the complex fertilizer containing boron (B), which was evidenced only in very hard water.

scholarly journals DEET Degradation by Titanium Dioxide–Zeolite Nanocomposites: Effects of Aggregation State, Water Chemistry, and Natural Organic Matter

2020 ◽  
Author(s):  
Tchemongo B. Berté ◽  
Anthony S. Chen ◽  
Riya A. Mathew ◽  
Sheyda Shakiba ◽  
Stacey M. Louie
Keyword(s):  
Titanium Dioxide ◽  
Organic Matter ◽  
Water Treatment ◽  
Water Chemistry ◽  
Natural Organic Matter ◽  
Titanium Dioxide Nanoparticles ◽  
Hard Water ◽  
Aggregation State ◽  
Byproduct Formation ◽  
Partial Dissociation

Immobilization of titanium dioxide nanoparticles (TiO<sub>2</sub> NPs) facilitates their removal and reuse in water treatment applications. Composite materials of electrostatically-bound TiO<sub>2</sub> NPs and zeolite particles have been proposed, but limited mechanistic studies are available on their performance in complex media. This study delineates the relative importance of homo- and heteroaggregation, water chemistry, and surface fouling by natural organic matter (NOM) on the photocatalytic degradation of diethyltoluamide (DEET) by TiO<sub>2</sub>-zeolite composites. Zeolite adsorbs a portion of the DEET, rendering it unavailable for degradation; corrections for this adsorption depletion allowed appropriate comparison of the reactivity of the composites to the NPs alone. The TiO<sub>2</sub>-zeolite composites showed enhanced DEET degradation in moderately hard water (MHW) compared to deionized water (DIW), likely attributable to the influence of HCO<sub>3</sub><sup>−</sup>, whereas a net decline in reactivity was observed for the TiO<sub>2</sub> NPs alone upon homoaggregation in MHW. The composites also better maintained reactivity in the presence of NOM in MHW, as removal of Ca<sup>2+</sup> onto the zeolite mitigated fouling of the TiO<sub>2</sub> surface by NOM. However, NOM induced partial dissociation of the composites. DEET byproduct formation, identified by quadrupole–time of flight (QTOF) mass spectrometry, was generally unaffected by the zeolite, while NOM fouling favored de-ethylation over hydroxylation products. Overall, the most significant factor influencing TiO<sub>2</sub> reactivity toward DEET was NOM adsorption, followed by homoaggregation, electrolytes (here, MHW versus DIW), and heteroaggregation. These findings can inform a better understanding of NP reactivity in engineered water treatment applications.

Physical and chemical composition of the body of breeding sows with differing body subcutaneous fat depth at parturition, differing nutrition during lactation and differing litter size

1989 ◽  
Vol 48 (1) ◽  
pp. 203-212 ◽  
Author(s):  
C. T. Whittemore ◽  
H. Yang
Keyword(s):  
Chemical Composition ◽  
Energy Requirement ◽  
Subcutaneous Fat ◽  
Live Weight ◽  
Total Content ◽  
The Body ◽  
Large White ◽  
Body Protein ◽  
Weight Losses ◽  
Physical And Chemical

ABSTRACTThe physical and chemical composition of sows was determined at first mating (no. = 6), weaning the first litter (12) and 14 days after weaning the fourth litter (24). The sows were from 108 Large White/Landrace Fl hybrid gilts allocated in a factorial arrangement according to two levels of subcutaneous fatness at parturition (12 v. 22 mm P2), two levels of lactation feeding (3 v. 7 kg) and two sizes of sucking litter (six v. 10). Treatments significantly influenced the composition of dissected carcass fat and chemical lipid, but not composition of dissected lean and chemical protein. The final body protein mass of well fed sows at the termination of parity 4 was 41 kg, and the total content of gross energy (GE) in excess of 3000 MJ, with an average of 12·4 MJ GE per kg live weight; equivalent values for the less well fed sows were 33 kg and 9·4 MJ GE per kg live weight respectively. The weights of chemical lipid and protein could be predicted from the equations: lipid (kg) = -20·4 (s.e. 4·5) + 0·21 (s.e. 0·02) live weight + 1·5 (s.e. 0·2) P2; protein (kg) = -2·3 (s.e. 1·6) + 0·19 (s.e. 0·01) live weight - 0·22 (s.e. 0·07) P2. On average, sows lost 9 kg lipid and 3 kg protein in the course of the 28-day lactation; these being proportionately about 0·16 and 0·37 of the live-weight losses respectively. Maternal energy requirement for maintenance was estimated as 0·50 MJ digestible energy (DE) per kg M0·75, while the efficiency of use of DE for energy retention was 0·28.

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