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开发可靠的预测模型的挑战:在土壤氧化还原变化下不可预测的释放

Filippo Saiano¹, Riccardo Scalenghe¹

¹Dipartimento Scienze Agrarie, Alimentari e Forestali, Università degli studi di Palermo, Italy.

|December 11, 2024

概括

洪水改变了土壤 (P) 动态,减少了无氧下P的释放. 土壤类型在减少条件下显著影响P吸附能力,但通用预测模型仍然难以捉摸.

科学领域:

土壤科学土壤科学
环境化学环境化学
农业科学农业科学

背景情况:

(P) 对植物营养至关重要,但其不均的分布需要使用肥料.
过度使用肥可以导致有害的水污染.
了解土壤的动态,尤其是在洪水等不断变化的环境条件下,至关重要.

研究的目的:

为了调查 (P) 从土壤P-吸附复合物中释放的 (P) 在洪水诱导的减少 (无氧) 下.
量化不同类型的土壤和降低条件对P吸附能力的影响.
根据土壤特性评估预测P释放的潜力.

主要方法:

使用吸附/脱附等热器直接测量12种不同土壤中的P-吸附复合物.
在交替减少条件 (ARC) 和连续减少条件 (CRC) 下比较P吸附.
分析了土壤特性,以确定与P吸附和释放的相关性.

主要成果:

无氧降低了平衡溶液中的P度,表明P脱吸减少.
石灰质土壤在ARC下显示出较高的最大P吸附率 (Xmax),而不是CRC.
酸性,有机物质丰富的土壤在ARC下表现出最高的Xmax (123 mmol P kg-1).
酸性,轻质地质的土壤在CRC下显示出更高的平均Xmax.

结论:

无氧下土壤P释放是复杂的,并且随着土壤类型和氧化还原条件而有很大变化.
现有的土壤属性和气候数据不足以开发土壤P溶解的预测模型.
无氧诱导的P释放缺乏可预测的模式,凸显了管理P损失的挑战.

关键词:

最大的吸附能力.一个零点的零点.过度肥沃的土壤过度肥沃的土壤

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