Soil acidification is an important cause of declining crop yields in many countries, including Canada and the United States. Meanwhile, alkaline by‐products from forest resources are widely available but underused in agriculture despite their expected benefits on soil pH and fertility. The aim of this study was to determine the effects, throughout a 40‐wk laboratory incubation, of six different forest‐derived liming materials on soil pH and Mehlich‐3–extractable major nutrients in two acidic soils. Lime mud, two wood ashes (papermill biosolids and wood bark), two biochars (maple and pine), and a de‐inking paper sludge (DPS) were applied at calcium carbonate equivalence–based rates, according to the amount of lime required to achieve a target pH of 6.5 on each soil. A calcitic lime (CL) was used as a reference. All forest‐derived materials except pine biochar were equally effective as CL in increasing the pH of the two acidic soils after 40 wk of incubation. Lime mud quickly raised the pH after soil incorporation, and then the pH progressively declined. By contrast, DPS upon decomposition gradually increased soil pH over time. In terms of liming value based on dry mass of each material, lime mud was needed at the lowest amount (0.8 CL unit) to increase pH to the target value. Wood ash, particularly from wood combustion, was a significant direct source of P, K, and Mg, whereas maple biochar supplied large amounts of available K and Mg. This study demonstrated that forest‐derived alkaline by‐products can efficiently remediate soil acidity and improve soil fertility.

中文翻译：

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森林来源的石灰副产品：补救土壤酸度和增加土壤肥力的潜在好处

在许多国家，包括加拿大和美国，土壤酸化是导致农作物减产的重要原因。同时，来自森林资源的碱性副产物虽然在土壤pH和肥力方面具有预期的好处，但仍广泛用于农业，但并未得到充分利用。这项研究的目的是确定在40周的实验室培养过程中，六种不同的森林衍生的石灰材料对两种酸性土壤中pH和Mehlich-3可提取的主要养分的影响。石灰泥，两种木灰（造纸厂的生物固体和木皮），两种生物炭（枫木和松木）以及脱墨纸浆（DPS）以碳酸钙当量的比率施用，具体取决于所需的石灰量。在每种土壤上达到6.5的目标pH。钙石灰（CL）用作参考。温育40周后，除松木炭外，所有森林来源的材料均与CL一样有效，可提高两种酸性土壤的pH值。掺入土壤后，石灰泥会迅速提高pH值，然后pH逐渐下降。相比之下，分解后的DPS随时间逐渐增加土壤的pH值。就基于每种材料干质量的石灰值而言，需要以最低量（0.8 CL单位）使用石灰泥将pH值提高至目标值。木灰，特别是木材燃烧产生的灰烬是P，K和Mg的重要直接来源，而枫木生物炭提供了大量的可用K和Mg。这项研究表明，森林来源的碱性副产物可以有效地缓解土壤酸度并提高土壤肥力。