Demand for phosphorus (P) resources other than non-renewable P rock has driven the development of several P recovery technologies from municipal wastewater treatment and directed recovery of P into valuable fertilizers (struvite, ash, iron phosphate, etc.). Although the bioavailability of novel secondary P fertilizers has been examined in previous studies, insufficient attention has been paid to defining optimal plant growth duration and monitoring conditions to assess the dynamic changes in P. Accordingly, five fertilizers recovered from municipal wastewater: two struvites (STRSL and STRLQ), two ashes (ASH1 and ASH2), and iron-phosphate pelletized sludge (FeP) using triple superphosphate (TSP) as a positive control and blank (zero P) as a negative control, were applied to P poor-sand at three P doses (equivalent to 30, 60, and 90 kg P₂O₅ ha⁻¹). Fertilizer impact on perennial ryegrass (Lolium perenne) dry matter (DM) and P concentration were evaluated on a monthly basis for seven months. DM and relative agronomical efficiency (RAE) have shown the same trend between the fertilizers, but only at the lowest P dose (corresponding to 30 kg P₂O₅ ha⁻¹). At higher P doses (60, and 90 kg P₂O₅ ha⁻¹) the differences in DM and RAE among the fertilizers diminished. STRLQ, STRSL, ASH1 and FeP expressed a rather steady P release pattern, while ASH2 had a delay of four cuts and increase afterward. Monitoring the P uptake during four months of perennial ryegrass growth turned out to be the minimum, and seven months the optimum period for reaching the full capacity of the slow-release P fertilizers.

除了不可再生的 P 岩石之外，对磷 (P) 资源的需求推动了多种 P 回收技术的发展，这些技术从市政废水处理和直接将 P 回收为有价值的肥料（鸟粪石、灰分、磷酸铁等）。尽管在以前的研究中已经检查了新型二次磷肥的生物利用度，但没有充分注意确定最佳植物生长持续时间和监测条件以评估磷的动态变化。 因此，从城市废水中回收的五种肥料：两种鸟粪石（STRSL）和 STRLQ）、两种灰分（ASH1 和 ASH2）以及使用三重过磷酸钙 (TSP) 作为阳性对照和空白（零 P）作为阴性对照的磷酸铁颗粒污泥 (FeP)，在三个 P 剂量（相当于 30、60 和 90 kg P₂ O ₅公顷^-1 )。肥料对多年生黑麦草 ( Lolium perenne ) 干物质 (DM) 和 P 浓度的影响在七个月内按月评估。DM 和相对农艺效率 (RAE) 在肥料之间显示出相同的趋势，但仅在最低 P 剂量下（对应于 30 kg P ₂ O ₅ ha ^-1）。在较高的 P 剂量（60 和 90 kg P ₂ O ₅ ha ^-1) 肥料之间 DM 和 RAE 的差异减小。STRLQ、STRSL、ASH1 和 FeP 表达了相当稳定的 P 释放模式，而 ASH2 延迟了四次削减并随后增加。多年生黑麦草生长 4 个月期间对磷吸收的监测结果证明是最低的，而 7 个月是达到缓释磷肥全部容量的最佳时期。