Land‐use change from forest to agriculture in the volcanic ash‐derived soils of Mexico has increased over recent decades. It is likely that land uses and management practices, particularly fertilizer use have affected phosphorus (P) distribution and availability. The objective of this study was to evaluate the effects of land‐use types (native forest and maize mono‐cropping), and the related P addition, on the forms and distribution of soil P and their isotopic exchangeability. An Andisol, sampled from a cropping site, along with the contiguous area under native forest was treated with ³²P‐labelled potassium phosphate (KH₂³²PO₄). The soil samples were extracted after incubation times of 7, 21, 35 and 49 days. Phosphorus content and ³²P recovery in fractions sequentially extracted were assessed for each incubation time. Total soil P was dominated by inorganic fractions (79 to 86%) in both land‐use types. Resin‐Pi, bicarbonate extractable inorganic P (Bic‐Pi) and sodium hydroxide extractable inorganic P (NaOH_0.1‐Pi) were all raised with P addition. However, the proportion of organic P fraction was reduced under cropped soil. The recovery of ³²P in soils with P addition indicates that resin‐Pi, Bic‐Pi and NaOH_0.1‐Pi comprised nearly all the exchangeable P. In native soils with no P addition, more than 19% of the ³²P was recovered in Bic‐Po and NaOH_0.1‐Po forms. This finding indicates that organic P cycling is crucial when soil Pi reserves are presented in an inadequate amount. Ecologically based management has to be designed for replenishment and succeeding maintenance of soil organic P compounds to increase sustainable agricultural production.

中文翻译：

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墨西哥中部高地土地利用变化对磷组分和动力学的影响

近几十年来，墨西哥火山灰衍生土壤的土地利用从森林到农业的变化有所增加。土地使用和管理方式，尤其是肥料的使用，可能已经影响了磷的分布和可用性。这项研究的目的是评估土地利用类型（原生林和玉米单作）及其相关磷的添加对土壤磷的形态和分布及其同位素交换能力的影响。从种植地取样的安地索尔以及原生林下的邻近区域均用³² P标记的磷酸钾（KH ₂ ³² PO ₄）处理。在7、21、35和49天的孵育时间后提取土壤样品。磷含量和对于每个温育时间，评估按顺序提取的馏分中的³² P回收率。在两种土地利用类型中，土壤总磷均以无机组分为主（79％至86％）。树脂-Pi ，碳酸氢盐可萃取的无机P（Bic-Pi）和氢氧化钠可萃取的无机P（NaOH _0.1 -Pi）都通过添加P来提高。然而，在耕作土壤中有机磷组分的比例降低了。添加P的土壤中³² P的回收率表明，树脂-Pi ，Bic-Pi和NaOH _0.1 -Pi几乎包含所有可交换的P。在不添加P的天然土壤中，超过³²％的P被回收。 Bic-Po和NaOH _0.1‐Po表格。这一发现表明，当土壤中的磷储量不足时，有机磷循环至关重要。必须设计基于生态的管理，以补充和成功维护土壤有机磷化合物，以增加可持续农业生产。