Fluid Fertilizers Improve Phosphorus Diffusion but not Lability in Andisols and Oxisols
Fluid Fertilizers Improve Phosphorus Diffusion but not Lability in Andisols and Oxisols
复制标题
液体肥料可改善磷的扩散，但不会改善安迪土和氧化土中的不稳定性
DOI：
10.2136/sssaj2013.02.0075
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发表时间：
2014
影响因子：
2.9
通讯作者：
M. Mclaughlin
中科院分区：
文献类型：
--
作者：
D. Montalvo;F. Degryse;M. Mclaughlin
与颗粒肥料相比，液体磷肥（P）由于减少了P沉淀而增加了石灰性土壤中P的有效性。目前还不清楚是否流态磷也可以提高酸性土壤中肥料磷的有效性。一个35天的培养实验评估的扩散，不稳定性和溶解度的P颗粒（磷酸钙和磷酸铵）和流体（磷酸铵和聚磷酸盐）肥料在两个Andisol和两个Oxisol。一个钙质Inceptisol和Alfisol进行了比较。磷的扩散和不稳定性进行了评估，使用一种新的可视化技术和同位素交换（24小时平衡），并在孵化结束时，残留的肥料颗粒进行了分析。在石灰性土壤中，除钙磷肥外，大部分磷（90%）从颗粒中扩散出来。在强P-吸附土壤（酸性和石灰性），P在流体形式的应用扩散进一步从应用点相比，颗粒P.然而，在Andisols和Oxisols，更大的扩散并没有导致更大的P不稳定性和溶解度;更多的P保持不稳定的颗粒（34%平均）比流体肥料（24%）。而在石灰性土壤中，施入液态磷可提高土壤中磷的不稳定性和溶解性。这些结果表明，在Andisols和Oxisols，强吸附，而不是沉淀反应限制肥料P的可用性，通过使用流体制剂在更大的土壤体积上散布肥料可能会降低P不稳定性。在这些土壤类型中，使用液体磷肥预计不会比颗粒状产品带来农学效益。
Fluid phosphorus (P) fertilizers increase availability of P in calcareous soils compared with granular fertilizers, because of reduced P precipitation. It is unclear whether fluid P forms may also enhance fertilizer P availability in acidic soils. A 35-d incubation experiment assessed the diffusion, lability, and solubility of P from granular (calcium phosphate and ammonium phosphate) and fluid (ammonium phosphate and polyphosphate) fertilizers in two Andisols and two Oxisols. A calcareous Inceptisol and an Alfisol were included for comparison. Phosphorus diffusion and lability was assessed using a novel visualization technique and isotopic exchange (24-h equilibration), and residual fertilizer granules were analyzed at the end of the incubation. Most P (90%) diffused out of the granules, except for calcium phosphate fertilizers in the calcareous soil. In the strongly P-sorbing soils (acidic and calcareous), P applied in fluid form diffused further from the application point compared with granular P. However, in the Andisols and Oxisols, the greater diffusion did not result in greater P lability and solubility; more P remained labile with the granular (34% on average) than with the fluid fertilizer (24%). In contrast, in the calcareous soil, the application of fluid P resulted in enhanced P lability and solubility. These results suggest that in Andisols and Oxisols, where strong adsorption rather than precipitation reactions limit fertilizer P availability, spreading the fertilizer over a larger soil volume by using fluid formulations may reduce P lability. No agronomic benefit over granular products is expected from the use of fluid P fertilizers in these soil types.