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M. A. R. S. Shazana J. Shamshuddin C. I. Fauziah S. R. Syed Omar 《Land Degradation \u0026amp; Development》2013,24(2):129-140
A study was conducted into the alleviation of the infertility of an acid sulphate by using ground basalt with or without ground magnesium limestone (GML) and organic fertilizer. Fresh soils were treated with the amendments and subjected to two cycles of submergence and drying. The soil was dominated by kaolinite, mica and smectite. The untreated soil pH was <3·5 and solution Al was high. GML application at 4 t ha−1 was able to increase pH and subsequently reduced Al toxicity sufficiently to allow for rice growth. After 4 months of submergence, the pH of the sample treated with 4 t ground basalt ha−1 had increased from 3·61 to 3·94, with concomitant decrease of Al. In the same cycle, the soil pH increase was much higher (reaching 5·22). Ground basalt is thus comparable with GML as an acid soil ameliorant. Within the experimental period, the ground basalt had mostly disintegrated and dissolved. The solution pH had further increased (to 5·94) in the second cycle because of dissolution of more ground basalt. This means that it takes time for ground basalt to completely dissolve and consequently supply Ca, Mg, K and P to the growing crop in the field. Applying 0·25 t organic fertilizer ha−1 into the soil had no significant effect on either pH or Al. This form of organic matter (compost) contains essential nutrients. It is recommended that 4 t ground basalt should be applied in combination with 0·25 t organic fertilizer ha−1 a few months ahead of the growing season for maximal benefit. This study showed that ground basalt can be effectively used to ameliorate highly acidic soils. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Dian Fiantis Malik Nelson Jusop Shamshuddin Tee Boon Goh Eric Van Ranst 《Communications in Soil Science and Plant Analysis》2016,47(15):1792-1812
To date, no global data on carbon sequestration at the initial weathering phase of tephra deposits are available. To study carbon storage in the new volcanic deposit, tephra layers were reconstructed for a period of 46 months. The tephra samples were collected immediately after eruption of Mount (Mt.) Talang on 12 April 2005, over portions of the Solok District in West Sumatra, Indonesia. Pot experiments were filled with and without soil materials and covered with the collected tephra. The pot experiments were conducted in a wired house. The tephra was applied in 0, 2.5 and 5 cm depths to simulate natural tephra deposition. Every day 250 ml of filtered water was added and allowed to percolate. Solid fraction from the tephra layer was collected and analyzed at regular intervals and primary plant succession was observed over a period of 4 years. After 2 months, blue-green algae (cyanobacteria) started to colonize the bare surface tephra layer to form an algae mat. After 16 months, the surface was transformed into a green biofilm of lichen. Vascular plants (grasses and shrubs) started to be established after 2 years. Total carbon (TC) content of the tephra layer was increased significantly from 0.19 to 1.75% or eight times higher after 46 months of incubation. Higher TC storage was found in the 2.5 cm compared to that of the 5.0 cm tephra layer, which was reconstructed above the soil, with values of 1.75 and 0.89%, respectively. On the contrary, lesser amount of TC was accumulated in the single tephra layer (without soil underneath). Between 71 and 90% of TC was considered as total organic carbon (TOC). The labile organic carbon (LOC) content in the 2.5 cm and 5.0 cm of tephra layer was found to be 0.22 and 0.77%, respectively, at the end of incubation. This experiment confirmed the potential of tephra to capture carbon from the atmosphere with the help of nonvascular plants and then by vascular plants and finally sink them in the tephra layer. 相似文献
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Three Oxisols, developed from serpentinite (Sungai Mas Series), basalt (Kuantan Series) and andesite (Segamat Series), selected to represent the most common Oxisols in Malaysia were sampled and studied. The objectives of this study were: (i) to determine mineralogical composition and factors responsible for changes in point of zero charge (pH0) of the variable charge component of three Oxisols; (ii) to use pH0 values to assess degree of chemical weathering; and (iii) to determine the magnitude of variable charge using corrected back-titration technique. The mineralogical composition was determined by X-ray diffraction analysis (XRD). The pH0 was determined by potentiometric titration in different electrolyte strengths. The magnitude of variable charge generation as a function of soil pH was measured using corrected back-titration to allow elimination of charge overestimation caused by solid dissolution and hydrolysis reactions. The results showed that the mineralogical composition were similar (kaolinite, goethite, hematite and gibbsite) between profiles but different in proportion, except for gibbsite which was absent in the andesite-derived soil. The sequential removal of soil organic matter (SOM), iron oxides and SOM together with iron oxides resulted in the changes of pH0 from 3.9–5.7 to 5.3–6.7, 2.6–3.7 and 3.3–4.5, respectively. These pH0 changes indicate SOM and sesquioxides are masking mineral surfaces and are factors responsible for lowering and increasing pH0 values, respectively. Regression correlation (R2 = 0.87??) showed that for every 1% organic C may decrease 1.0 unit of pH0 value. The pH0 values, after SOM removal, are in the order of Sungai Mas ～ Segamat > Kuantan Series. This suggests that the serpentinite and andesite-derived soils have achieved a relatively similar degree of chemical weathering and they are more weathered than the basalt-derived soil. The charge measured by corrected back-titration is 1.5–3.8 cmolc kg? 1 at pH 4.5 and increases to 4.2–10.8 cmolc kg? 1 at pH 6.5, indicating that the three Oxisols mainly bear variable charge. Charge overestimation resulted from dissolution and hydrolysis reactions during potentiometric titration ranges from 36 to 160%, depending on pH values (the lower the pH the higher is the overestimation). Hence, back-titration is a reliable technique to correct charge overestimation when using the traditional potentiometric titration for highly weathered tropical soils. 相似文献
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A study was conducted to determine the extend of volcanic ash deposition and distribution in some soils of Malaysia. A total of 12 soil types of different geology and locations from Peninsular Malaysia and West Sarawak were collected and analysed for their physico‐chemical and dissolution analysis. All soils under study belonged to either the order of Inceptisols, Ultisols or Oxisol. They were acidic and had relatively low CEC and exchangeable bases. The Al saturation percent were higher in the Ultisols as compared to the Oxisols. Field and laboratory investigations, and the dissolution analysis comprising of the binary ratio, ferrihydrite percent and allophane content, suggested that the soils under study were highly weathered and non‐allophanic. The soils of West Sarawak, however, may contain a reasonable deposits of the volcanic ash materials, as shown by the higher pHNaF values of near 9.4, but other laboratory analysis were still not conclusive of the result. 相似文献
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D. Fiantis M. Nelson J. Shamshuddin T. B. Goh E. Van Ranst 《Eurasian Soil Science》2010,43(13):1477-1485
Since the Indonesian archipelago is part of the very active and dynamic Pacific Ring of Fires, the volcanic eruptions occur
from time to time. Immediately after the eruption of Mount Talang in West Sumatra (April 12, 2005), volcanic ashes, both unleached
and leached were collected. The deposits from Mt. Talang were andesitic to basaltic in composition. The volcanic ash consisted
of volcanic glass, plagioclase feldspar in various proportions, orthopyroxene, clinopyroxene, olivine, amphibole, titanomagnetite.
We conducted the total elemental analysis of the bulk samples of the volcanic ash. The contents of major, trace and rare elements
as well as heavy metals were determined by wet chemical methods and x-ray fluorescence (XRF) analyses. Although the volcanic
ash of Mt. Talang are still very new, an evaluation of the geochemical weathering indices was performed with the objective
of showing the volcanic ash condition at the early stage of weathering. Eight weathering indices were evaluated. The results
showed that the unleached volcanic ash has higher Ruxton Ratio (R), Weathering Index of Parker (WIP), Product of Weathering
Index (PWI) and Silica Titanium Index (STI) values compared to the leached ash, while the leached ash exhibited higher Chemical
Index of Alteration (CIA), Chemical Index of Weathering (CIW), Vogt’s Residual Index (VO), and Plagioclase Index of Alteration
(PIA). These weathering indices can be used to quantify the condition of the volcanic ashes at the initial stage of weathering,
to evaluate their fertility, to provide a better understanding of element mobility during weathering, and predict the source
of soil nutrients as well as determine the products of primary minerals alteration. 相似文献
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