Institute of Soil, Water and Environmental Sciences, Volcani Center, ARO, P.O. Box 15159, Rishon LeZion, 7528809, Israel; Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel.
Institute of Soil, Water and Environmental Sciences, Volcani Center, ARO, P.O. Box 15159, Rishon LeZion, 7528809, Israel.
J Environ Manage. 2022 Mar 1;305:114361. doi: 10.1016/j.jenvman.2021.114361. Epub 2021 Dec 25.
The impact of biosolid compost on the adsorption of orthophosphate (IP) to Mediterranean-type soils was studied. Eight soils were amended with a stable biosolid compost (ADSC) at 9:1 and 97:3 ratios (w/w). Four soils were amended with the dissolved organic matter (DOM) fraction of the ADSC at the amount added at the 9:1 mixture (810 mg C kg). Soils and their 9:1 soil‒ADSC mixtures were incubated for seven years. The maximum ADSC IP-adsorption capacity (S, Langmuir model) at native pH (≈7.5) was 850 mg P kg. Mixing the ADSC with the soils increased their S values by ca. 150 and 190 mg P kg in the 9:1 and 97:3 mixtures, which exceeded additivity by 50% and 575%. The addition of DOM similarly increased the S of three out of the four soils. Following the incubation, the soils' organic-C decreased by 34% and the ADSC-derived OC decreased by 60%. Still, the corresponding soil's and mixtures' average levels of labile IP either increased (by 60%) or remained steady (at ̴30% of total-P). Incubation increased the S of three soils and five soil‒ADSC mixtures and decreased their binding affinity (k), trends which were also reflected in the quantity/intensity parameters. This study showed that amending semi-arid Mediterranean soils with stable biosolids, and their long-term oxidative co-stabilization is conducive to increase their IP binding capacity and bioavailability. Finally, the often similar effects of the compost and its DOM on IP adsorption merits further research regarding the role of cation (Ca) bridging in IP‒DOM‒solid phase interactions.
研究了稳定生物固体堆肥（ADSC）对地中海型土壤中正磷酸盐（IP）吸附的影响。将 8 种土壤分别以 9:1 和 97:3（w/w）的比例与 ADSC 混合。将 ADSC 的溶解有机质（DOM）部分以添加到 9:1 混合物中的量（810 mg C kg）添加到 4 种土壤中。将土壤及其 9:1 土壤-ADSC 混合物在 7 年内进行培养。在自然 pH（约 7.5）下，ADSC 的最大 IP 吸附容量（Langmuir 模型）为 850 mg P kg。将 ADSC 与土壤混合可使 9:1 和 97:3 混合物中的 S 值分别增加约 150 和 190 mg P kg，这比加性增加了 50%和 575%。DOM 的添加同样增加了四种土壤中的三种土壤的 S 值。在孵育后，土壤的有机碳减少了 34%，ADSC 衍生的 OC 减少了 60%。然而，相应土壤和混合物中易解 IP 的平均水平要么增加（增加了 60%），要么保持稳定（约为总磷的 30%）。孵育增加了三种土壤和五种土壤-ADSC 混合物的 S 值，并降低了它们的结合亲和力（k），这些趋势也反映在数量/强度参数中。本研究表明，用稳定的生物固体和它们的长期氧化共稳定来改良半干旱地中海土壤有利于增加土壤对 IP 的结合能力和生物利用度。最后，堆肥及其 DOM 对 IP 吸附的影响往往相似，这值得进一步研究阳离子（Ca）桥接在 IP-DOM-固相相互作用中的作用。
