scholarly journals Research Advances on Soil Formation of Bauxite Residues

2015 ◽  
Vol 03 (02) ◽  
pp. 13-18 ◽  
Author(s):  
生国 薛
Keyword(s):  
Soil Formation ◽  
Bauxite Residues

Indicators of soil formation in restored bauxite residues

2013 ◽  
Vol 58 ◽  
pp. 63-68 ◽  
Author(s):  
R. Courtney ◽  
T. Harrington ◽  
K.A. Byrne
Keyword(s):  
Soil Formation ◽  
Bauxite Residues

Bauxite residue neutralisation precipitate stability in acidic environments

2013 ◽  
Vol 10 (6) ◽  
pp. 455 ◽  
Author(s):  
Sara J. Couperthwaite ◽  
Sujung Han ◽  
Talitha Santini ◽  
Gurkiran Kaur ◽  
Dean W. Johnstone ◽  
...  
Keyword(s):  
Oxalic Acid ◽  
Inductively Coupled Plasma ◽  
Bauxite Residue ◽  
Soil Formation ◽  
Optical Emission ◽  
Vegetation Coverage ◽  
Dissolution Mechanism ◽  
Negative Effects ◽  
Alumina Industry ◽  
Bauxite Residues

Environmental context Although land remediation programs for bauxite residues aim at vegetation coverage, the stability of compounds in the residues with acids produced by the vegetation has not been investigated. We show that, despite the instability of caustic components in the residues (negative effects on plant development), this instability actually assists in neutralising acidic soils. These results further affirm the suitability and sustainability of current land remediation programs for bauxite residues in terms of minimising acidic soil formation. Abstract This investigation used a combination of techniques, such as X-ray diffraction, inductively coupled plasma optical emission spectroscopy and infrared spectroscopy, to determine the dissolution mechanisms of the Bayer precipitate and the associated rate of dissolution in acetic, citric and oxalic acid environments. The Bayer precipitate is a mixture of hydrotalcite, calcium carbonate and sodium chloride that forms during the seawater neutralisation of Bayer liquors (waste residue of the alumina industry). The dissolution rate of a Bayer precipitate is found to be dependent on (1) the strength of the organic acid and (2) the number of donating H+ ions. The dissolution mechanism for a Bayer precipitate consists of several steps involving: (1) the dissolution of CaCO3, (2) formation of whewellite (calcium oxalate) when oxalic acid is used and (3) multiple dissolution steps for hydrotalcite that are highly dependent on the pH of solution. The decomposition of the Al–OH hydrotalcite layers resulted in the immediate formation of Al(OH)3, which is stable until the pH decreases below 5.5. This investigation has found that the Bayer precipitate is stable across a wide pH range in the presence of common organic acids found in the rhizosphere, and that initial decomposition steps are likely to be beneficial in supporting plant growth through the release of nutrients such as Ca2+ and Mg2+.

Contributions to the Knowledge of Sandy Soils from Oltenia Plain

2020 ◽  
Vol 71 (1) ◽  
pp. 192-200
Author(s):  
Anca-Luiza Stanila ◽  
Catalin Cristian Simota ◽  
Mihail Dumitru
Keyword(s):  
Chemical Properties ◽  
Soil Formation ◽  
Sandy Soils ◽  
Physical Geography ◽  
Parent Material ◽  
Negative Effects ◽  
Small Water ◽  
Wind Characteristic ◽  
The One ◽  
Physical And Chemical

Highlighting the sandy soil of Oltenia Plain calls for a better knowledge of their variability their correlation with major natural factors from each physical geography. Pedogenetic processes specific sandy soils are strongly influenced by nature parent material. This leads, on the one hand, climate aridity of the soil due to strong heating and accumulation of small water reserves, consequences emphasizing the moisture deficit in the development of the vegetation and favoring weak deflation, and on the other hand, an increase in mineralization organic matter. Relief under wind characteristic sandy land, soil formation and distribution has some particularly of flat land with the land formed on the loess. The dune ridges are less evolved soils, profile underdeveloped and poorly supplied with nutrients compared to those on the slopes of the dunes and the interdune, whose physical and chemical properties are more favorable to plant growth.Both Romanati Plain and the Blahnita (Mehedinti) Plain and Bailesti Plain, sand wind shaped covering a finer material, loamy sand and even loess (containing up to 26% clay), also rippled with negative effects in terms of overall drainage. Depending on the pedogenetic physical and geographical factors that have contributed to soil cover, in the researched were identified following classes of soils: protisols, cernisols, cambisols, luvisols, hidrisols and antrosols.Obtaining appropriate agricultural production requires some land improvement works (especially fitting for irrigation) and agropedoameliorative works. Particular attention should be paid to preventing and combating wind erosion.

Historical Footnote—Factors of Soil Formation

Soil Horizons ◽  
1992 ◽  
Vol 33 (3) ◽  
pp. 70 ◽  
Author(s):  
Simonson Roy W.
Keyword(s):  
Soil Formation ◽  
Factors Of Soil Formation

Microclimate and Soil Formation

Soil Horizons ◽  
1981 ◽  
Vol 22 (4) ◽  
pp. 20
Author(s):  
H. R. Finney
Keyword(s):  
Soil Formation

Soil and ecological division into districts of the Baikal region

2018 ◽  
Vol 940 (10) ◽  
pp. 54-64 ◽  
Author(s):  
I.A. Belozertseva ◽  
A.A. Sorokovoj
Keyword(s):  
Baikal Region ◽  
Soil Cover ◽  
Soil Formation ◽  
Forest Steppe ◽  
Leading Role ◽  
Soil Cover Structure ◽  
Reflecting Surface ◽  
Heat And Moisture ◽  
Made In

On the basis of long-term researches of soils in the territory of Russia and Mongolia soil and ecological division into districts of the Baikal region is carried out. At division into districts the whole set of an environment of soil formation was considered. On the map of soil and ecological division into districts 13 mountain, mid-mountain, low-mountain taiga, foothill, hollow-valley, forest-steppe and steppe provinces reflecting surface device originality as the ratio of balance of heat and moisture forming a basis to zoning is shown against the background of difficult orography are allocated. In total 42 districts on lithologic-geomorphological features are allocated. In formation of distinctions of a soil cover of these provinces the leading role is played by bioclimatic factors and inside them the lithologic-geomorphological ones. In the view of structural approach of the district they are considered as territories with a certain natural change of several types of the soil cover structure caused by features of a relief and the parent rock. The map is made in the MapInfo program. It is revealed that on ill-defined width zoning of soils the vertical one which has a greater influence on soils of this region is imposed. Soils of the Baikal region are not similar to the soils located at the same latitude of the flat European territory of Russia. Zone soils of this territory are specific and original.

Sign in / Sign up

Export Citation Format

Share Document