Optimisation of Charcoal and Sago (Metroxylon sagu) Bark Ash to Improve Phosphorus Availability in Acidic Soils

Soil acidity is an important soil factor affecting crop growth and development. This ultimately limits crop productivity and the profitability of farmers. Soil acidity increases the toxicity of Al, Fe, H, and Mn. The abundance of Al and Fe ions in weathered soils has been implicated in P fixation. To date, limited research has attempted to unravel the use of charcoal with the incorporation of sago (Metroxylon sagu) bark ash to reduce P fixation. Therefore, an incubation study was conducted in the Soil Science Laboratory of Universiti Putra Malaysia Bintulu Sarawak Campus, Malaysia for 90 days to determine the optimum amounts of charcoal and sago bark ash that could be used to improve the P availability of a mineral acidic soil. Charcoal and sago bark ash rates varied by 25%, whereas Egypt rock phosphate (ERP) rate was fixed at 100% of the recommendation rate. Soil available P was determined using the Mehlich 1 method, soil total P was extracted using the aqua regia method, and inorganic P was fractionated using the sequential extraction method based on its relative solubility. Other selected soil chemical properties were determined using standard procedures. The results reveal that co-application of charcoal, regardless of rate, substantially increased soil total carbon. In addition, application of 75% sago bark ash increased soil pH and at the same time, it reduced exchangeable acidity, Al3+, and Fe2+. Additionally, amending acidic soils with both charcoal and sago bark ash positively enhanced the availability of K, Ca, Mg, and Na. Although there was no significant improvement in soil Mehlich-P with or without charcoal and sago bark ash, the application of these amendments altered inorganic P fractions in the soil. Calcium-bound phosphorus was more pronounced compared with Al-P and Fe-P for the soil with ERP, charcoal, and sago bark ash. The findings of this study suggest that as soil pH decreases, P fixation by Al and Fe can be minimised using charcoal and sago bark ash. This is because of the alkalinity of sago bark ash and the high affinity of charcoal for Al and Fe ions to impede Al and Fe hydrolysis to produce more H+. Thus, the optimum rates of charcoal and sago bark ash to increase P availability are 75% sago bark ash with 75%, 50%, and 25% charcoal because these rates significantly reduced soil exchangeable acidity, Al3+, and Fe2+.

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Effects of Organic and Inorganic Materials on Soil Acidity and Phosphorus Availability in a Soil Incubation Study

ISRN Agronomy ◽

10.5402/2012/597216 ◽

2012 ◽

Vol 2012 ◽

pp. 1-10 ◽

Cited By ~ 20

Author(s):

P. A. Opala ◽

J. R. Okalebo ◽

C. O. Othieno

Keyword(s):

Soil Ph ◽

Phosphate Rock ◽

Farmyard Manure ◽

Inorganic Materials ◽

P Availability ◽

Soil Fertility Management ◽

Inorganic P ◽

Exchangeable Acidity ◽

Incubation Study ◽

P Sources

We tested the effects of two organic materials (OMs) of varying chemical characteristics that is, farmyard manure (FYM) and Tithonia diversifolia (tithonia), when applied alone or in combination with three inorganic P sources, that is, triple superphosphate (TSP), Minjingu phosphate rock (MPR), and Busumbu phosphate rock (BPR) on soil pH, exchangeable acidity, exchangeable Al, and P availability in an incubation study. FYM and tithonia increased the soil pH and reduced the exchangeable acidity and Al in the short term, but the inorganic P sources did not significantly affect these parameters. The effectiveness of the inorganic P sources in increasing P availability followed the order, TSP > MPR > BPR, while among the OMs, FYM was more effective than tithonia. There was no evidence of synergism in terms of increased available P when organic and inorganic P sources were combined. The combination of OMs with inorganic P fertilizers may, however, have other benefits associated with integrated soil fertility management.

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Amending Potassic Fertilizer with Charcoal and Sago (Metroxylon sagu) Bark Ash to Improve Potassium Availability in a Tropical Acid Soil

Agronomy ◽

10.3390/agronomy11112222 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2222

Author(s):

Puvan Paramisparam ◽

Osumanu Haruna Ahmed ◽

Latifah Omar ◽

Huck Ywih Ch’ng ◽

Ali Maru ◽

...

Keyword(s):

Soil Ph ◽

Acid Soil ◽

Chemical Properties ◽

Water Soluble ◽

Soil Chemical Properties ◽

Kaolinite Clay ◽

Exchangeable K ◽

Exchangeable Acidity ◽

Metroxylon Sagu ◽

Sago Bark

In Ultisols and Oxisols, potassium (K) in the soil solution is leached from the rhizosphere before it interacts with soil colloids, or exchanged with other cations at the exchange sites of the soils because of the abundance of kaolinite clay minerals. These soils are highly weathered, low in organic matter, and low in pH, but high aluminium (Al) and iron (Fe) ions. Hence, K becomes unavailable for plants, and this compromises crop production and farmers’ profitability. The pH neutralizing effects of sago (Metroxylon sagu) bark ash and the ability of charcoal to chelate Al and Fe could be utilized to improve soil pH, reduce soil acidity, and improve K availability. The objective of this study was to determine the effects of amending muriate of potash (MOP) with charcoal and sago bark ash on selected soil chemical properties in a tropical acid soil (Typic Paleudults) over 90 days in a laboratory incubation. The proportions of charcoal and sago bark ash were varied at 20%, 40%, 60%, 80%, and 100%, but the MOP was fixed at 100% of the recommended rate. Selected soil chemical properties before and after incubation were determined using standard procedures. Results revealed that co-application of the soil amendments with MOP increased soil-exchangeable K compared with conventional practice. Moreover, amending the acid soil with charcoal and sago bark ash positively enhanced the availability of other base cations and soil cation exchange capacity (CEC). This was possible because the amendments increased soil pH and reduced exchangeable acidity, exchangeable Al3+, and exchangeable Fe2+. However, there was no significant improvement in water-soluble K (WSK) in the soil with or without charcoal and sago bark over the 90 days laboratory study. The findings of this study suggested that increasing soil pH could potentially improve soil K sorption capacity. Thus, the optimum rates of charcoal and sago bark ash to increase K availability were found to be 80% charcoal with 80% sago bark ash, 60% charcoal with 60% sago bark ash, and 80% charcoal with 40% sago bark ash, because these rates improved soil-exchangeable K+ and CEC significantly, besides minimizing soil-exchangeable acidity.

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Charcoal and Sago Bark Ash on pH Buffering Capacity and Phosphorus Leaching

Agronomy ◽

10.3390/agronomy11112223 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2223

Author(s):

Prisca Divra Johan ◽

Osumanu Haruna Ahmed ◽

Latifah Omar ◽

Nur Aainaa Hasbullah

Keyword(s):

Soil Ph ◽

Acid Soils ◽

Mineral Acid ◽

Buffering Capacity ◽

P Availability ◽

Exchangeable Acidity ◽

Ph Buffering ◽

P Leaching ◽

Sago Bark ◽

Ph Buffering Capacity

Soil-available P for crop use is limited because of fixation reaction and loss of organic matter through erosion and surface runoff. These factors cause an imbalance between inputs and outputs of P nutrients in acid soils. Several approaches to improve P availability have been proposed, however, little is known about the effectiveness of amending humid mineral acid soils with charcoal and sago bark ash on P dynamics. Thus, pH buffering capacity and leaching studies were conducted to determine: (i) pH buffering capacity upon application of charcoal and sago bark ash and (ii) the influence of charcoal and sago bark ash on P leaching in acid soils. pH buffering capacity was calculated as the negative reciprocal of the slope of the linear regression (pH versus acid addition rate). A leaching study was carried out by spraying distilled water to each container with soil such that leachates through leaching were collected for analysis. The ascending order of the treatments based on their pH buffering capacity and regression coefficient (R2) were soil alone (0.25 mol H+ kg−1 sample), soil with charcoal (0.26 mol H+ kg−1 sample), soil with sago bark ash (0.28 mol H+ kg−1 sample), charcoal alone (0.29 mol H+ kg−1 sample), soil with charcoal and sago bark ash (0.29 mol H+ kg−1 sample), and sago bark ash alone (0.34 mol H+ kg−1 sample). Improvement in the soil pH buffering capacity was partly related to the inherent K, Ca, Mg, and Na contents of charcoal and sago bark ash. In the leaching study, it was noticed that as the rate of sago bark ash decreased, the pH of leachate decreased, suggesting that unlike charcoal the sago bark ash has significant impact on the alkalinity of leachate. Soil exchangeable acidity, Al3+, and H+ reduced significantly following co-application of charcoal and sago bark ash with ERP. This could be attributed to the neutralizing effects of sago bark ash and the high affinity of charcoal for Al and Fe ions. The amount of P leached from the soil with 100% charcoal was lower because charcoal has the ability to capture and hold P-rich water. The findings of this present study suggest that combined use of charcoal and sago bark ash have the potential to mitigate soil acidity and Al toxicity besides improving soil pH buffering capacity and minimizing P leaching. A field trial to consolidate the findings of this work is recommended.

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Modifications of phosphorus in Latosol as a function of humic acids and acidity

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v22n7p488-492 ◽

2018 ◽

Vol 22 (7) ◽

pp. 488-492 ◽

Cited By ~ 1

Author(s):

Márcia H. Beck ◽

Pedro A. V. Escosteguy ◽

Deborah P. Dick

Keyword(s):

Factorial Design ◽

Humic Acids ◽

Soil Ph ◽

Crucial Role ◽

Soil Acidity ◽

Ph Value ◽

P Availability ◽

Soil P ◽

P Content

ABSTRACT The effect of humic acids (HA) on phosphorus (P) availability is still contradictory; thus, it is necessary to identify the conditions that play a crucial role in this effect. The aim of this study was to investigate the effect of HA application, combined with doses of P, on the content of this nutrient in a Latosol with and without acidity correction. Two experiments were carried out, one with HA from peat and another with HA from mineral charcoal (leonardite). Doses of these acids (0; 1.12 and 5.62 mg C g-1 of soil) and P (26.2 and 104.7 mg P g-1 of soil, 1 and 4-fold higher than recommended, respectively) were tested at soil pH 4.5 and 7.0, in a three-factorial design. The soil was incubated for 20 days and the soil-P content was measured by Mehlich-1 and remaining-P tests. The effect of HAs on P availability varied with the P doses and soil acidity. Humic acids application increases P content in Latosol when P dose is higher than recommended and there is no acidity correction (pH 4.5). However, there is no effect of HAs application on soil-P content when applying the recommended amount of this nutrient, irrespective of the pH value.

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Combined Use of Charcoal, Sago Bark Ash, and Urea Mitigate Soil Acidity and Aluminium Toxicity

Agronomy ◽

10.3390/agronomy11091799 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1799

Author(s):

Nur Hidayah Hamidi ◽

Osumanu Haruna Ahmed ◽

Latifah Omar ◽

Huck Ywih Ch'ng

Keyword(s):

Soil Acidity ◽

Chemical Properties ◽

Aluminium Toxicity ◽

N Availability ◽

Soil N ◽

Total N ◽

Soil N Availability ◽

Exchangeable Acidity ◽

Combined Use ◽

Sago Bark

Highly weathered tropical acidic soils are characterized by low pH, low organic matter, and aluminium and iron toxicity. These factors pose a challenge to achieving sustainable agriculture. The continued increase in the human population with the accompanied increasing food demand have negatively impacted the global N cycle partly because of excessive use N fertilizers particularly urea which is commonly used in agriculture. Ammonia volatilization from urea as an example, negatives the environmental quality. This study focuses on soil-N availability, pH, exchangeable acidity, Al3+, and H+ of a highly weathered acid soils (Bekenu series) through the combined use of charcoal, sago bark ash, and urea. To this end, an incubation study was conducted for 90 days through the combined use of charcoal, sago bark ash, and urea to determine if this approach could improve soil N availability and pH at the same time reducing exchangeable acidity, and Al3+, and H+ toxicity. The amount of urea used was fixed at 100% as the recommended rate. Charcoal and sago bark ash were varied by 25%, 50%, 75%, and 100%, respectively of the recommended rate. Selected soil physico-chemical properties were determined using standard procedures. This study revealed that combined use of charcoal, sago bark ash, and urea increased soil pH and base cations simultaneously the approach also reduced exchangeable acidity, exchangeable Al3+, and exchangeable H+. There were no significant differences in soil total N, exchangeable NH4+, and available NO3− for the combined use of charcoal, sago bark ash, and urea and urea alone because of the acid neutralizing effect of the amendments. Apart from the sago bark ash’s liming effect, the high affinity of the functional groups of the charcoal for Al3+ might have impeded Al3+ from undergoing hydrolysis to produce more H+ because a complete one mole of Al3+ hydrolysis produces three moles of H+. Thus, the combined use of charcoal and sago bark ash can mitigate soil acidity and aluminium toxicity, although this approach has minimal effect on-N.

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Rising levels of soil acidity in Meghalaya: Evidences and Imperatives

ANNALS OF PLANT AND SOIL RESEARCH ◽

10.47815/apsr.2021.10073 ◽

2021 ◽

Vol 23 (3) ◽

pp. 297-303

Author(s):

MANOJ KUMAR ◽

Keyword(s):

Soil Acidity ◽

Principal Component ◽

Northeast India ◽

Mean Value ◽

Current Status ◽

Acidic Soils ◽

Exchangeable Acidity ◽

Exchangeable Al ◽

Eigen Values ◽

Garo Hills

In order to examine the current status of soil acidity in Meghalaya, representative soil samples (n= 497) were collected (during 2015-2016) from across the state and analyzed for soil acidity and associated parameters. Averaged across the samples, pH of the soils was found to be very strongly acidic (4.94). Nearly 20 % of the soils had pH below 4.50, 59% below pH 5.0 and 80% below pH 5.50. Only 3.4% of the samples recorded pH more than 6.0. East Khasi Hills District had the maximum percentage (95.1%) of strongly acidic soils (pH ≤ 5.50) while Garo Hills had the least (50.2%). All other districts recorded more than 85% of the strongly acidic soils. Average exchangeable acidity, exchangeable Al and effective CEC were found to be 1.60, 1.27 and 3.86 meq/100g soil, respectively. Mean base saturation was recorded below 60%. Aluminium saturation (percentage of effective CEC being occupied by exch. Al) ranged from 1.5 to 79.7% with its mean value being as high as 33%. Principal component analysis provided three PCs with Eigen values >1 and together they explained 83.2 % of the variance in total dataset. The soil acidity in Meghalaya is on rise, with 80.2% of its soils being strongly acidic (pH ≤ 5.50) in contrast to the previous reports of 53% soils being strongly acidic. This calls for widespread adoption of soil acidity ameliorative measures in agriculture of Meghalaya, Northeast India.

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Cattle manure and lime amendments to improve crop production of acidic soils in Northern Alberta

Canadian Journal of Soil Science ◽

10.4141/s01-030 ◽

2002 ◽

Vol 82 (2) ◽

pp. 227-238 ◽

Cited By ~ 15

Author(s):

Joann K Whalen ◽

Chi Chang ◽

George W Clayton

Keyword(s):

Soil Ph ◽

Crop Production ◽

Soil Acidity ◽

Agricultural Land ◽

Wheat Yield ◽

Acid Soils ◽

Cattle Manure ◽

Acidic Soils ◽

Available N ◽

Micronutrient Uptake

Crop production on acid soils can be improved greatly by adjusting the pH to near neutrality. Although soil acidity is commonly corrected by liming, there is evidence that animal manure amendments can increase the pH of acid soils. Fresh cattle manure and agricultural lime were compared for their effects on soil acidity and the production of canola (Brassica napus L.) and wheat (Triticum aestivum L.) in a greenhouse study. Canola and wheat yield, the nutrient content of grain and straw, and selected soil properties were determined on a Gray Luvisol (pH 4.8) from the Peace Region of Alberta. Soil pH increased with lime and manure applications, and canola and wheat yields were higher in limed and manure-amended soils than unfertilized, unlimed soils. Macronutrient uptake by canola and wheat was generally improved by liming and manure applications, and micronutrient uptake was related to the effects of lime and manure on soil pH. An economic analysis compared the costs of using cattle manure and lime to increase soil pH to 6.0. The costs of applying lime and fresh cattle manure to increase soil pH were compared, based on the fees for purchasing and applying lime or loading, hauling and applying manure. The nutrient value of manure was calculated based on the quantities of plant-available N, P and K in fresh manure. At distances less than 40 km, it is economical to substitute fresh cattle manure for agricultural lime to increase soil pH of acidic soils. However, good manure management practices should be followed to minimize the risk of nutrient transport and environmental pollution from agricultural land amended with cattle manure. Key words: Agricultural economics, canola production, cattle manure, lime, soil pH, wheat prodution

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Extent, Distribution, and Causes of Soil Acidity under Subsistence Farming System and Lime Recommendation: The Case in Wolaita, Southern Ethiopia

Applied and Environmental Soil Science ◽

10.1155/2021/5556563 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Fanuel Laekemariam ◽

Kibebew Kibret

Keyword(s):

Soil Fertility ◽

Soil Ph ◽

Soil Acidification ◽

Soil Acidity ◽

Farmyard Manure ◽

Southern Ethiopia ◽

Subsistence Farming ◽

Exchangeable Acidity ◽

Management Interventions ◽

Exchangeable Al

Soil acidity is one of the most important environmental threats to the Ethiopian highlands where the livelihood of the majority of people is reliant on agriculture. Yet, information regarding its extent, distribution, causes, and lime requirement at a scale relevant to subsistence farming systems is still lacking. This study (1) investigates the extent and spatial distribution of soil acidity, (2) identifies factors attributing to soil acidification, and (3) predicts the lime requirement for major crops. A total of 789 soil samples were collected from arable lands in the Wolaita area which is mainly characterized by poor soil fertility and soil degradation in southern Ethiopia. Results revealed that the landscape is characterized by a gentle slope followed by strongly sloppy > flat > hilly topographies. Clay is the dominant soil textural class. A soil pH map, which is generated using geospatial analysis, demonstrates that 3.3, 78.0, and 18.7% of the total area were under strongly acidic, moderately acidic, and neutral soil reactions, respectively. The exchangeable acidity (Cmol(+)/kg) varied from nil to 5.1, whereas exchangeable Al ranged from 1.4 to 19.9 Cmol(+)/kg. The soil pH has shown a significantly ( p < 0.001) negative association with clay content (r = −0.33), exchangeable Al (r = −61), exchangeable acidity (r = −0.58), and inorganic fertilizer application (r = −0.33). Increased rates of diammonium phosphate (DAP) (r2 = 0.91) and urea (r2 = 0.88) markedly elevated soil acidity. Conversely, manuring showed a significant ( p < 0.001) and positive relationship with pH (r = 0.37) in which the increasing rate of manure significantly reduced acidification (r2 = 0.98). DAP and urea applications above 75 kg/ha lowered soil pH units by 0.56 and 0.48, respectively, <25 kg/ha while at the same time farmyard manure (FYM) at 4 t/ha raised pH by 0.75 units over the unfertilized field. Residue management significantly ( p < 0.001) influenced soil pH wherein it ranged from 6.09 (complete residue removal) to 6.61 (residue incorporation). Changes in land use, cropping intensity, and socioeconomic status were also significantly attributed to soil acidification. To curb the effects of soil acidity, the lime requirement for common bean growing fields varied from zero to 6.6 t/ha, while for maize it was between zero and 4.3 t/ha. It is concluded that soil management interventions such as maintaining and incorporating crop residues, integrated use of organic and inorganic fertilizers, liming, and enhancing farmers’ awareness should be advocated to overcome soil acidification and improve soil fertility. In addition, introducing crops with traits that tolerate acidity and Al toxicity is also suggested.

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Soils Acidity Characterization, Mapping and Lime Recommendation of Jimma Arjo District, East Wollega Zone of Oromia Region, Ethiopia

10.21203/rs.3.rs-637000/v1 ◽

2021 ◽

Author(s):

Fayisa Olana Bulo ◽

Hailu Shiferaw Desta

Keyword(s):

Soil Fertility ◽

Soil Acidity ◽

Nutrient Status ◽

Soil Reaction ◽

Acidic Soils ◽

Exchangeable Acidity ◽

The Difference ◽

Analytical Services ◽

The Right

Abstract Background: Soil fertility is one of the major constraints of agricultural production and productivity. Soil fertility atlas shows plant nutrient status and is useful for decision making in fertilizers and other amendments advisory service for farmers. The objectives of this research were to study the farming activity, assess the acidity status of the soils, map and recommend the right amount of lime for acidic soils. Result: A total of 199 soil samples were collected across Jimma Arjo district at 1.5 km grid interval from a depth of 0 - 20 cm for annual and 0 - 50 cm for perennial crops. The total area of the district was 76,574 ha. Soil reaction (pH), electrical conductivity (EC) and exchangeable acidity (EA) were done at Nekemte Soil Research Center. Exchangeable bases (Ca, Mg, K, Na) were analyzed by wet chemistry analysis at Yara Analytical Services, England. Critical levels adopted by the Ethiopian Soil Information System (EthioSIS) project were used for characterization of the soil properties. Soil reaction (pH) ranged from 4.45 to 6.87 in which 17.1 and 78.4% of the total area was covered by strongly acidic soils and slightly acidic soils, respectively. Agricultural lime (Ag-lime) was required for 17.87% of the total area and 12.63%, 4.36% and 0.88% of the total area require lime at a rate of 0 - 1, 1 - 2, and 2 - 4.1 tons/ha respectively. Conclusion: The highland areas of the district are more populated and there is high pressure on soil, cooler temperature and higher rainfall than lowlands which resulted in soil acidity of the highlands. The magnitude and extent of soil acidity in the area is expanding and liming is very important as an entry point to mitigate further expansion. The observed dependency of the soil acidity on landscape position could be a proxy indicator of the difference in fertility status of the two landscapes.

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The Effect of pH on Phosphorus Adsorption in Acidic Soils of Tsegede, Western Zone of Tigray, Ethiopia

10.21203/rs.3.rs-54755/v1 ◽

2020 ◽

Author(s):

Haile Alene Tareke ◽

Gebreyohannes Girmay Woldetensai ◽

fisseha Hadgu Birhane

Keyword(s):

Adsorption Isotherm ◽

Soil Ph ◽

Available P ◽

Dihydrogen Phosphate ◽

P Availability ◽

Acidic Soils ◽

Phosphorus Adsorption ◽

P Adsorption ◽

Langmuir Adsorption ◽

Adsorption Characteristics

Abstract Background: Although soils in the acidic soils of Tsegede (Skeletic Leptosols, Cambic Leptosols, Leptic Cambisols and Dystric Cambisols) are characterized by low available P contents, study on P adsorption characteristics is limited information. The purpose of this experiment was to evaluate P adsorption characteristics in different acidity ranges of soils. Material and method: Potassium dihydrogen phosphate (KH2PO4) was used for the adsorption isotherm studies by duplicating 3 g soil from each soil types at different acidity ranges of ten soil samples with 50 ml of P in 0.01 M CaCl2 solution having 0, 20, 40, 60, 80,100 mg P L-1. Langmuir and Freundlich adsorption isotherm models were used to describe adsorption processes and the relationships between P adsorption and soil properties were determined by correlation. Results: Phosphorus adsorption increased significantly with increasing P levels and it increased as soil pH declines. The maximum and minimum P-adsorptions were obtained from very strongly acidic Skeletic Leptosols and from moderately acidic Dystric Cambisols, respectively. Comparing the two models, Langmuir linear model showed a better fit to the tested soils compared to Freundlich model. The regression coefficients (R2) for the fitted Langmuir P adsorption isotherms were highly significant ranging from (0.955 to 0.999) and the adsorption maxima obtained from the Langmuir isotherm ranged from 357 mg P kg-1 soil in strongly acidic Dystric Cambisols to 2500 mg P kg-1 soil in very strongly acidic Skeletic Leptosols. The bonding energy (k) for Langmuir adsorption model varied from 0.012 to 2.8 L mg-1 and both the highest (2.8 L mg-1) and lowest (0.012 L mg-1) k values were obtained from strongly and moderately acidic Dystric Cambisols. The cation exchange capacity (CEC) and organic carbon (OC) were positively correlated with the Langmuir adsorption maxima (b) and negatively correlated with available P and soil pH. Conclusion: Increments of soil pH using different amendments and their proper management in soils are important in making productive use and higher dose of P is required by soils with higher fixation. Alternative P management strategies are also needed to reduce P adsorption and enhance P availability in such acidic soils in the study areas.

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