Civil & Environmental Engineering, University of Washington, Seattle, WA 98105, USA.
Environ Pollut. 2013 Nov;182:37-44. doi: 10.1016/j.envpol.2013.06.024. Epub 2013 Jul 25.
Several studies have shown Soluble Reactive Phosphorus (SRP) analyses provide a poor index of dissolved phosphorus (P) bioavailability in natural systems. We tested 21 inorganic and organic P containing compounds with series of nutrient uptake and bioavailability bioassay experiments and chemical characterizations. Our results show that in 81% of cases, these compounds did not fit the classic assumption that SRP approximately equals Bioavailable P (BAP). Many organic compounds were classified as non-reactive, but had very rapid uptake kinetics and were nearly entirely bioavailable (e.g., several nucleic acids, ATP, RNA, DNA and phosphatidylcholine). Several inorganic compounds also classified as non-reactive but had high bioavailability (i.e., sodium tripolyphosphate and phosphorus pentoxide). Conversely, apatite was operationally classified as reactive, but had low bioavailability. Due to their tendency to alias as SRP, but recalcitrance and very low bioavailability, humic-(Al/Fe)-phosphorus complexes may play an especially important role in the dissolved phosphorus dynamics of natural systems.
多项研究表明，可溶性反应磷（SRP）分析不能很好地反映自然系统中溶解态磷（P）的生物可利用性。我们通过一系列营养吸收和生物有效性生物测定实验以及化学特性测试，对 21 种含有无机和有机 P 的化合物进行了测试。结果表明，在 81%的情况下，这些化合物不符合 SRP 约等于生物可利用磷（BAP）的经典假设。许多有机化合物被归类为非反应性的，但具有非常快速的吸收动力学，几乎完全是生物可利用的（例如，几种核酸、ATP、RNA、DNA 和磷脂酰胆碱）。一些无机化合物也被归类为非反应性的，但具有高生物利用度（例如，三聚磷酸钠和五氧化二磷）。相反，磷灰石在操作上被归类为反应性的，但生物利用度低。由于它们容易与 SRP 混淆，但难以降解且生物利用度极低，腐殖质（Al/Fe）-磷复合物可能在自然系统的溶解态磷动态中发挥特别重要的作用。
