Iron In Lake Water Research Articles

The ecological-hydrochemical condition of the Ryazan Meshchera lakes

Identifies the main hydro-chemical parameters of some lakes of the Ryazan Meshchera, including lakes Laskowski, located in the immediate vicinity of the centre. All lakes are of glacial origin and were formed in specific environmental and geochemical conditions of Polesie landscapes. They are characterized by widespread fluvioglacial and ancient alluvial sand deposits, a kind of combination of coniferous forests with marshy areas, a relatively small anthropogenic load. The research established that extremely low TDS water of all lakes, and respectively detected very small concentrations of major macro - and micronutrients. Against this background, a large presence of iron in lake water, which is related to the geochemical background. The signs of pollution, including domestic sewage, in the studied lakes was not detected.

Growth Characteristics of the Musty Odor Producing Alga, Oscillatoria tenuis

The production of 2-methylisoborneol (MIB) by Oscillatoriatenuis Agardh often causes taste and odor problems in tap water supplied from Lake Biwa. In order to understand growth characteristics of O. tenuis, the alga was cultured under several different conditions. The maximum biomass observed in culture was about 2000 filaments/ml, whereas the standing crop measured in the lake was as low as 32 filaments/ml. The optimum temperature and pH were 25-30 C and 8-9, respectively. The concentrations of nitrogen and phosphorus which were optimum for growth in the medium were 0.31 mg/l and 0.08 mg/l and above, respectively. The concentrations of these elements in the lake were almost equal to those resulting in optimum growth. Growth of the alga was suppressed when the alga was grown in the culture medium from which chelated iron was removed. The total concentration of iron in lake water was sufficient for the algal growth; however, the concentration of soluble iron, which is available for the alga, was lower than in CT-medium. Addition of 0.03 mg/l EDTA to lake water promoted the algal growth invitro, while 3 mg/l EDTA suppressed the growth. The difference between growth under culture conditions and that in the lake may be due to the difference in the concentration of soluble iron.

Supply of iron and manganese to an anoxic lake basin

In seasonally anoxic lakes, the dynamic cycling of iron and manganese makes possible the study of geochemical cycling and processes of mineral formation, while the rapid lake processes may be a model for the analogous but slower oceanic processes. We have now measured concentration–depth profiles for iron and manganese to assess the flux of these elements from the sediments. The seasonal accumulation of iron in lake water can be accounted for by supply from the sediment, but the manganese profiles suggest that the major source of manganese is dissolution from particular material sedimenting through the water column.

Comparison of differential pulse and D.C. sampled polarography for the determination of ferrous and manganous ions in lake water

Differential pulse and d.c. sampled polarography have been used to investigated the reduction of ferrous and manganous ions from both hypolimnetic lake water and a synthetic solution of comparable alkalinity and ionic strength. Generally d.c. sampled measurements gave linear calibration curves which were suitable for analytical use, while the differential pulse technique produced non-linear curves. This was explained by an iR drop effect operating in the electrochemical cell. Ferrous iron in lake water proved exceptional because the differential pulse calibration curve was linear. For the concentration range considered (2×10−6−10−4 M) d.c. sampled polarography is recommended for the determination of manganous ion and differential pulse for ferrous ion. It has been demonstrated that each water system must be investigated individually before deciding on the most suitable electroanalytical technique.

Comparison of differential pulse and D.C. sampled polarography for the determination of ferrous and manganous ions in lake water

Differential pulse and d.c. sampled polarography have been used to investigated the reduction of ferrous and manganous ions from both hypolimnetic lake water and a synthetic solution of comparable alkalinity and ionic strength. Generally d.c. sampled measurements gave linear calibration curves which were suitable for analytical use, while the differential pulse technique produced non-linear curves. This was explained by an iR drop effect operating in the electrochemical cell. Ferrous iron in lake water proved exceptional because the differential pulse calibration curve was linear. For the concentration range considered (2×10 −6−10 −4 M) d.c. sampled polarography is recommended for the determination of manganous ion and differential pulse for ferrous ion. It has been demonstrated that each water system must be investigated individually before deciding on the most suitable electroanalytical technique.

An acid-free bathophenanthroline method for measuring dissolved ferrous iron in lake water

An acid-free solvent extraction technique, using bathophenanthroline, is proposed for measuring dissolved ferrous iron in filtered lake water. Omission of HCl from the reagents eliminates the influence of acid and light on ferrous iron determinations. The effects of membrane filtration and ferric-bathophenanthroline interference on absorbance at 533 mμ are discussed.

THE INFLUENCE OF LIGHT AND ACID ON THE MEASUREMENT OF FERROUS IRON IN LAKE WATER

A modified bathophenanthroline procedure for the determination of ferrous iron in lake water is described. Data on recoveries of Fe2+ from lake water and Fe3+ standard solutions are given. The recovery of Fe2+ is affected by the HCl concentration and by exposure of the sample to sunlight.