Ionic Regulation of the Baltic and Fresh-Water Races of the Isopod Mesidotea (Saduria) Entomon (L.)

1968 ◽  
Vol 48 (1) ◽  
pp. 141-158 ◽  
Author(s):  
P. C. CROGHAN ◽  
A. P. M. LOCKWOOD
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Sodium Concentration ◽  
Relative Volume ◽  
Ice Age ◽  
Ionic Regulation ◽  
Sodium Influx ◽  
Active Uptake ◽  
Concentrated Solution ◽  
The Baltic

1. The isopod Mesidotea entomon has colonized the Baltic and certain Swedish lakes since the end of the last Ice Age. 2. The ionic regulation of Baltic animals and fresh-water animals (L. Mälaren) has been compared. 3. It has been possible to adapt Baltic animals to very dilute media, but 5% Askö sea water (5.5 mM/l. Na) appears to be the limit of adaptation. The haemolymph sodium concentration of Baltic animals from the very dilute media was considerably lowered. 4. The haemolymph sodium concentration in Mälaren animals is high (250 mM/l. Na) and comparable with that in Baltic animals in much more concentrated solution. The haemolymph ionic ratios of the Baltic and freshwater animals are similar. The Cl:Na ratio rises slightly in the more concentrated haemolymph samples. 5. From the concentration of ions in the haemolymph and in the total body water, the relative volume of the haemolymph was calculated. Mälaren animals appear to have a much larger haemolymph volume. 6. The permeability of the animals was determined from the rate of loss of sodium into de-ionized water. The permeability of the Mälaren animals is considerably reduced compared to the Baltic animals. Permeability is not related to the medium to which the animals had been adapted. 7. The sodium influx was determined using 22Na. The rate of active uptake was calculated from this. The maximal rate of active uptake was similar in Baltic and Mälaren animals. The sodium concentration of the medium at which active uptake was half maximum (KM) was considerably lower in Malaren animals than in Baltic animals. 8. The evolution of Mesidotea as a fresh-water animal is interpreted as a result of a reduction in permeability of the external surfaces to NaCl and an increase in the affinity of the active transport mechanism enabling the animal to maintain the haemolymph NaCl concentration in a steady state in fresh water.

scholarly journals The Chloride Regulation of the Brackish and Fresh-Water Races of Mesidotea Entomon (L.)

1957 ◽  
Vol 34 (2) ◽  
pp. 253-258 ◽  
Author(s):  
A. P. M. LOCKWOOD ◽  
P. C. CROGHAN
Keyword(s):  
Fresh Water ◽  
Brackish Water ◽  
Sea Water ◽  
Chloride Concentration ◽  
Ice Age ◽  
General Level ◽  
Last Ice Age ◽  
The Baltic ◽  
Chloride Regulation

1. Mesidotea entomon (L.) is found in the Baltic and in certain fresh-water lakes in Sweden. It is believed that colonization of fresh water in this region has taken place since the last Ice-age. 2. In the present work animals from brackish and fresh-water habitats have been compared both in respect of the concentration of chloride in their haemolymph and of their ability to survive in media of various salinities. 3. Both fresh-water and Baltic animals have been found able to survive in Plymouth sea water, the concentration of chloride in their haemolymph being close to the concentration of chloride in this medium. 4. Baltic animals could not be acclimatized to fresh water. 5. Animals from both habitats have the same general level of chloride concentration in their haemolymph when acclimatized to dilute sea water. 6. These results are discussed in relation to the evolution of a fresh-water race from a brackish-water race.

Erratum

1970 ◽  
Vol 52 (2) ◽  
pp. 494-494
Keyword(s):  
Fresh Water ◽  
Sodium Transport ◽  
Sodium Concentration ◽  
Sodium Influx ◽  
Lampetra Planeri

MORRIS, R. & BULL, J. M. Studies on fresh water osmoregulation in the Ammocoete larvae of Lampetra planeri Bloch. III. The effect of external and internal sodium concentration on sodium transport. J. Exp. Biol. 52, 2, pp. 275-290. Page 287. Figure 5. For ‘Sodium influx (µM/gm./hr.)’ read ‘Sodium influx (µM/3gm./hr.)’

Sodium Regulation and Adaptation to Fresh Water in Gammarid Crustaceans

1968 ◽  
Vol 48 (2) ◽  
pp. 359-380
Author(s):  
D. W. SUTCLIFFE
Keyword(s):  
Body Weight ◽  
Fresh Water ◽  
Body Surface ◽  
Sea Water ◽  
Sodium Concentration ◽  
The Body ◽  
Outward Diffusion ◽  
Gammarus Zaddachi ◽  
Freshwater Habitats ◽  
Sodium Regulation

1. Sodium uptake and loss rates are given for three gammarids acclimatized to media ranging from fresh water to undiluted sea water. 2. In Gammarus zaddachi and G. tigrinus the sodium transporting system at the body surface is half-saturated at an external concentration of about 1 mM/l. and fully saturated at about 10 mM/l. sodium. In Marinogammarus finmarchicus the respective concentrations are six to ten times higher. 3. M. finmarchicus is more permeable to water and salts than G. zaddachi and G. tigrinus. Estimated urine flow rates were equivalent to 6.5% body weight/hr./ osmole gradient at 10°C. in M. finmarchicus and 2.8% body weight/hr./osmole gradient in G. zaddachi. The permeability of the body surface to outward diffusion of sodium was four times higher in M. finmarchicus, but sodium losses across the body surface represent at least 50% of the total losses in both M. finmarchicus and G. zaddachi. 4. Calculations suggest that G. zaddachi produces urine slightly hypotonic to the blood when acclimatized to the range 20% down to 2% sea water. In fresh water the urine sodium concentration is reduced to a very low level. 5. The process of adaptation to fresh water in gammarid crustaceans is illustrated with reference to a series of species from marine, brackish and freshwater habitats.

Sodium Regulation in the Amphipod Gammarus Duebeni Lilljeborg form Freshwater Localities in Ireland

1968 ◽  
Vol 48 (2) ◽  
pp. 339-358
Author(s):  
D. W. SUTCLIFFE ◽  
J. SHAW
Keyword(s):  
Fresh Water ◽  
Loss Rate ◽  
Sea Water ◽  
Detailed Comparison ◽  
Urine Concentration ◽  
Sodium Influx ◽  
Fresh Waters ◽  
Low Sodium ◽  
Characteristic Features ◽  
Sodium Regulation

1. A quantitative study of sodium influx and loss was made on populations of Gammarus duebeni obtained from four freshwater localities in Ireland. 2. Characteristic features of sodium regulation in animals from the four localities were as follows, (a) The sodium influx increases gradually with increasing external sodium concentrations, but a maximum (saturation) level is abruptly reached at an external concentration of 1-2 mM/l. and the transporting system is half saturated at about 0.5 mM/l. sodium, (b) Over the range of sodium concentrations found in fresh waters a low rate of sodium uptake is sufficient to balance sodium losses at concentrations down to between 0.5 and 0.25 mM/l. At lower concentrations the influx is increased and the loss rate is reduced. (c) Calculations suggest that hypotonic urine containing approximately 40 mM/l sodium is produced at external concentrations ranging from fresh water to 40 % sea water. At external concentrations below 0.25 mM/l. sodium the urine concentration is probably reduced to well below 40 mM/l. sodium. 3. A detailed comparison is made of sodium regulation at external concentrations ranging between 0.07 and 1 mM/l. sodium in G. duebeni from fresh water in Ireland and from fresh water and brackish water in Britain. It is suggested that G. duebeni in Ireland constitutes a distinct physiological race adapted for living in fresh waters with relatively low sodium concentrations.

scholarly journals Density and Absolute Salinity of the Baltic Sea 2006–2009

2009 ◽  
Vol 6 (2) ◽  
pp. 1757-1817 ◽  
Author(s):  
R. Feistel ◽  
S. Weinreben ◽  
H. Wolf ◽  
S. Seitz ◽  
P. Spitzer ◽  
...  
Keyword(s):  
Equation Of State ◽  
Baltic Sea ◽  
Fresh Water ◽  
Decadal Variability ◽  
Sea Water ◽  
Large Area ◽  
The Baltic Sea ◽  
Sulphate Content ◽  
Density Anomaly ◽  
The Baltic

Abstract. The brackish water of the Baltic Sea is a mixture of ocean water from the Atlantic/North Sea with fresh water from various rivers draining a large area of lowlands and mountain ranges. The evaporation-precipitation balance results in an additional but minor excess of fresh water. The rivers carry different loads of salts washed out of the ground, in particular calcium carbonate, which cause a composition anomaly of the salt dissolved in the Baltic Sea in comparison to Standard Seawater. Directly measured seawater density shows a related anomaly when compared to the density computed from the equation of state as a function of Practical Salinity, temperature and pressure. Samples collected from different regions of the Baltic Sea during 2006–2009 were analysed for their density anomaly. The results obtained for the river load deviate significantly from similar measurements carried out forty years ago; the reasons for this decadal variability are not yet fully understood. An empirical formula is derived which estimates Absolute from Practical Salinity of Baltic Sea water, to be used in conjunction with the new Thermodynamic Equation of Seawater 2010 (TEOS-10), endorsed by IOC/UNESCO in June 2009 as the substitute for the 1980 International Equation of State, EOS-80. Our routine measurements of the samples were accompanied by studies of additional selected properties which are reported here: conductivity, density, chloride, bromide and sulphate content, total CO2 and alkalinity.

scholarly journals Density and Absolute Salinity of the Baltic Sea 2006–2009

Ocean Science ◽  
2010 ◽  
Vol 6 (1) ◽  
pp. 3-24 ◽  
Author(s):  
R. Feistel ◽  
S. Weinreben ◽  
H. Wolf ◽  
S. Seitz ◽  
P. Spitzer ◽  
...  
Keyword(s):  
Equation Of State ◽  
Baltic Sea ◽  
Fresh Water ◽  
Decadal Variability ◽  
Sea Water ◽  
Large Area ◽  
The Baltic Sea ◽  
Sulphate Content ◽  
Density Anomaly ◽  
The Baltic

Abstract. The brackish water of the Baltic Sea is a mixture of ocean water from the Atlantic/North Sea with fresh water from various rivers draining a large area of lowlands and mountain ranges. The evaporation-precipitation balance results in an additional but minor excess of fresh water. The rivers carry different loads of salts washed out of the ground, in particular calcium carbonate, which cause a composition anomaly of the salt dissolved in the Baltic Sea in comparison to Standard Seawater. Directly measured seawater density shows a related anomaly when compared to the density computed from the equation of state as a function of Practical Salinity, temperature and pressure. Samples collected from different regions of the Baltic Sea during 2006–2009 were analysed for their density anomaly. The results obtained for the river load deviate significantly from similar measurements carried out forty years ago; the reasons for this decadal variability are not yet fully understood. An empirical formula is derived which estimates Absolute from Practical Salinity of Baltic Sea water, to be used in conjunction with the new Thermodynamic Equation of Seawater 2010 (TEOS-10), endorsed by IOC/UNESCO in June 2009 as the substitute for the 1980 International Equation of State, EOS-80. Our routine measurements of the samples were accompanied by studies of additional selected properties which are reported here: conductivity, density, chloride, bromide and sulphate content, total CO2 and alkalinity.

Preliminary Observations on the Ionic Regulation of the Arctic Char Salvelinus Alpinus

1971 ◽  
Vol 55 (1) ◽  
pp. 213-222
Author(s):  
R. A. ROBERTS
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Potassium Concentration ◽  
Salvelinus Alpinus ◽  
Sodium Concentration ◽  
Sodium Content ◽  
Arctic Char ◽  
The Arctic ◽  
High Degree ◽  
Total Sodium

1. The degree of euryhalinity in a fresh-water resident population of the arctic char, Salvelinus alpinus, has been determined. 2. Although isolated in fresh water for c. 10000-12000 years these fish still show a high degree of salinity tolerance characteristic of their ancestral stock, but this is variably developed in individuals. 3. In fresh water, blood sodium concentration is regulated at 150 mM/l and chloride at 130 mM/l. These increase to 233 and 218 mm/l respectively in sea water. 4. Fish in sea water show a large increase in muscle sodium, although the potassium concentration is only slightly higher than that maintained in fresh water. The total sodium content of the fish reflects the increase observed in the intracellular and extracellular compartments. 5. The rate of sodium turnover in sea-water-adapted fish is some ten times higher than in fresh-water-adapted fish, although it is significantly lower than that observed in most sea-water-adapted teleosts.

Sodium Regulation in the Fresh-Water Amphipod, Gammarus Pulex (L.)

1967 ◽  
Vol 46 (3) ◽  
pp. 499-518
Author(s):  
D. W. SUTCLIFFE
Keyword(s):  
Fresh Water ◽  
Body Surface ◽  
Loss Rate ◽  
Sodium Concentration ◽  
The Body ◽  
Uptake Mechanism ◽  
Sodium Influx ◽  
Sodium Uptake ◽  
Sodium Loss ◽  
Total Sodium

1. Sodium influx and loss rates in Gammarus pulex were measured at constant temperatures. The sodium loss rate was immediately influenced by a change in temperature, with a Q10 of 1.5 to 2.0 at temperatures between 0.3 and 21.5° C. The sodium influx rate is apparently influenced in the same way. 2. The sodium uptake mechanism in G. pulex from three localities was half-saturated at an external concentration of 0.10-0.15 mM/l. sodium. 3. The total sodium loss rate remained approximately constant in animals acclimatized to the range of external concentrations from 2 to about 0.2 mM/l. sodium. 18% of the sodium was lost in urine with a sodium concentration estimated at 30-50 mM/l. The remainder of the sodium loss was due to diffusion across the body surface. 4. In animals acclimatized to concentrations below about 0.2 mM/l. sodium the sodium loss rate was reduced, due to (a) a lower diffusion rate following a fall in the blood sodium concentration, and (b) the elaboration of a more dilute urine. 5. There was a very close association between changes in the blood sodium concentration, the elaboration of a very dilute urine, and the rate of sodium uptake at the body surface. The results indicate that a fall in the blood sodium concentration leads to simultaneous activation of the sodium uptake mechanisms at the body surface and in the antennary glands. 6. It is estimated that, by producing a dilute urine, total sodium uptake in G. pulex is shared equally between the renal uptake mechanism and the mechanism situated at the body surface. 7. In sea-water media G. pulex drinks and expels fluid from the gut. In a medium slightly hyperosmotic to the normal blood concentration the amount imbibed was equal to the normal rate of urine flow when in fresh water.

scholarly journals Biodegradation of poly(ε-caprolactone) in natural water environments

2017 ◽  
Vol 19 (1) ◽  
pp. 120-126 ◽  
Author(s):  
Aleksandra Heimowska ◽  
Magda Morawska ◽  
Anita Bocho-Janiszewska
Keyword(s):  
Weight Loss ◽  
Surface Morphology ◽  
Baltic Sea ◽  
Fresh Water ◽  
Sea Water ◽  
Characteristic Parameters ◽  
The Baltic Sea ◽  
Loss Of Weight ◽  
Water Pond ◽  
The Baltic

AbstractThe environmental degradation of poly(ε-caprolactone)[PCL] in natural fresh water (pond) and in The Baltic Sea is presented in this paper. The characteristic parameters of both environments were measured during experiment and their influence on the biodegradation of the samples was discussed. The loss of weight and changes of surface morphology of polymer samples were tested during the period of incubation. The poly(ε-caprolactone) was more biodegradable in natural sea water than in pond. PCL samples were completely assimilated over the period of six weeks incubation in The Baltic Sea water, but after forty two weeks incubation in natural fresh water the polymer weight loss was about 39%. The results have confirmed that the investigated polymers are susceptible to an enzymatic attack of microorganisms, but their activity depends on environments.

scholarly journals Sodium and Water Balance in the Cichlid Teleost, Tilapia Mossambica

1967 ◽  
Vol 47 (3) ◽  
pp. 461-470 ◽  
Author(s):  
W. T. W. POTTS ◽  
M. A. FOSTER ◽  
P. P. RUDY ◽  
G. PARRY HOWELLS
Keyword(s):  
Water Balance ◽  
Fresh Water ◽  
Sea Water ◽  
Tritiated Water ◽  
Sodium Influx ◽  
Water Drinking ◽  
Body Sodium ◽  
Total Body ◽  
Sodium And Water Balance ◽  
Total Sodium

1. The total body sodium increases from 45.9 µM/g. fish in fresh water to 59.9 µM/g. fish in 200 % sea water. 2. The rate of exchange of sodium increases from 2 µM/g./hr. in fresh water to 60 µM/g./hr. in 100% sea water. 3. The rate of drinking increases from 0.26%/hr. fresh water to 1.6%/hr. in 400% sea water. Even in 200% sea water drinking accounts for only a quarter of the total sodium influx. 4. The permeability to water, as measured by tritiated water, is highest in fresh water and lowest in 200% sea water. The permeabilities to water measured in this way are consistent with the drinking rates determined in sea water and 200% sea water.

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