Monomeric Aluminum Concentrations Research Articles

Response of Water Chemistry and Young-of-Year Brook Trout to Channel and Watershed Liming in Streams Showing Lagging Recovery from Acidic Deposition

Reductions in sulfur emissions have initiated chemical recovery of surface waters impacted by acidic deposition in the Adirondack region of New York State. However, acidified streams remain common in the region, which limits recovery of brook trout (Salvelinus fontinalis) populations. To investigate liming as a method to accelerate recovery of brook trout, the channels of two acidified streams were limed annually from 2012 to 2015, and an entire watershed of a third acidified tributary was limed by helicopter in 2013. Stream flow, water chemistry, and density of young-of-year (YOY) brook trout were measured in limed streams, an untreated acidified stream, and a buffered reference stream. Lime additions increased pH and acid-neutralizing capacity and decreased inorganic monomeric aluminum concentrations to less than 2.0 μmol/L, the minimum concentration at which in situ brook trout mortality has been documented. However, of the two channel-limed streams, only stream T8 showed a significant response (P < 0.01) in YOY density, increasing from a mean of 0.4 fish/m2 before liming to 2.7 fish/m2 after liming. No YOY brook trout response was observed in the stream within the limed watershed. Groundwater inputs to streams were identified by relative differences in temperature and concentrations of silica and sodium. YOY brook trout densities increased only in the channel-limed stream (T8) with suitable groundwater inputs for fall spawning and a summer nursery. Results suggest that targeted liming of acidified streams with the necessary groundwater habitat could be beneficial in accelerating recovery of brook trout populations.

Use of soil-streamwater relationships to assess regional patterns of acidic deposition effects in the northeastern USA

Declines of acidic deposition levels by as much as 50% since 1990 have led to partial recovery of surface waters in the northeastern USA but continued depletion of soil calcium through this same period suggests a disconnection between soil and surface water chemistry. To investigate the role of soil-surface water interactions in recovery from acidification, the first regional survey to directly relate soil chemistry to stream chemistry during high flow was implemented in a 4144-km2 area of the Catskill region of New York, where acidic deposition levels are among the highest in the East. More than 40% of 95 streams sampled in the southern Catskill Mountains were determined to be acidified and had inorganic monomeric aluminum concentrations that exceeded a threshold that is toxic to aquatic biota. More than 80% likely exceeded this threshold during the highest flows, but less than 10% of more than 100 streams sampled were acidified in the northwestern portion of the region. Median Oa horizon soil base saturation ranged from 50% to 80% at 200 sites across the region, but median base saturation in the upper 10 cm of the B horizon was less than 20% across the region and was only 2% in the southern area. Aluminum is likely to be interfering with root uptake of calcium in the mineral horizon in approximately half the sampled watersheds. Stream chemistry was highly variable over the Catskill region and, therefore, did not always reflect the calcium depletion of the B horizon that our sampling suggested was nearly ubiquitous throughout the region. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Influence of composite flocculant of PAC and MBFGA1 on residual aluminum species distribution

In general, majority of biomaterials have shown good biosorption capacities towards certain of metal ions. In this work, microbial flocculant GA1 (MBFGA1) compound with PAC was used to control the residual aluminum in flocculation water treatment. The fluorescence spectrophotometry combined with different pretreatment methods was employed to divide the species of aluminum and determine their concentration. The results indicated that non-labile monomeric aluminum was the dominant specie in residual aluminum and addition of MBFGA1 could efficiently eliminate them. Two quadratic polynomial models with the response variables of flocculating rate and labile monomeric aluminum concentration were established by response surface methodology, respectively. The optimal flocculating conditions were MBFGA1 at 109.37mg/L, PAC at 81.87mg/L, initial pH at 8.5, time duration of stir 72.5min and ambient temperature at 24.3°C. Fourier transform-infrared spectra and environmental scanning electron microscope analysis indicated that MBFGA1 holded a large number of functional groups, which had strong capacity on binding aluminum and reducing its residual level during coagulation–flocculation.

Bacterial Community Structure of Acid-Impacted Lakes: What Controls Diversity?

Although it is recognized that acidification of freshwater systems results in decreased overall species richness of plants and animals, little is known about the response of aquatic microbial communities to acidification. In this study we examined bacterioplankton community diversity and structure in 18 lakes located in the Adirondack Park (in the state of New York in the United States) that were affected to various degrees by acidic deposition and assessed correlations with 31 physical and chemical parameters. The pH of these lakes ranged from 4.9 to 7.8. These studies were conducted as a component of the Adirondack Effects Assessment Program supported by the U.S. Environmental Protection Agency. Thirty-one independent 16S rRNA gene libraries consisting of 2,135 clones were constructed from epilimnion and hypolimnion water samples. Bacterioplankton community composition was determined by sequencing and amplified ribosomal DNA restriction analysis of the clone libraries. Nineteen bacterial classes representing 95 subclasses were observed, but clone libraries were dominated by representatives of the Actinobacteria and Betaproteobacteria classes. Although the diversity and richness of bacterioplankton communities were positively correlated with pH, the overall community composition assessed by principal component analysis was not. The strongest correlations were observed between bacterioplankton communities and lake depth, hydraulic retention time, dissolved inorganic carbon, and nonlabile monomeric aluminum concentrations. While there was not an overall correlation between bacterioplankton community structure and pH, several bacterial classes, including the Alphaproteobacteria, were directly correlated with acidity. These results indicate that unlike more identifiable correlations between acidity and species richness for higher trophic levels, controls on bacterioplankton community structure are likely more complex, involving both direct and indirect processes.

Effect of Navy Chaff Release on Aluminum Levels in an Area of the Chesapeake Bay

The U.S. Navy uses aluminized glass chaff as a passive countermeasure for radar-guided threats to aircraft and surface ships. Over the last 25 years, several hundred thousand pounds of aluminized chaff have been released during flight operations over a training area on the Chesapeake Bay. There is concern that these releases have resulted in the accumulation of significant amounts of aluminum in the soil and sediment of this training area. This study compares the exchangeable and monomeric aluminum content of sediment within the affected area with that of samples taken from outside the training area. We found a less than twofold increase in the content of organic monomeric aluminum in samples taken from the affected area versus background samples, whereas inorganic monomeric aluminum concentrations within the affected area were significantly lower than background. These results suggest that chaff releases have not resulted in a significant accumulation of aluminum in this training area.

Chemical and Fishery Responses to Mitigative Liming of an Acidic Stream, Dogway Fork, West Virginia

AbstractLimestone neutralization of the acidic water of Dog‐way Fork in West Virginia resulted in significant improvements in both water quality and fish populations. Pretreatment water chemistry showed the stream to be highly acidified by acid precipitation, with pH under 5.0 and high aluminum concentrations. During treatment, the goals for the target area of pH 6.5 and acid‐neutralizing capacity of 50 μmeq/L were met for 75.8% and 67% of the time, respectively. A pH 6.0 or above was maintained over 93% of the time. Monomeric aluminum concentrations were reduced significantly, and calcium to hydrogen ionic ratios were over 10 in the target area. Prior to treatment, no resident fish population was found in Dogway Fork. During five years of treatment, conditions were favorable for fish reproduction and survival. Eight fish species inhabited the stream, six were reproducing there, and a fishable brook trout population was established.

The influence of some parameters upon the aluminium leaching out by limousin soils through batch reactor

In order to evaluate the influence of an intensive forestry on the monomeric aluminium and organic matter release by the Limousin forest (France), an acidic brown earth soil planted with 3 different forests (centenary Douglas, young Douglas and Chesnuts) was selected. According to batch reactor experiments, the results show that all A horizons the most contaminated distilled water with monomeric aluminium and organic matter. The higher released concentrations of monomeric aluminium were obtained with the old Douglas upper soil horizon. When the soil was in contact with acidic solution, the more the pH was acidic, the more monomeric aluminium released concentration was important.

Acidification of an estuarine tributary in eastern Australia due to drainage of acid sulfate soils

Episodic acidification (pH &lt;5) of estuarine tributaries caused by the oxidation of sulfidic floodplain sediments is widespread in eastern Australia. Drainage and flood mitigation works promote oxidation and the export of sulfuric acid and dissolved aluminium and iron into streams. This paper examines the acidification of a tidal reach on the Richmond River, New South Wales. Acid discharge is controlled by the floodplain water balance, drainage of shallow acid groundwater, and tidal floodgate operation. Floodgates store acid waters for more than six months. Acid discharges ranged from short pulses during light rains to ~950 t of sulfuric acid in a major flood that acidified the reach for over seven weeks. Extensive iron flocs accompanied acidification and coated the benthos. The chemistry of the reach reflected mixing of acid groundwater with upland waters and showed pH-dependent enhancement or depletion of species relative to chloride. Concentrations of monomeric aluminium were over 300 times larger than local (ANZECC) guidelines and 90 km of the river were acidified after floods. The estimated rate of sulfuric acid production from the floodplain is ~300 kg ha-1 year-1 and discharge may occur for over 1000 years. Management options are considered; however, the long-term consequences of acidification of tidal reaches are unknown.

The influence of some parameters upon the aluminium leaching out by limousin soils through batch reactor

In order to evaluate the influence of an intensive forestry on the monomeric aluminium and organic matter release by the Limousin forest (France), an acidic brown earth soil planted with 3 different forests (centenary Douglas, young Douglas and Chesnuts) was selected. According to batch reactor experiments, the results show that all A horizons the most contaminated distilled water with monomeric aluminium and organic matter. The higher released concentrations of monomeric aluminium were obtained with the old Douglas upper soil horizon. When the soil was in contact with acidic solution, the more the pH was acidic, the more monomeric aluminium released concentration was important.

Relationships between afforestation, water chemistry and fish stocks in an upland catchment in south west Scotland

The soils and waters in the Galloway hills of south-west Scotland have undergone considerable acidification during the present century. The aims of this study were to examine the extent to which afforestation can influence water chemistry, and the occurrence of fish stocks within an individual catchment in this area. Studies were carried out at 45 sites in the Bladnoch catchment during 1994. River water samples were collected at all sites and determinations made of pH, total organic carbon, calcium and monomeric aluminium concentrations. In order to quantify the size and abundance of fish populations, electrofishing was carried out at 21 of the sites. Estimates of afforestation were made by a combination of field surveys and the use of 1∶:10 000 scale ordnance survey maps. The presence of coniferous trees had a substantial affect on water chemistry. In areas where the whole catchment was afforested, the water pH was 0.7 units lower than in unafforested areas (p<0.001). Afforestation was also correlated with low concentrations of calcium, and increases in the concentrations of monomeric aluminium and total organic carbon. There was a clear relationship between fish populations and water chemistry. Numbers of trout were positively correlated with pH (r2=0.69; p<0.001), and with concentrations of calcium (r2=0.55; p<0.001). The study has shown that salmonid fish populations are sensitive to acidity and the associated changes in river water chemistry; these problems were exacerbated by afforestation.

The Effects of Low pH and Aluminum on Breeding Success in the Frog Rana temporaria

The effects of low pH on fertilization and embryonic development in Rana temporaria (L.) were studied in the laboratory and field. In the field, fertilization success was reduced principally by high concentrations of inorganic monomeric aluminum, while embryonic mortality was caused mainly by low water temperatures. Most dead eggs were at the mid to late cleavage or early gastrula stage. In the laboratory, embryonic survival decreased with increasing inorganic monomeric aluminum concentration at pH 4.5. High concentrations of inorganic monomeric aluminum also increased the number of embryos which died in the early stages of development, and increased the proportion of embryos which remained constricted within the perivitelline membrane and failed to hatch

Soil and soil water studies at the HUMEX site

Changes to natural organic compounds by acid deposition and subsequent effects on Al mobilization are not well understood. The HUMEX catchment-scale acidification experiment in western Norway offers a unique possibility for an integrated assessment of these interactions. In this report, the soil and soil water chemical data from the HUMEX site, from before and after the onset of experimental acidification, are used to characterize the catchment. Changes in soil water chemistry are discussed and controls on dissolved organic carbon are addressed in relation to Al mobilization. Decreases in the concentration of dissolved organic carbon (DOC) and organic Al fractions were found in soil water after the treatment started. These changes were related to an increase in soil water sulphate concentrations. The sulphate levels showed a significant increase (on a 95% level) in four of ten soil horizons while nitrate remained nearly unchanged. In organic soils, where the dissolved organic carbon content was high, the major control for monomeric aluminum concentration appeared to be the amount of exchangeable aluminum in the soil. In mineral soils, the gibbsite dissolution may govern inorganic Al concentrations in soil water, though substantial undersaturation was found when DOC was high.

Preliminary analysis of water and solute movement beneath a coniferous hillslope in Mid-Wales, U.K.

Streams draining coniferous forests are often loaded with solutes such as hydrogen ion, sulphate, nitrate and aluminium. As a result, fish populations can be reduced and water quality may fall below recommended potable standards. The transport of ions into water-courses is governed by the movement of water. Within most temperate and tropical areas the stream discharge and chemistry, during periods of rapid runoff, is dominated by the exfiltration of water and solutes from stream-side soils. The movement of water to stream-side or ‘riparian’ areas remains, however, an enigma. This paper attempts to explain how the riparian area might be rapidly recharged during storm events. Two analytical techniques, the free-surface method and tangent-continuity method, are applied to hydrological properties monitored on a steep coniferous hillslope, during a selected storm event. Comparison of the ionic concentrations of waters within each component of the hydrological system, is used to verify the hydrological analysis. Perched water-tables developed within the basal zones of the O/Ah and Eag soil horizons of the steep podzolic hillslope, during all major storm events. Most of the rapid response within the riparian zone could be explained by lateral flow in these near-surface soil horizons, particularly in the saturated basal zones. This pathway is corroborated by the similarity of riparian zone and near-surface (or topsoil) chemistries. Relatively low concentrations of monomeric aluminium and relatively high concentrations of chloride, sodium and hydrogen ion were observed within these zones, compared with the subsoil (Bsl and B/C) horizons.

Inorganic Monomeric Aluminum and pH as Predictors of Acidic Water Toxicity to Brook Trout (Salvelinus fontinalis)

Inorganic monomeric aluminum concentrations were found to be the primary determinant of survival of brook trout feeding fry exposed for 21 d to various combinations of total aluminum and pH, plus several concentrations of fluoride or DOC, or several temperatures. Total aluminum concentrations in the 4 × 4 × 4 experimental matrices ranged from 3–1276 ppb, pH from 4.4–6.7, fluoride from &lt;10–328 ppb, DOC from &lt;1–9.2 ppm, and temperatures from 5.4–12.0 °C. Stepwise logistic regression was used to determine the significance of the effect of each water quality variable on survival. Inorganic monomeric aluminum accounted for 78–98% of the variation in survival. Except in the fluoride bioassay where pH was not significant, pH was the second-most important variable, accounting for up to 16% of the variation in survival. Fluoride or temperature accounted for 1–2% of the variation in survival, while DOC accounted for 6% of the variation in survival.

Aluminum and Acid Toxicity to Two Strains of Brook Trout (Salvelinus fontinalis)

Two strains of 1 yr-old brook trout were exposed to 14 combinations of pH, aluminum, and calcium during a 28-d experiment. Survival, weight, and gill histology of both strains were affected similarly by pH, aluminum, and calcium exposure. Survival was reduced at inorganic monomeric aluminum concentrations (IA1) of 29 μg/L at pH 5.2 and [Formula: see text] at pH 4.4 and 4.8. Fish weight was reduced with exposure to pH below 4.8 or aluminum concentrations [Formula: see text]. The gills sampled from fish exposed to low pH exhibited lifting of the outer epithelium and hypertrophy (increase in size) of chloride and epithelial cells. The response of gills sampled from fish exposed to low pH and elevated aluminum was more pronounced relative to the low pH exposure alone. In addition to the effects observed in the low pH exposed fish, the gills from fish exposed to both acid and aluminum exhibited vacuolation and degeneration of epithelial and chloride cells and the presence of dense cells. Finally, fish confined in PVC tubes designed to mimic in situ field exposure procedures were more sensitive to the toxic effects of acid and aluminum compared to free-swimming fish. Caution must be taken when extrapolating safe field levels from in situ exposures of caged fish.

Apparent Monomeric Aluminum Concentrations in the Presence of Humic and Fulvic Acid and Other Ligands: An Intermethod Comparison Study

Abstract The effects of humic and fulvic acids and other ligands on apparent monomeric Al concentration were determined by three analytical methods: 8-hydroxyquinoline/MIBK, pyrocatechol violet, and fluoride complexation kinetics. Citric acid and CDTA were found to cause the greatest reduction. Also, ligands with phenolic and/or carboxylic groups in the ortho position caused significant reduction in apparent total monomeric Al concentrations. Each ligand affected each analytical method in varying degrees. The extent to which each method was affected was dependent upon not only the configuration of the competing ligand, but also the relative stability of the Al/measurement-ligand complex, the pH at which the analytical method operated, and the kinetics of the measurement reaction. These factors must be taken into consideration when interpreting total monomeric Al values generated by different analytical methods, particularly when a large fraction of the monomeric Al pool is comprised of organically-bound f...

The mobilization of aluminum in a natural soil system: Effects of hydrologic pathways

A two‐component soil water flow model was used in conjunction with an equilibrium speciation model WATEQF to study aluminum mobility in soils of a forested watershed, White Oak Run, in the Shenandoah National Park, Virginia. Soil solution samples, taken from the O, E, B, C1, and C2 horizons, were collected from zero‐tension lysimeters designed to collect faster gravitational macropore flow and tension lysimeters designed to collect slower capillary micropore flow. Dissolved aluminum was fractionated into acid‐soluble, inorganic monomeric, and organic monomeric aluminum. Soil water aluminum concentrations decreased with depth indicating that the deep soil is a sink for aluminum. All waters contained significant concentrations of acid‐soluble aluminum and exhibited a negative correlation between pH and the inorganic monomeric aluminum concentrations. Water in the shallow soil showed distinctly different chemical compositions for the two flow types, while C horizon micropore and macropore waters were more similar. Because of its shorter residence time, water flowing in deep soil macropores underwent less extensive neutralization and immobilization of aqueous aluminum than micropore water. The O horizon macropore waters were undersaturated for all hydroxide, silicate, and sulfate mineral phases considered. The C horizon samples from both flow types were near equilibrium with respect to kaolinite and synthetic gibbsite, indicating that mineral solubility controls water chemistry in the deep soil, while organic substances are the key control in the shallow macropore waters.