Background and aims

Soil organic phosphorus (P_org) is of interest for plant nutrition because it can comprise between 20 and 80% of total soil phosphate (P). This study aims to examine the effect of compost application on soil phosphatases and microbial biomass, which influence the P turnover and, furthermore, to examine the speciation of P_org.

Methods

Soil from a long-term field experiment (since 1997) which compares compost application with inorganic fertilization was analyzed for calcium-acetate-lactate extractable P (CAL-P), Olsen-P, acid (Acid-P_ase) and alkaline (Alk-P_ase) phosphatase activity and microbial biomass P. P_org speciation was additionally analyzed with liquid-state ³¹P nuclear magnetic resonance spectroscopy (³¹P-NMR).

Results

We found a significant increasing long-term effect of high compost application (equivalent to 400 kg ha⁻¹ N (400)) on Acid-P_ase (45%) and Alk-P_ase (58%). After compost application, Acid-P_ase increased by 41% in treatment 400 (3 days after compost application (DAA)). The ³¹P-NMR analysis showed a significant increase of inorganic orthophosphate (55%) after high compost application. Furthermore, the total phosphomonoester region was significantly decreased in the treatment 400 (8%).

Conclusions

We demonstrated that long-term compost application increases phosphatase activity which plays a key role in the mineralization of soil P_org. In particular, the decrease of the concentration of P_org species in the phosphomonoester region in the treatment 400 with high compost application highlights that an increased turnover affects this soil P pool and may provide P to plants. This knowledge provides a better understanding of how the P cycle responds to long-term compost fertilization.

中文翻译：

---

长期堆肥施用后磷酸盐周转指标的识别和量化——长期和单季影响

背景和目标

土壤有机磷 (P _org ) 对植物营养很重要，因为它占土壤总磷 (P) 的 20% 至 80%。本研究旨在研究堆肥应用对土壤磷酸酶和微生物生物量的影响，从而影响磷周转，并进一步研究 P _org的形态。

方法

长期田间实验（自 1997 年以来）对堆肥施用与无机肥料进行比较，对土壤进行了乙酸钙-乳酸可提取磷 (CAL-P)、奥尔森-P、酸性 (Acid-Pase ₎和碱性 (Alk)分析。 -P _ase）磷酸酶活性和微生物生物量 P.P _org形态还用液态³¹ P 核磁共振波谱（³¹ P-NMR）进行分析。

结果

^{我们发现大量堆肥施用（相当于 400 kg ha −1} N (400)）对酸磷酶₍ 45%) 和碱磷_酶(58%)的长期影响显着增加。应用堆肥后，处理 400 中的酸磷酶_增加了 41%（堆肥应用 (DAA) 后 3 天）。³¹ P-NMR分析显示，大量堆肥施用后，无机正磷酸盐显着增加（55%）。此外，处理400中总磷酸单酯区域显着减少（8%）。

结论

我们证明，长期堆肥施用会增加磷酸酶活性，这在土壤 P _org的矿化中起着关键作用。具体地，在具有高堆肥施用的处理400中磷酸单酯区域中P _org物种浓度的降低突出表明增加的周转影响该土壤P库并且可以向植物提供P。这些知识可以更好地理解磷循环如何响应长期堆肥施肥。