Spatial distribution and management of total actual acidity in an acid sulfate soil environment, McLeods Creek, northeastern NSW, Australia

Spatial distribution of brackishwater pond soil has important role in the system of bioenvironment including brackishwater pond environment. This research was aimed to determine the spatial distribution of some chemical characteristics of an acid sulfate soil-affected brackishwater pond in coastal area of Luwu Regency South Sulawesi Province, Indonesia. ALOS AVNIR-2 images (acquisition 16 May 2008, 16 October 2008, 17 September 2009) were integrated with Indonesian Topographic maps to obtain base map. Sampling soil points were determined by simple random sampling in 104 points for two different soil depths i.e. 0-0.2 m and 0.5-0.7 m. A total of 18 soil chemical characteristics was measured in the field and analyzed in the laboratory. Geostatistic using kriging method in the ArcGIS 9.3 software was used to interpolate the data. The results of this study indicated that in general pond soil chemical characteristics in Luwu Regency could be categorized with high variability or relatively heterogenic wi th the value of var iation coefficient more than 36%. The soil characteristics that explain acidity had shown similar pattern in spatial distribution as well as other soil characteristics with soil nutrient. The high value of pH and low value of PO4 were generally found in the northern part of Luwu Regency, including East Lamasi, East Walenrang, Bua, and Ponrang Subdistricts. It is recommended that soil management in brackishwater ponds of Luwu Regency could be based on soil chemical characteristics so its could improve the production through minimizing the input, increasing carrying capacity, and avoiding environmental degradation.

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Soil pH, oxygen availability, and the rate of sulfide oxidation in acid sulfate soil materials: implications for environmental hazard assessment

Soil Research ◽

10.1071/sr03110 ◽

2004 ◽

Vol 42 (6) ◽

pp. 509 ◽

Cited By ~ 16

Author(s):

Nicholas J. Ward ◽

Leigh A. Sullivan ◽

Richard T. Bush

Keyword(s):

Hazard Assessment ◽

Oxygen Diffusion ◽

Sulfide Oxidation ◽

Oxygen Availability ◽

Environmental Hazard ◽

Acid Sulfate Soil ◽

Acid Sulfate ◽

Plastic Bags ◽

Actual Acidity ◽

Environmental Hazard Assessment

The potential environmental hazard of acid sulfate soil (ASS) materials is directly related to both the net acidity and the rate that actual acidity is released from these soil materials into the environment. While current environmental hazard assessment techniques for ASS materials are able to quantify the net acidity, they do not take account of differences in the rate of sulfide oxidation (the dominant source of actual acidity) and differences in the rate of acidification. In this study the rate of sulfide oxidation during incubation was examined for 4 ASS materials. The effect of pH and oxygen availability on the rate of sulfide oxidation was assessed. The ASS materials were incubated in: (i) gauze where oxygen diffusion was not restricted, and (ii) sealed 100-µm-thick plastic bags which greatly limited oxygen diffusion. When oxygen diffusion was not restricted, an accelerated oxidation of sulfide occurred when the pH decreased below pH 4.0. The accelerated rate of sulfide oxidation at such low pH did not occur when oxygen diffusion was limited. This study indicates that the initial pH of an ASS material is a useful additional indicator of the potential environmental hazard of an ASS material when oxygen is expected to be non-limiting, such as when ASS materials are excavated and stockpiled. The recommended action criteria need to be reassessed, as the data indicate that the current criteria are conservative for alkaline and neutral ASS materials, but should be lowered for all acidic ASS materials (i.e. pH <5.5) to 0.03% sulfide regardless of texture.

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Iron precipitate accumulations associated with waterways in drained coastal acid sulfate landscapes of eastern Australia

Marine and Freshwater Research ◽

10.1071/mf04072 ◽

2004 ◽

Vol 55 (7) ◽

pp. 727 ◽

Cited By ~ 63

Author(s):

L. A. Sullivan ◽

R. T. Bush

Keyword(s):

Mine Drainage ◽

Chemical Properties ◽

Soil Surface ◽

Low Flow ◽

Acid Sulfate Soil ◽

Acid Sulfate ◽

Iron Mineral ◽

Eastern Australia ◽

Actual Acidity ◽

And Chemical Properties

Iron precipitate accumulations from surface environments surrounding waterways (such as the side of drains and soil surface horizons) in acid sulfate soil landscapes were analysed for their mineralogy, micromorphology and chemical properties. Schwertmannite (Fe8(OH)5.5(SO4)1.25) was the dominant mineral in these accumulations. Goethite (α-FeOOH) was the other iron precipitate mineral identified in these accumulations and the data indicate that this iron mineral was formed from schwertmannite, often as pseudomorphs after schwertmannite. The schwertmannite in these accumulations had similar morphology and chemical properties to schwertmannite reported for environments affected by acid mine drainage. The activity of Fe3+ in the drainage waters in these landscapes appears to be controlled by schwertmannite during both low flow (dry season) and flood conditions. Iron precipitate accumulations contained appreciable amounts of stored acidity (i.e. titratable actual acidity of between 164 and 443 mol (H+) t–1, and 1900 to 2580 mol (H+) t–1 of schwertmannite upon complete conversion to goethite) that tends to buffer these waters to very acidic conditions (i.e. pHs ~3.0–3.5). The relationship between water quality (i.e. pH and sulfate concentration) and type of iron precipitate mineral formed should enable the mineralogy of the iron precipitates in these surface environments to be used to help identify the degree of severity of degradation in these acid sulfate soil landscapes and to monitor the effectiveness of remediation programmes.

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Iron monosulfide formation and oxidation in drain-bottom sediments of an acid sulfate soil environment

Applied Geochemistry ◽

10.1016/j.apgeochem.2004.04.004 ◽

2004 ◽

Vol 19 (11) ◽

pp. 1837-1853 ◽

Cited By ~ 45

Author(s):

Jodie Smith ◽

Michael D. Melville

Keyword(s):

Bottom Sediments ◽

Soil Environment ◽

Acid Sulfate Soil ◽

Acid Sulfate ◽

Iron Monosulfide

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PEUBAH KUALITAS AIR YANG MEMPENGARUHI PERTUMBUHAN RUMPUT LAUT (Gracilaria verrucosa) DI TAMBAK TANAH SULFAT MASAM KECAMATAN ANGKONA KABUPATEN LUWU TIMUR PROVINSI SULAWESI SELATAN

Jurnal Riset Akuakultur ◽

10.15578/jra.4.1.2009.125-138 ◽

2009 ◽

Vol 4 (1) ◽

pp. 125

Author(s):

Akhmad Mustafa ◽

Rachmansyah Rachmansyah ◽

Dody Dharmawan Trijuno ◽

Ruslaini Ruslaini

Keyword(s):

Water Quality ◽

Growth Rate ◽

Ammonium Phosphate ◽

Gracilaria Verrucosa ◽

Acid Sulfate Soils ◽

Acid Sulfate Soil ◽

Acid Sulfate ◽

Independent Variables ◽

Water Quality Variables ◽

Sulfate Soils

Rumput laut (Gracilaria verrucosa) telah dibudidayakan di tambak tanah sulfat masam dengan kualitas dan kuantitas produksi yang relatif tinggi. Oleh karena itu, dilakukan penelitian yang bertujuan untuk mengetahui peubah kualitas air yang mempengaruhi laju pertumbuhan rumput laut di tambak tanah sulfat masam Kecamatan Angkona Kabupaten Luwu Timur Provinsi Sulawesi Selatan. Pemeliharaan rumput laut dilakukan di 30 petak tambak terpilih selama 6 minggu. Bibit rumput laut dengan bobot 100 g basah ditebar dalam hapa berukuran 1,0 m x 1,0 m x 1,2 m. Peubah tidak bebas yang diamati adalah laju pertumbuhan relatif, sedangkan peubah bebas adalah peubah kualitas air yang meliputi: intensitas cahaya, salinitas, suhu, pH, karbondioksida, nitrat, amonium, fosfat, dan besi. Analisis regresi berganda digunakan untuk menentukan peubah bebas yang dapat digunakan untuk memprediksi peubah tidak bebas. Hasil penelitian menunjukkan bahwa laju pertumbuhan relatif rumput laut di tambak tanah sulfat masam berkisar antara 1,52% dan 3,63%/hari dengan rata-rata 2,88% ± 0,56%/hari. Di antara 9 peubah kualitas air yang diamati ternyata hanya 5 peubah kualitas air yaitu: nitrat, salinitas, amonium, besi, dan fosfat yang mempengaruhi pertumbuhan rumput laut secara nyata. Untuk meningkatkan pertumbuhan rumput laut di tambak tanah sulfat masam Kecamatan Angkona Kabupaten Luwu Timur dapat dilakukan dengan pemberian pupuk yang mengandung nitrogen untuk meningkatkan kandungan amonium dan nitrat serta pemberian pupuk yang mengandung fosfor untuk meningkatkan kandungan fosfat sampai pada nilai tertentu, melakukan remediasi untuk menurunkan kandungan besi serta memelihara rumput laut pada salinitas air yang lebih tinggi, tetapi tidak melebihi 30 ppt.Seaweed (Gracilaria verrucosa) has been cultivated in acid sulfate soil-affected ponds with relatively high quality and quantity of seaweed production. A research has been conducted to study water quality variables that influence the growth of seaweed in acid sulfate soil-affected ponds of Angkona Sub-district East Luwu Regency South Sulawesi Province. Cultivation of seaweed was done for six weeks in 30 selected brackishwater ponds. Seeds of seaweed with weight of 100 g were stocked in hapa sized 1.0 m x 1.0 m x 1.2 m. Dependent variable that was observed was specific growth rate, whereas independent variables were water quality variables including light intensity, salinity, temperature, pH, carbondioxide, nitrate, ammonium, phosphate, and iron. Analyses of multiple regressions were used to determine the independent variables which could be used to predict the dependent variable. Research result indicated that relative growth rate of seaweed in acid sulfate soils-affected brackishwater ponds ranged from 1.52% to 3.63%/day with 2.88% ± 0.56%/day in average. Among nine observed water quality variables, only five variables namely: nitrate, salinity, ammonium, phosphate and iron influence significantly on the growth of seaweed in acid sulfate soils-affected brackishwater ponds. The growth of seaweed in acid sulfate soils-affected brackishwater ponds of Angkona District East Luwu Regency, can be improved by using nitrogen-based fertilizers to increase ammonium and nitrate contents and also fertilizers which contain phosphorus to improve phosphate content to a certain level. Pond remediation to decrease iron content and also rearing seaweed at higher salinity (but less than 30 ppt) can also be alternatives to increase the growth of seaweed.

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