Phosphorus sorption, supply potential and availability in soils with contrasting parent material and soil chemical properties

Abstract

Soil phosphorus (P) management requires a more targeted and soil-specific approach than is currently applied for agronomic recommendations and environmental evaluation. Phosphorus buffering capacities control the supply of P in the soil solution and were measured across Irish soils with contrasting parent material and chemical properties. Langmuir sorption buffer capacities (MBCs) and binding energies (b) were strongly correlated with soil pH and extractable aluminium (Al). A broken-line regression fitted to the relationship between MBC and Al derived a change-point value for Al above which MBC increased linearly. Soils above the change point were predominantly acidic to neutral with non-calcareous parent material, with larger buffering capacities and binding energies than calcareous soils. Ratios of Mehlich3-Al and P (Al:P) were used to relate buffering capacity to supply potential in non-calcareous soils. Large ratios of Al:P were associated with poor P availability, characteristic of strongly P-fixing soils. Threshold values of iron-oxide paper strip P (FeO-P) and Morgan's P revealed Al:P ratios where soils began to supply P in available form. The change-point for Morgan's P fell within the current target index for P availability; however, the confidence interval was more compatible with previous agronomic P indices used in Ireland. Relationships between Morgan's P and measures of extractable P, M3-P and Olsen P, deviated in calcareous soils at large soil P contents, indicative of P precipitation processes dominating in these soils. Identifying differences in soil P buffering capacity at the laboratory scale would improve agronomic and environmental assessment at field and catchment scales.

Phosphorus Adsorption Capacity Evaluation for the Substrates Used in Constructed Wetland Systems: a Comparative Study

“…Overall, the maximum P sorption for all of the tested substrates increased as follows: quartz sands (III < II < I < IV) < activated carbon < zeolite < ceramic < furnace slag. The results of the present study demonstrated that the P adsorption capacities of substrates vary significantly; these findings are comparable with those reported in the literature [12,[24][25][26].…”

The Optimum Dose of Nitrogen, Phosporus, and Potassium to Improve Soybean (Glycine max (L) Merr) Productivity on Kayu Putih (Melaleuca cajuputi) Stands

“…Soil containing phosphates were usually alkaline, so it could not be absorbed by plants (Darmawijaya, 1990). This relationship was also confirmed from the research conducted by Daly et al (2015) who found a correlation between the content of Ca 2+ and P availability in the soil. A low content of K + and a high CEC soil was caused by the adsorption of heavy clay minerals type 2:1.…”

Relation between various soil phosphorus extraction methods and sorption parameters in calcareous soils with different texture

“…Phosphorus (P) is an important element for all life forms and is also an important nutrient for plant growth crop productivity (Daly et al, 2015;Stutter et al, 2012). Phosphorus application in agricultural soils may lead to accumulation of P (Delgado and Scalenghe, 2008;Sattari et al, 2012) as the approximate percent recovery of applied P for crops usually is between 10 and 25% (Wang et al, 2011).…”

“…In many countries, recommendations for P fertilizers are based on soil test methods and recently they were also used for environmental risk assessment Sharpley et al, 2003;Daly et al, 2015). It was indicated that the P extracted by extractants such as Olsen-P and Mehlich-3-P had correlated well with P loss via runoff and/or leaching (Wang et al, 2012).…”