Acid whey deriving from milk processing is a nutrient-rich organic residue, with high potential for use in agriculture. However, in order to establish adequate application doses, it is paramount to understand its mineralization dynamics in the soil. The aims of this study were to evaluate C and N mineralization in two soils fertilized with acid whey and compare the efficiency of distinct incubation methods with and without leaching techniques in predicting the potentially mineralizable N of this residue. Samples of two soils (Haplustox and Haplustult) were submitted to five acid whey doses (0, 80, 160, 240, and 320 kg N ha⁻¹), and the mineralization of C and N was determined. A pot experiment was conducted with the same soils and doses, in order to determine growth and N absorption by maize. C mineralization increased in both speed and quantity with the application of acid whey. Similarly, the potentially mineralizable N was increased, displaying mean values of 79.7 and 68.2 mg N kg⁻¹ in the methods with and without leaching, respectively. N mineralization had strong correlation with absorbed N (r = 0.97 and 0.96, in the methods with and without leaching, respectively). The correlation between net mineralized N and absorbed N was higher without leaching (r = 0.98), in comparison to the leaching method (r = 0.89). Acid whey causes net N immobilization at the beginning of incubation, resulting in low N availability during this period, and its mineralization was better evaluated by the method without leaching.

来自牛奶加工的酸乳清是一种营养丰富的有机残留物，具有很大的农业应用潜力。但是，为了确定适当的施用剂量，了解其在土壤中的矿化动力学至关重要。这项研究的目的是评估在两种用酸乳清施肥的土壤中的碳和氮矿化作用，并比较采用和不采用浸出技术的不同孵化方法预测该残留物潜在矿化氮的效率。对两种土壤（Haplustox和Haplustult）的样品进行了五次酸乳清剂量处理（0、80、160、240和320 kg N ha ^-1），并确定了C和N的矿化作用。在相同的土壤和剂量下进行盆栽试验，以确定玉米的生长和氮吸收。随着酸乳清的应用，碳矿化的速度和数量都增加了。类似地，潜在的可矿化氮增加，在有和没有浸出的方法中分别显示出79.7和68.2 mg N kg ^-1的平均值。氮的矿化作用与吸收的氮有很强的相关性（ 在有和没有浸出的方法中，r分别为0.97和0.96）。净之间的相关性矿化氮和吸收n为高于无浸出（[R  = 0.98），相比于浸出方法（ř = 0.89）。酸乳清在培养开始时会导致净氮固定化，导致此期间氮的利用率较低，并且通过该方法可以更好地评估其矿化程度，而不会发生浸出。