Changes in Soil Phosphorus Pools and Chemical Properties under Liming in Nitisols

What is it about?

Understanding the nutrient dynamics in acid soil is fundamental to carry out proper management. *e study was conducted toinvestigate phosphorus (P) pools and selected properties under different rates of lime for acid nitisols of Farawocha, SouthernEthiopia. Four lime rates incubated for a month in three replications were tested. *e lime rates were 0 t/ha (0%), 5.25 t/ha (50%),10.5 t/ha (100%), and 15.75 t/ha (150%). Lime requirement (LR) for 100% was calculated targeting soil pH of 6.5. Data on the Ppools such as soluble P (P-sol) and bounded forms of P with iron (Fe-P), aluminum (Al-P), calcium (Ca-P), organic part (Org-P),residual P (Res-P), and total of P fractions were measured. In addition, changes in soil chemical properties such as pH, ex-changeable acidity, calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), copper (Cu), boron (B), zinc (Zn), and manganese (Mn)were analyzed. *e result showed that total P was 357.5 mg/kg. Compared to nontreated soil, liming at a rate of 15.75 t/hasignificantly improved P-sol (34.2%,r2�0.88), Ca-P (61.6%,r2�0.92), and Res-P (195%,r2�0.94); however, it reduced Fe-P(58.5%,r2� −0.83), Al-P (71%,r2� −0.97), and Org-P (19.1%,r2�0.93). Overall, the P-associated fractions in the soil, regardless ofthe lime rates, were in the order of Org_P>Res_P>Fe_P>Ca_P>Al_P>P-sol. Liming raised soil pH by 2.1 units (4.5 to 6.6)over nonlimed soil, whereas it reduced exchangeable acidity from 4.18 to 0.23 meq/100 g soil. Available P, Ca, Mg, S, Cu, Zn, and Bcontents were significantly improved with lime application. However, liming reduced Fe and Mn contents. In conclusion, thesefindings showed that liming facilitated the release of P from various pools, modified pH and exchangeable acidity, and resulted inbeneficial changes for most of the soil chemical properties .

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Photo by Devi Puspita Amartha Yahya on Unsplash

Photo by Devi Puspita Amartha Yahya on Unsplash

Why is it important?

This work helps to understand the soil P.

Perspectives