Phosphorus Transformation in Soils Following Co-Application of Charcoal and Wood Ash

Abstract

Phosphorus (P) is a vital soil macronutrient required by plants for optimum growth and development. However, its availability is limited because of fixation. The phosphorus fixation reaction is pH dependent. In acid soils, the predominance of aluminium (Al) and iron (Fe) oxides in both crystalline and amorphous forms reduces the solubility of soil inorganic P through fixation on positively charged surfaces and formation of insoluble Al and Fe precipitates. In alkaline soils, P readily reacts with calcium (Ca) to form sparingly soluble calcium phosphates. As a result, a large proportion of applied P may become chemically bound, whereas only a small fraction of soil P remains in the soil solution and available for plant uptake. To date, there is little information available on the use of charcoal with a highly negative charge and wood ash with high alkalinity to minimise P fixation in acid soils. Thus, this study examined the potential of the combined use of charcoal and wood ash to unlock P fixation in acid soils. Numerous studies have been conducted to identify effective approaches to improve P availability through the use of different types of soil amendments, regardless of whether P is organically or inorganically present. For example, to mitigate P fixation in acid soils, amendments such as compost and zeolite are used to reduce P sorption sites. These amendments have also been used to increase P uptake and crop productivity in P deficient acid soils by reducing soil acidity and the toxicity of Al and Fe. It is believed that long-term application of charcoal and sago bark ash can positively change the physical and chemical properties of soils. These improvements do not only reduce P fixation in acid soils, but they also promote an effective utilisation of nutrients through timely release of nutrients for maximum crop production.

Soil Nutrient Retention and pH Buffering Capacity Are Enhanced by Calciprill and Sodium Silicate

“…Nevertheless, the inconsistent and slow effects of these organic amendments could be influenced by the recalcitrant property of charcoal, the raw materials used, and the handling methods. Besides, an unbalanced use of charcoal and sago bark ash can cause heavy metal toxicity, phosphorus fixation by calcium, soil salinization, and environmental pollution [27][28][29]. Therefore, amending soils with the right amount of inorganic liming materials which have relatively high neutralizing values and reactivity is essential.…”

Elevated Fe and Mn Concentrations in Groundwater in the Songnen Plain, Northeast China, and the Factors and Mechanisms Involved

“…The Fe and Mn concentrations were much higher in the groundwater samples with TP concentrations >0.4 mg/L than in the other samples (Figure 6). N and P pollution are mainly caused by agricultural activities [64,65], so N and P pollution may occur simultaneously. Excessive use of phosphate fertilizers occurs in the study area [66].…”

Dynamics of Phosphorus and Biostimulants on Agro-Morphology, Yield, and Essential Oil Profile of German Chamomile (Matricaria chamomilla L.) Under Acidic Soil Conditions of the Western Himalaya

“…In acidic soils, P becomes unavailable to plants as it gets fixed in the soil by sesquioxides, eventually leading to P deficiency. Thus, P becomes the most limiting nutrient in the crop production system (Johan et al, 2021 ). The reduced level of available P can adversely affect plant height, lateral plant spread, flower number, flower size, biomass, pollen production, etc.…”