Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 91 - 118 of 118

Full-Text Articles in Life Sciences

Zinc Adsorption By Sterilized And Non-Sterilized Soil In The Presence Of Citrate And Catechol, P. Chairidchai, G. S.P. Ritchie Feb 1993

Zinc Adsorption By Sterilized And Non-Sterilized Soil In The Presence Of Citrate And Catechol, P. Chairidchai, G. S.P. Ritchie

Food Science and Nutrition

The effect of organic ligands on zinc (Zn) adsorption in the rhizosphere may be influenced by microbial activity depleting the concentration of the ligand over time. Zinc adsorption by sterile and non-sterile lateritic soil was measured by shaking the soils with Zn solutions at a soil-liquid ratio of 1: 5 for five periods of time ranging from 17-480 h. The concentrations of Zn and the ligands were determined after the selected times. The speciation of Zn was then estimated. Changes in Zn adsorption with time in the presence of organic ligands were due to changes in pH and Zn complexation …


Al Toxicity Of Wheat Grown In Acidic Subsoils In Relation To Soil Solution Properties And Exchangeable Cations, S. J. Carr, G. S.P. Ritchie Jan 1993

Al Toxicity Of Wheat Grown In Acidic Subsoils In Relation To Soil Solution Properties And Exchangeable Cations, S. J. Carr, G. S.P. Ritchie

Food Science and Nutrition

Toxic concentrations of soluble A1 in the subsoil decrease the yield of wheat grown on many yellow earths in the eastern wheatbelt of Western Australia. In our previous research (Carr et al. 1991), we observed variable plant response to high concentrations of soluble Al in subsoils of yellow earths in different regions of the wheatbelt. Environmental conditions (e.g. water supply) and/or an unidentified soil mitigating factor may have contributed to the variable plant response to soluble Al in some of the regions studied.
We collected ten soils from four regions of the eastern wheatbelt of Western Australia. In a glasshouse …


The Influence Of Ph On The Forms Of Cadmium In Four West Australian Soils, S. S. Mann, G. S.P. Ritchie Jan 1993

The Influence Of Ph On The Forms Of Cadmium In Four West Australian Soils, S. S. Mann, G. S.P. Ritchie

Food Science and Nutrition

The forms of cadmium in soils affect its uptake by plants and hence its potential toxicity to animals and humans. We studied the effect of pH on the forms of native and added Cd in four West Australian soils which differed in their clay, hydrous oxide and organic matter content. The forms of Cd were extracted sequentially by KCl, BaCl2, NaOCl, ammonium oxalate and concentrated acids.
The majority of Cd applied to a sandy soil was found in the soluble (KCl) and the exchangeable (BaCl2) forms at all pH values. In the siliceous sand, the proportion …


Phosphorus Retention And Release From Sandy Soils Of The Peel-Harvey Catchment, G. S.P. Ritchie, D. M. Weaver Jan 1993

Phosphorus Retention And Release From Sandy Soils Of The Peel-Harvey Catchment, G. S.P. Ritchie, D. M. Weaver

Food Science and Nutrition

In order to manage phosphorus (P) losses from soils to waterbodies, knowledge of the mechanisms through which P is retained or released from the soil is essential. Sandy soils of the Peel-Harvey catchment (Western Australia) were subjected to a range of environmental and management factors in the laboratory and field in order to gain an understanding of the mechanisms that affect the magnitude of P losses. Sandy soils accumulated P, despite having little sorption capacity, and this accumulation could be monitored by measuring an acid-extractable fraction. The potential, short-term P loss could be estimated by determination of water-soluble soil solution …


H+/Oh- Excretion And Nutrient Uptake In Upper And Lower Parts Of Lupin (Lupinus Angustifolius L.) Root Systems, S. P. Loss, A. D. Robson, G. S.P. Ritchie Jan 1993

H+/Oh- Excretion And Nutrient Uptake In Upper And Lower Parts Of Lupin (Lupinus Angustifolius L.) Root Systems, S. P. Loss, A. D. Robson, G. S.P. Ritchie

Food Science and Nutrition

The cultivation of narrow-leafed lupins (Lupinus angustifolius L.) increase rates of subsoil acidification, and this is thought to be partly related to their pattern of nutrient uptake and H+/OH- excretion. The main hypothesis of this study was that H+ and OH- excretion is not distributed evenly over the entire length of the root system but is limited to zones where excess cation or anion uptake occur. Seedlings of nodulated lupins were grown in solution culture using vertically split pots that allowed the upper and lower zones of the root system to be supplied with …


The Long-Term Fate Of Copper Fertilizer Applied To A Lateritic Sandy Soil In Western Australia, R. G. Mclaren, G. S.P. Ritchie Jan 1993

The Long-Term Fate Of Copper Fertilizer Applied To A Lateritic Sandy Soil In Western Australia, R. G. Mclaren, G. S.P. Ritchie

Food Science and Nutrition

A soil copper fractionation was carried out on soils sampled from plots in a long-term copper fertilizer trial on a lateritic sandy soil in Western Australia. At copper application rates up to 8.25 kg copper sulphate ha-1, a high proportion of the applied copper was initially associated with the soil organic matter. During the course of the trial (20 years), a substantial proportion of this copper became redistributed to a residual soil fraction, i.e. the residue remaining after extractions to remove organic matter and iron oxides. However, significant redistribution of copper with time was not detected in plots …


Effect Of Lupins And Pasture On Soil Acidification And Fertility In Western Australia, S. P. Loss, G. S.P. Ritchie, A. D. Robson Jan 1993

Effect Of Lupins And Pasture On Soil Acidification And Fertility In Western Australia, S. P. Loss, G. S.P. Ritchie, A. D. Robson

Food Science and Nutrition

An 'across the fence' comparison of farmer paddocks with nearby virgin bush sites was made at 3 locations, to measure the effects of lupins and subterranean clover based pastures on the chemical properties of the soil. Estimated rates of acidification in the 0-60 cm depth were 0.29-0.55 kmol H+/ha.year for wheat-lupin paddocks and 0.16-0.2 1 kmol H+/ha .year for pasture paddocks. A significant proportion of this acidification occurred below 20 cm, particularly in the lupin paddocks (up to 70% of the total). Severe water repellency had developed at 1 location that had produced 30 lupin crops with the occasional wheat …


The Effect Of Citrate And Ph On Zinc Uptake By Wheat, P. Chairidchai, G. S. P. Ritchie Jan 1993

The Effect Of Citrate And Ph On Zinc Uptake By Wheat, P. Chairidchai, G. S. P. Ritchie

Food Science and Nutrition

Zinc uptake by plants may be influenced by its reaction with organic ligands in the rhizosphere. Therefore, four experiments were conducted to examine the effects of an organic ligand (citrate) and pH on the uptake of Zn by wheat (Triticum aestivum L. emend. Thell). Plants were grown for 21 to 28 d in a nutrient solution (containing 0-0.05 µmol L-1 Zn) in a temperature controlled tank, either in the absence or presence of citrate and at constant or variable pH (3.7-7.1). Dry matter weights of plant parts and Zn content in the shoots were determined. The activities of Zn …


Effect Of Gypsum And Lime On Wheat Growth In Pots Containing An Acidic Subsoil, C. D.A. Mclay, G. S. P. Ritchie Jan 1993

Effect Of Gypsum And Lime On Wheat Growth In Pots Containing An Acidic Subsoil, C. D.A. Mclay, G. S. P. Ritchie

Food Science and Nutrition

A pot experiment was conducted to establish whether gypsum or lime could increase wheat growth in an acid subsoil. Wheat (Triticum aestivum c. v. Gutha) was grown in 3 kg of soil which had been mixed with basal nutrients and different rates of gypsum and lime. Wheat in the treatment which received no gypsum or lime showed the most severe nutrient deficiency symptoms and had the lowest shoot and root dry weights. Lime treatments increased shoot and root growth 2 to 3 fold and decreased the concentration of total Al and the calculated activities of all Al species. Gypsum increased …


Phosphorus Sorption By Gravels In Lateritic Soils, D. M. Weaver, G. S.P. Ritchie, R. J. Gilkes Jan 1992

Phosphorus Sorption By Gravels In Lateritic Soils, D. M. Weaver, G. S.P. Ritchie, R. J. Gilkes

Food Science and Nutrition

The effect of sesquioxidic gravels (>2 mm size fraction) on phosphorus sorption by two gravelly lateritic soils was investigated by phosphorus sorption experiments, X-ray diffraction, autoradiography and electron microscopy.In one soil the abundance and size of gravels decreased downslope. As the gravel content of both soils increased (13-61%), the proportion of large (>8 mm) gravels increased (0-70%). Phosphorus sorption increased in the order: (>2 mm fraction) < (whole soils) < (2 mm) decreased with increasing gravel size and increased with increasing time. Phosphorus sorption by whole soils decreased with increasing gravel content. Phosphorus sorption by the >2 mm fraction was principally by the external surfaces of the gravels. The estimation of phosphorus application rates for lateritic soils depended on the amount of phosphorus required by the plant …


Soil Tests For Aluminum Toxicity In The Presence Of Organic Matter: Laboratory Development And Assessment, M. G. Whitten, G. S.P. Ritchie Feb 1991

Soil Tests For Aluminum Toxicity In The Presence Of Organic Matter: Laboratory Development And Assessment, M. G. Whitten, G. S.P. Ritchie

Food Science and Nutrition

Al toxicity in plants is related to the activity of Al3+ and Al-hydroxy monomers in the soil solution, whereas Al complexed with ligands such as fluoride (F), sulphate (SO42-), and oxalate is not toxic. Estimation of toxic Al relies on measurement of “labile”; Al after short contact times with colorimetric reagents or cation-exchange resins. However, shifts in equilibrium may result in non-toxic forms of Al reacting with the complexing agent or resin.

A series of laboratory experiments tested the degree to which labile Al is related to Al3+ in simplified media and compared methods of …


A Soil Test For Aluminium Toxicity In Acidic Subsoils Of Yellow Earths In Western Australia, S. J. Carr, G. S.P. Ritchie, W. M. Porter Jan 1991

A Soil Test For Aluminium Toxicity In Acidic Subsoils Of Yellow Earths In Western Australia, S. J. Carr, G. S.P. Ritchie, W. M. Porter

Food Science and Nutrition

Many of the yellow earths in the Western Australian wheatbelt have naturally acidic subsoils which can reduce the yield of wheat grown on them. Current methods of assessing soil acidity cannot identify which soils have subsoil acidity severe enough to restrict wheat yields.

We conducted 53 field experiments at 34 sites in 5 regions over 3 years to determine the relationship between yield of wheat and several different indices for identifying subsoils with toxic concentrations of aluminium, Al. Initially, we identified that the concentration of aluminium, [Al], in the soil solution and in 1 : 5 0.005 M KCl extracts …


Calcium Chloride Extractable Cadmium As An Estimate Of Cadmium Uptake By Subterranean Clover, M. G. Whitten, G. S.P. Ritchie Jan 1991

Calcium Chloride Extractable Cadmium As An Estimate Of Cadmium Uptake By Subterranean Clover, M. G. Whitten, G. S.P. Ritchie

Food Science and Nutrition

Cadmium (Cd) may accumulate in soils which have been regularly fertilized with phosphate fertilizers which contain Cd originating in rock phosphate. Soil was taken from three sites in the wheatbelt of Western Australia which were estimated to have received different amounts of phosphate fertilizer over the past decade. The pH was adjusted with dilute HCl or CaCO3. No Cd was added experimentally. The concentration of Cd in the whole tops of Trifolium subterraneum cv Mt Barker grown in a glasshouse pot experiment increased from 0.2-0.8 µg g-1 dry wt at pH 6.6-6.9 (1:5 0.01 M CaCl …


A Comparison Of Soil Tests To Predict The Growth And Nodulation Of Subterranean Clover In Aluminium-Toxic Topsoils, M. G. Whitten, G. S.P. Ritchie Jan 1991

A Comparison Of Soil Tests To Predict The Growth And Nodulation Of Subterranean Clover In Aluminium-Toxic Topsoils, M. G. Whitten, G. S.P. Ritchie

Food Science and Nutrition

Total Al concentration or pH in 1∶5 10 mM CaCl2 extracts and exchangeable Al in 100 mM BaCl2 extracts cannot always distinguish between Al-toxic and Al-nontoxic topsoils. Our objectives were to compare the abilities of different measures of Al and pH in various extracts to predict the effects of acidity on growth and nodulation of subterranean clover. In a glasshouse experiment, Trifolium subterraneum L. cv. Mt Barker was grown in acidic soils from 3 sites in the Western Australian wheatbelt with different histories of phosphate fertilizer application. The pH was adjusted to give a range of …


Prediction Of Zinc Deficiency In Navy Beans (Phaseolus Vulgaris) By Soil And Plant Analyses, J. D. Armour, A. D. Robson, G. S.P. Ritchie Jan 1990

Prediction Of Zinc Deficiency In Navy Beans (Phaseolus Vulgaris) By Soil And Plant Analyses, J. D. Armour, A. D. Robson, G. S.P. Ritchie

Food Science and Nutrition

Navy beans (Phaseolus vulgaris cv. Gallaroy) were grown with 7 rates of zinc (Zn) in a Zn-deficient gravelly sandy loam in a glasshouse experiment. The plant shoots were harvested 31 days after sowing and the Zn concentration in each of 4 plant parts (YL, young leaf; YOL, young open leaf; YFEL, youngest fully expanded leaf; and whole shoots) was related to the fresh weight of the shoots. The critical Zn concentrations (mgtkg) in the plant parts determined by the 2 intersecting straight lines model were 21.1 for YL (r2 = 0.66), 17.1 for YOL (r2 = 0.83), …


Extractable Zinc In Particle Size Fractions Of Soils From Western Australia And Queensland, J. D. Armour, G. S.P. Ritchie, A. D. Robson Jan 1990

Extractable Zinc In Particle Size Fractions Of Soils From Western Australia And Queensland, J. D. Armour, G. S.P. Ritchie, A. D. Robson

Food Science and Nutrition

The zinc (Zn) content of particle size fractions of 12 mainly Zn deficient soils was measured by extraction with three contrasting extractants. The soils, which ranged from sands to a black earth, were from Western Australia and Queensland and particle size fractions (clay, silt, fine sand, coarse sand) were obtained by sieving and sedimentation after ultrasonification of soil suspended in deionized water. The extractants were concentrated HNO3/H2SO4/HClO4 (acid extractable or AE-Zn), DTPA and 0.002 M CaCl2. For each extractant, Zn contents of the fractions and whole soils were correlated with organic …


Zinc Adsorption By A Lateritic Soil In The Presence Of Organic Ligands, P. Chairidchai, G. S. P. Ritchie Jan 1990

Zinc Adsorption By A Lateritic Soil In The Presence Of Organic Ligands, P. Chairidchai, G. S. P. Ritchie

Food Science and Nutrition

Zinc adsorption by a lateritic podzolic soil was measured in the presence of 0 to 3 mmol/litre of acetate, oxalate, citrate, tricarballylate, salicylate, or catechol, or 0 to 3 mmolc/litre of humate. Zinc remaining in solution was measured by atomic absorption spectrometry after shaking the soil for 17 h at a soil/liquid ratio of 1:5 in a 0.003 mol/litre KCl solution containing 0 to 500 μmol/litre Zn and the ligands. In the absence of organic ligands, more than 95% of the zinc was adsorbed. The amount of adsorption was linearly correlated with pH and the concentration of ZnOH …


Changes With Time In The Availability Of Soil Applied Zinc To Navy Beans And In The Chemical Extraction Of Zinc From Soils, J. D. Armour, G. S.P. Ritchie, A. D. Robson Jan 1989

Changes With Time In The Availability Of Soil Applied Zinc To Navy Beans And In The Chemical Extraction Of Zinc From Soils, J. D. Armour, G. S.P. Ritchie, A. D. Robson

Food Science and Nutrition

The effect of the incubation of zinc (Zn) applied to the soil on Zn uptake and the Zn concentrations in chemical extractants was studied. In a glasshouse experiment using a Zn-deficient gravelly sandy loam, the effect of recently applied Zn was compared with that of Zn incubated with the soil for 15 days at 40°C on growth and Zn uptake by navy beans (Phaseolus vulgaris cv. Gallaroy). At the second harvest (33 days after sowing), the dry weight of shoots of recently applied Zn was consistently higher than that of incubated Zn, except at the highest rate of 1 …


The Estimation Of Free Aluminium And The Competition Between Fluoride And Humate Anions For Aluminium, G. S.P. Ritchie, M. P. Nelson, M. G. Whitten May 1988

The Estimation Of Free Aluminium And The Competition Between Fluoride And Humate Anions For Aluminium, G. S.P. Ritchie, M. P. Nelson, M. G. Whitten

Food Science and Nutrition

Three equations for estimating the concentration of free aluminium, [Al3+], from the activity of free fluoride, (F-), were compared to assess their suitability for estimating [Al3+] in acid soil solutions and in competition studies. We then studied the ability of humic acids to compete with F for Al by comparing the behaviour of the humic acids in the presence of F and Al with that of several carboxylic acids under the same conditions. All three methods of estimating [Al ] were limited in their applicability to acid soil solutions but were uitable for estimating …


A Preliminary Evaluation Of Resin Extractable Molybdenum As A Soil Test, G. S.P. Ritchie Apr 1988

A Preliminary Evaluation Of Resin Extractable Molybdenum As A Soil Test, G. S.P. Ritchie

Food Science and Nutrition

Resin extractable Mo explained 72% of the variation in yield of wheat (Triticum aestivum) grown on ten acid soils as measured by the relative yield of the tops or by the uptake of Mo by the youngest emerged blade.


Phosphorus Leaching In Sandy Soils. I. Short-Term Effects Of Fertilizer Applications And Environmental Conditions, D. M. Weaver, G. S.P. Ritchie, G. C. Anderson, D. M. Deeley Jan 1988

Phosphorus Leaching In Sandy Soils. I. Short-Term Effects Of Fertilizer Applications And Environmental Conditions, D. M. Weaver, G. S.P. Ritchie, G. C. Anderson, D. M. Deeley

Food Science and Nutrition

The consequences of previous as well as current environmental conditions and management practices on the potential for phosphorus (P) to be lost by drainage from sandy soils in the short term (< 1 year) were studied in the laboratory and the field. The potential for P losses by drainage was estimated by measuring soil solution P levels and rapidly released P. Rapidly released P was measured by determining the concentration of dissolved inorganic P contained in filtered (µm) soil solutions after incubating soil at saturation for 15 min at ambient temperature. In the laboratory, sandy soils were incubated with ordinary superphosphate, coastal superphosphate (a granulated mixture of equal parts of superphospate, rock phosphate and elemental sulfur) or lime-superphosphate (a lime-reverted superphosphate with 18% kiln dust) and sequentially desorbed with deionized water. The effects of the extent of leaching, fertilizer type, application rate and the time of contact with the soil on soil solution P levels were investigated. The influence of annual pasture death and summer rainfall on rapidly released P in soils that had been pre-treated by leaching were also investigated.

Phosphorus concentrations decreased logarithmically in the successive supernatants of the sequentially desorbed soils. More P was desorbed from soils incubated with superphosphate and lime-superphosphate than soil incubated with coastal superphosphate. At each level of pre-leaching, the P concentrations in the soil solution increased with increasing time. The level, to which the P concentration in the soil solution increased at each time, decreased with increased extent of pre-leaching. The …


Phosphorus Leaching In Sandy Soils. Ii. Laboratory Studies Of The Long-Term Effects Of The Phosphorus Source, D. M. Weaver, G. S.P. Ritchie, G. C. Anderson Jan 1988

Phosphorus Leaching In Sandy Soils. Ii. Laboratory Studies Of The Long-Term Effects Of The Phosphorus Source, D. M. Weaver, G. S.P. Ritchie, G. C. Anderson

Food Science and Nutrition

Long-term phosphorus (P) losses and gains in sandy soils continuously fertilized with either ordinary superphosphate or coastal superphosphate (a granulated mixture of superphosphate, rock phosphate and elemental sulfur) or previously fertilized with superphosphate were investigated under leaching conditions in columns in the laboratory. The soils were subjected to 10 consecutive cycles designed to simulate the mediterranean weather conditions in the Harvey region of the Coastal Plain of Western Australia. Each cycle consisted of a wet phase during which the equivalent of 850 mm of rainfall was leached through the soil and a drier phase during which the soil was incubated …


The Effectiveness Of Lime-Based Amendments And Bauxite Residues At Removing Phosphorus From Piggery Effluent, D. M. Weaver, G. S. P. Ritchie Jan 1987

The Effectiveness Of Lime-Based Amendments And Bauxite Residues At Removing Phosphorus From Piggery Effluent, D. M. Weaver, G. S. P. Ritchie

Food Science and Nutrition

Piggery effluent may contribute to the eutrophication of waterways, if it is not treated before disposal, because of high levels of phosphorus. Limes and red muds (a residue from bauxite refining) were used to remove phosphorus from piggery effluent (41 mg litre-1 total P). Lime-based amendments were more effective than the red muds at removing phosphorus when compared at the same liquid: solid ratios. Based on laboratory data, the cost of treating effluent increased rapidly as the final required phosphorus concentration decreased to less than 4 mg litre-1. Kiln dust was the cheapest amendment tested down to …


Relative Toxicities Of Inorganic Aluminum Complexes To Barley, R. S. Cameron, G. S.P. Ritchie, A. D. Robson Jan 1986

Relative Toxicities Of Inorganic Aluminum Complexes To Barley, R. S. Cameron, G. S.P. Ritchie, A. D. Robson

Food Science and Nutrition

The inorganic forms of Al in the soil solution that decrease plant growth in acid soils have not been clearly identified. Therefore, we examined the effects of Al and its complexes with F- and SO42- on the root elongation of barley (Hordeum vulgare) in nutrient solutions containing 3333 μmol Ca L-1 and 6 μmol B L-1 at pH 4.5. The anions were chosen because of their presence in the soil solution at levels sufficient to complex Al. The toxicity of 0 to 100 μmol Al L-1 was studied in the presence of …


Estimates Of Soil Solution Ionic Strength And The Determination Of Ph In West Australian Soils, P. J. Dolling, G. S.P. Ritchie Jan 1985

Estimates Of Soil Solution Ionic Strength And The Determination Of Ph In West Australian Soils, P. J. Dolling, G. S.P. Ritchie

Food Science and Nutrition

The average ionic strength of 20 West Australian soils was found to be 0.0048. The effects of three electrolytes (deionized water, CaCl2 and KNO3), three ionic strengths (0.03, 0.005 and soil ionic strength at field capacity, Is) and two soil liquid ratios (1:5 and 1:10) on the pH of 15 soils were investigated. pH measurements in solutions of ionic strength 0.005 differed the least from measurements made at Is. The differences that occurred in comparisons with distilled water or CaCl2 of ionic strength 0.03 (0.01 M) were much greater (≥0.4 pH …


The Role Of Organic Matter In Soil Acidification, G. S.P. Ritchie, P. J. Dolling Jan 1985

The Role Of Organic Matter In Soil Acidification, G. S.P. Ritchie, P. J. Dolling

Food Science and Nutrition

The pH and buffer capacity of two soils increased or remained constant after incubation with different amounts of plant material (lucerne cham at field capacity and when air dry. For both soils, the pH changes were greater at field capacity, whereas the buffer capacities were independent of the water treatments. The pH changes observed could be explained in terms of the organic anion concentration of the plant material. The results indicate that the initial soil pH and the anion concentration (i.e. the per cent dissociation of soluble organic acids when released into the soil) determine the acidifying effect of organic …


The Pzc Of Mercury In The Presence Of Humic Acids And Their Complexes With Aluminium, Geraldine S.P. Ritchie, Alan M. Posner, Ian M. Ritchie Jun 1981

The Pzc Of Mercury In The Presence Of Humic Acids And Their Complexes With Aluminium, Geraldine S.P. Ritchie, Alan M. Posner, Ian M. Ritchie

Food Science and Nutrition

Variation of the lifetime of a mercury drop with potential was used to determine the pzc of mercury in the presence of soil humic acids and their aluminium complexes. In all cases there was an overall net shift in the pzc in the cathodic direction. Variation in the extent of the shift with pH and concentration indicated greater adsorption of negatively charged species. The shift was smaller in the presence of aluminium humates, probably due to a decrease in the negative charge of the humic acid molecules after complexing. The use of electroanalytical techniques for metal speciation studies in soils …


The Determination Of Trace Levels Of Aluminum By Differential Pulse Polarography, Geraldine S. P. Ritchie, Alan M. Posner, Ian M. Ritchie Jan 1980

The Determination Of Trace Levels Of Aluminum By Differential Pulse Polarography, Geraldine S. P. Ritchie, Alan M. Posner, Ian M. Ritchie

Food Science and Nutrition

The direct determination of aluminium in aqueous solutions by differential pulse polarography is described. If the pH is carefully controlled to 4.00 ± 0.01, there is a linear relationship between the peak height of the polarographic wave and the aluminium concentration up to 2.5 × 10-5 mol dm-3. The coefficient of variation is about 4% at the 10-5 mol dm-3 level. With increasing aluminium concentrations, the relationship ceases to be linear, and above 9 × 10-5 mol dm-3, the peak splits, probably because of hydrolysis and polymerisation. Na+, NH4 …