Rates of Mortality, Growth, and Biomass Production of Lymnaea palustris During Chronic Exposure to Lead

1978 ◽  
Vol 35 (8) ◽  
pp. 1109-1115 ◽  
Author(s):  
U. Borgmann ◽  
O. Kramar ◽  
C. Loveridge
Keyword(s):  
Growth Rate ◽  
Mortality Rate ◽  
Biomass Production ◽  
Lead Concentration ◽  
Lead Toxicity ◽  
Dry Weight ◽  
Freshwater Snail ◽  
Rate Function ◽  
Lead Uptake ◽  
Percent Mortality

Lymnaea palustris, a freshwater snail, was exposed to lead in a continuous-flow system from newly laid eggs until reproductive maturity. Lead, at concentrations as low as 19 μg∙L−1, caused a significant increase in the mortality rate, although the growth rate was not affected. The lead-induced mortality was proportional to the lead concentration raised to the exponent 2.5. The analysis of mortality as a rate function was found superior to the use of the more conventional LC50 (concentration resulting in 50% mortality). A plot of the logarithm of the lead-induced mortality against log lead concentration is linear and has the same slope as plots of double logarithms of the inverse survival at any one time versus log lead concentration or log time versus log LC50 or log LT50 (time to 50% mortality) versus log lead concentration. The mortality rate, unlike the percent mortality, is independent of time and can be combined directly with the growth rate to estimate the biomass production rate. A 50% drop in the rate of biomass production was observed at 36 μg∙L−1 and a drop to 0 production at 48 μg∙L−1. Lead uptake in whole snails was found to be proportional to the lead concentration in the water, giving a concentration factor of 8500 on a dry weight basis. Key words: snails, lead, toxicity, biomass production, bioaccumulation

scholarly journals Effects of lead on growth, yield and mineral nutrition of rice (Oryza sativa L.)

2020 ◽  
Vol 5 (2) ◽  
pp. 83-92
Author(s):  
P Jasmin ◽  
WZ Prian ◽  
MN Mondol ◽  
SM Ullah ◽  
AS Chamon
Keyword(s):  
Oryza Sativa ◽  
Lead Concentration ◽  
Oryza Sativa L ◽  
Poultry Litter ◽  
Growth Yield ◽  
Lead Toxicity ◽  
Dry Weight ◽  
Cow Dung ◽  
Lead Uptake ◽  
Positive Effects

A pot experiment was conducted to evaluate the effect of lead (50, 100, 150 and 200 mg kg-1) on rice (Oryza sativa) and remediation of metal contamination by applying cow dung, poultry litter and lime to alleviate lead toxicity. The lengths, fresh and dry weights of shoot, root and macronutrients decreased with increasing level of lead compared to the control. The maximum reduction was observed in the pots treated with 200 mg kg-1 lead (19.50 and 20.03% for grain, 17.15 and 19.75% for shoot and 17.96 and 30.02% for root on the fresh and dry weight, respectively). The highest reduction in macronutrient content was observed in 200 mg kg-1 lead treated pot where N, P, K, Ca and Mg concentrations were reduced by 31.14, 47.44, 22.49, 21.84 and 31.58% for shoot and 28.95, 55.64, 37.5, 49.33 and 23% for root, respectively. On the other hand lead concentration in roots and shoots were increased with increasing lead treatment compared to the control. Treatments of the amendments (cow dung, poultry litter and lime) had positive effects though cow dung outshining the rest of them. This particular organic matter had considerable decreasing impacts in lead uptake by rice. Cow dung treated pots increased fresh and dry weight by 31.48 and 32.07% for grain, 14.08 and 35.30% for shoot and 57.09 and 34.48% for root compared to pot treated with 100 mg kg-1 lead. Cow dung remediated lead concentration by 48.85, 65.00 and 62.00% for grain, shoot and root, respectively. J. Biodivers. Conserv. Bioresour. Manag. 2019, 5(2): 83-92

Effect of Metals on the Biomass Production Kinetics of Freshwater Copepods

1980 ◽  
Vol 37 (4) ◽  
pp. 567-575 ◽  
Author(s):  
U. Borgmann ◽  
R. Cove ◽  
C. Loveridge
Keyword(s):  
Biomass Production ◽  
Lead Toxicity ◽  
Dry Weight ◽  
Mortality Rates ◽  
Natural Food ◽  
Mathematical Relationship ◽  
Toxic Concentration ◽  
Natural Assemblage ◽  
Freshwater Copepods ◽  
Kinetics Of

The effects of cadmium, copper, mercury, lead, and arsenic on the growth and mortality rates of a natural assemblage of copepods using natural food and water were determined. A seasonal cycle in toxicity was observed for all the metals except arsenic. Lead toxicity appeared to be related to the ash-free dry weight of the seston, but the reason for the variation in toxicity of cadmium, copper, and mercury remain unknown. The chronic toxicity of some metals differs much less between copepods and daphnids than does acute toxicity. The mathematical relationship between growth and mortality rates and metal concentration is discussed and a technique for calculating a sublethally toxic concentration is described.Key words: copepods, heavy metals, biomass production, cadmium, copper, mercury, lead, arsenic, toxicity

Ecology and production of Nebalia sp. (Crustacea : Leptostraca) in a shallow-water seagrass community.

1991 ◽  
Vol 42 (1) ◽  
pp. 53 ◽  
Author(s):  
SF Rainer ◽  
P Unsworth
Keyword(s):  
Growth Rate ◽  
Mortality Rate ◽  
Secondary Production ◽  
Dry Weight ◽  
Seagrass Beds ◽  
Seagrass Meadows ◽  
Seagrass Community ◽  
Field Samples ◽  
Fish Predators ◽  
Nocturnal Fish

Nebalia sp. is an abundant epifaunal crustacean in seagrass meadows at Seven Mile Beach, Western Australia, in water temperatures of 16-27�C. Its maximum length is 6.0-6.4 mm; females generally reach maturity when 4 mm long and males when 5 mm long. They breed throughout the year, and juveniles comprised 94% of animals sampled (n = 880). Males comprised only 11% of mature animals in field samples, compared with 40% in field chambers and 67% in the stomachs of nocturnal fish predators. Abundance during the year reflected changes in growth rate (0.050-0.088 mm day-1), mortality rate (0.020-0.069 day-1) and life span (49-102 days). The annual production of Nebalia sp. in seagrass meadows was estimated at 5.8 g ash-free dry weight (AFDW) m-2, with a corresponding P :B (production:biomass) ratio of 22.5. Predation is probably the main source of mortality at times of high density of Nebalia sp., and at least three significant fish predators on Nebalia sp. were found. Together with Nebalia sp., small crustaceans with high P:B ratios may have a significant role in secondary production in the seagrass beds at Seven Mile Beach.

scholarly journals Effects of Lead on Growth and Mineral Nutrition of Wheat (Triticum Aestivum L.) As Influenced by Manure and Lime

2021 ◽  
Vol 6 (2) ◽  
pp. 69-76
Author(s):  
P Jasmin ◽  
AS Chamon ◽  
MN Mondol ◽  
SM Ullah
Keyword(s):  
Triticum Aestivum ◽  
Mineral Nutrition ◽  
Lead Concentration ◽  
Poultry Litter ◽  
Dry Weight ◽  
Triticum Aestivum L ◽  
Organic Manure ◽  
Lead Uptake ◽  
Maximum Reduction ◽  
Four Levels

A pot experiment was conducted to evaluate the effects of four levels of lead (50, 100, 150 and 200 mg/kg) treatment on wheat (Triticum aestivum L.) and its amelioration by cowdung, poultry litter and lime. The lengths, fresh and dry weights of shoot and root decreased with increasing level of lead as well as the macronutrients compared to the control. The maximum reduction was observed in the pots treated with 200 mg/kg lead. The highest reduction in macronutrient content was also observed in 200 mg/kg Pb treated pot whereas N, P, K, Ca and Mg concentration was reduced by 0.41, 0.019, 1.15, 0.38 and 0.071% for shoot and 0.512, 0.071, 0.17, 0.51 and 0.122% for root, respectively. Lead concentration in roots and shoots increased with increasing level of lead treatment compared to the control. Cowdung was shown to be most effective, followed by poultry litter and lime. This particular organic manure had considerably greater decreasing impacts in lead uptake by wheat crops. Cowdung treated pots increased fresh and dry weight by 14.56 and 13.28% for grain, 7.58 and 7.08% for shoot and 2.41 and 2.06% for root compared to pot treated with 100 mg/kg lead. J. Biodivers. Conserv. Bioresour. Manag. 2020, 6(2): 69-76

Fourteen percent mortality rate in catheter-drainage series: setting the record straight.

1999 ◽  
Vol 172 (1) ◽  
pp. 241-242
Author(s):  
R E Lambiase ◽  
J J Cronan
Keyword(s):  
Mortality Rate ◽  
Catheter Drainage ◽  
Percent Mortality

scholarly journals Overexpression of vesicle-associated membrane protein PttVAP27-17 as a tool to improve biomass production and the overall saccharification yields in Populus trees

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Madhavi Latha Gandla ◽  
Niklas Mähler ◽  
Sacha Escamez ◽  
Tomas Skotare ◽  
Ogonna Obudulu ◽  
...  
Keyword(s):  
Membrane Protein ◽  
Biomass Production ◽  
Enzymatic Saccharification ◽  
Dry Weight ◽  
Populus Tremula ◽  
Transgenic Trees ◽  
Wild Type ◽  
Glucose Yield ◽  
Transgenic Lines ◽  
Wild Type Control

Abstract Background Bioconversion of wood into bioproducts and biofuels is hindered by the recalcitrance of woody raw material to bioprocesses such as enzymatic saccharification. Targeted modification of the chemical composition of the feedstock can improve saccharification but this gain is often abrogated by concomitant reduction in tree growth. Results In this study, we report on transgenic hybrid aspen (Populus tremula × tremuloides) lines that showed potential to increase biomass production both in the greenhouse and after 5 years of growth in the field. The transgenic lines carried an overexpression construct for Populus tremula × tremuloides vesicle-associated membrane protein (VAMP)-associated protein PttVAP27-17 that was selected from a gene-mining program for novel regulators of wood formation. Analytical-scale enzymatic saccharification without any pretreatment revealed for all greenhouse-grown transgenic lines, compared to the wild type, a 20–44% increase in the glucose yield per dry weight after enzymatic saccharification, even though it was statistically significant only for one line. The glucose yield after enzymatic saccharification with a prior hydrothermal pretreatment step with sulfuric acid was not increased in the greenhouse-grown transgenic trees on a dry-weight basis, but increased by 26–50% when calculated on a whole biomass basis in comparison to the wild-type control. Tendencies to increased glucose yields by up to 24% were present on a whole tree biomass basis after acidic pretreatment and enzymatic saccharification also in the transgenic trees grown for 5 years on the field when compared to the wild-type control. Conclusions The results demonstrate the usefulness of gene-mining programs to identify novel genes with the potential to improve biofuel production in tree biotechnology programs. Furthermore, multi-omic analyses, including transcriptomic, proteomic and metabolomic analyses, performed here provide a toolbox for future studies on the function of VAP27 proteins in plants.

scholarly journals A Cyanobacteria-Based Biofilm System for Advanced Brewery Wastewater Treatment

2020 ◽  
Vol 11 (1) ◽  
pp. 174
Author(s):  
Konstantinos P. Papadopoulos ◽  
Christina N. Economou ◽  
Athanasia G. Tekerlekopoulou ◽  
Dimitris V. Vayenas
Keyword(s):  
Wastewater Treatment ◽  
Biomass Production ◽  
Low Cost ◽  
Oxygen Demand ◽  
Dry Weight ◽  
Surface Hydrophobicity ◽  
Reactor Performance ◽  
Brewery Wastewater ◽  
Kjeldahl Nitrogen ◽  
Supporting Materials

Algal/cyanobacterial biofilm photobioreactors provide an alternative technology to conventional photosynthetic systems for wastewater treatment based on high biomass production and easy biomass harvesting at low cost. This study introduces a novel cyanobacteria-based biofilm photobioreactor and assesses its performance in post-treatment of brewery wastewater and biomass production. Two different supporting materials (glass/polyurethane) were tested to investigate the effect of surface hydrophobicity on biomass attachment and overall reactor performance. The reactor exhibited high removal efficiency (over 65%) of the wastewater’s pollutants (chemical oxygen demand, nitrate, nitrite, ammonium, orthophosphate, and total Kjeldahl nitrogen), while biomass per reactor surface reached 13.1 and 12.8 g·m−2 corresponding to 406 and 392 mg·L−1 for glass and polyurethane, respectively, after 15 days of cultivation. The hydrophilic glass surface favored initial biomass adhesion, although eventually both materials yielded complete biomass attachment, highlighting that cell-to-cell interactions are the dominant adhesion mechanism in mature biofilms. It was also found that the biofilm accumulated up to 61% of its dry weight in carbohydrates at the end of cultivation, thus making the produced biomass a suitable feedstock for bioethanol production.

EFFECTS OF TEMPERATURE ON RATE AND DURATION OF KERNEL DRY MATTER ACCUMULATION OF MAIZE

1988 ◽  
Vol 68 (4) ◽  
pp. 935-940 ◽  
Author(s):  
M. TOLLENAAR ◽  
T. W. BRUULSEMA
Keyword(s):  
Growth Rate ◽  
Zea Mays ◽  
Dry Matter ◽  
Zea Mays L ◽  
Dry Weight ◽  
Controlled Environment ◽  
Dry Matter Accumulation ◽  
Linear Kernel ◽  
Effects Of Temperature ◽  
Kernel Growth

The response of rate and duration of kernel dry matter accumulation to temperatures in the range 10–25 °C was studied for two maize (Zea mays L.) hybrids grown under controlled-environment conditions. Kernel growth rates during the period of linear kernel growth increased linearly with temperature (b = 0.3 mg kernel−1 d−1 °C−1). Kernel dry weight at physiological maturity varied little among temperature treatments because the increase in kernel growth rate with increase in temperature was associated with a decline in the duration of kernel growth proportional to the increase in kernel growth rate.Key words: Zea mays L, period of linear kernel dry matter accumulation, controlled-environment conditions, kernel growth rate

pH-Induced Changes in Blood Lead of Lead-Exposed Rainbow Trout (Salmo gairdneri)

1978 ◽  
Vol 35 (4) ◽  
pp. 437-445 ◽  
Author(s):  
Peter V. Hodson ◽  
Beverly R. Blunt ◽  
Douglas J. Spry
Keyword(s):  
Rainbow Trout ◽  
Lead Toxicity ◽  
Blood Lead ◽  
Salmo Gairdneri ◽  
Lead Uptake ◽  
Exposure System ◽  
Test Water ◽  
Induced Changes ◽  
Inorganic Constituents ◽  
Uptake And Release

Blood of juvenile rainbow trout (Salmo gairdneri) exposed to lead in water showed increasing lead concentrations as pH of the test water decreased from 10.0 to 6.0. A decrease in pH by 1.0 unit from any reference pH resulted in an increase of blood lead by a factor of 2.1. Since sublethal lead toxicity is related to uptake, these results suggest that toxicity increases as pH decreases. Control experiments indicated that reactions of lead with inorganic constituents of the test water were complete within 3 h and that blood lead was at equilibrium with water lead within 48 h. Therefore, at the time of blood sampling in the pH experiment, both lead complexation processes in the exposure system, plus lead uptake and release from the blood, were at equilibrium. Key words: pH, lead, toxicity, fish, Salmo, blood, equilibrium.

The Energy-Sources in Ontogenesis

1927 ◽  
Vol 5 (1) ◽  
pp. 27-42
Author(s):  
JOSEPH NEEDHAM
Keyword(s):  
Growth Rate ◽  
Oxygen Consumption ◽  
Building Materials ◽  
Calorific Value ◽  
Dry Weight ◽  
Energy Sources ◽  
Chemical Analyses ◽  
Inorganic Substance ◽  
Absorption Intensity ◽  
Dry Substance

1. The percentage growth-rate curves for carbohydrate and protein in the chick enbryo have been determined and compared with those already in the literature for the percentage growth-rates of the whole embryo, the dry substance, the fat, and the calorific value. 2. The composition of the embryo in gm. per cent, of dry weight has been calculated and an ontogenetic succession of carbohydrate, protein, and fat, has been brought to light. These three cell-constituents are at their highest levels in the embryo at 4, 11 and 20 days of incubation respectively. This may be correlated with the succession of maximum intensities of combustion, which have the same order (about 5,8.5 and about 18 days). 3. By comparing the curves for absorption-intensity with those representing the constitution of the embryo, it has been possible to trace the passage of building-materials from the yolk and white into the embryo and to analyse still further the movements of the fat and carbohydrate fractions. 4. The concentration of the carbohydrate and protein in the water of the embryonic body has been calculated and compared with a curve already in existence for fat. 5. The curve for intensity of absorption of total foodstuff has been calculated from the results of chemical analyses. It agrees as well as can be expected at present with that calculated from the oxygen consumption and the increase of dry substance in the embryo. 6. The ratio Carbohydrate : Protein decreases during development, thus falling into line with the ratios Water : Solid, Inorganic Substance : Organic Substance, and Protein : Fat. Certain speculations arising out of these facts are discussed. 7. There is a relation of simultaneity between the combustion of carbohydrate, protein, and fat, and the part these types of molecule play in the constitution of the whole embryo.

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