The low efficiency of phosphorus fertilization in weathered soils can limit plant development. The application of biochars in these areas has been seen as an important way to increase the efficiency of phosphorus fertilization and to promote better plant growth. However, biochars are alkaline materials that can increase soil pH and thus change the nutrient dynamics, which has been often ignored in studies of this nature. Here, all treatments had their pH standardized at 6.1 to eliminate the influence of pH on biochar application responses. The main goal of this study was to evaluate the real potential of coffee straw and eucalyptus bark biochars, produced under different pyrolysis temperatures, in the optimization of phosphorus fertilization and the development of Brachiaria brizantha. A greenhouse experiment was set up in a 2 × 2 × 5 factorial scheme, conducted for 120 days. The biochars, prepared from coffee straw and eucalyptus bark at 350 and 600°C, were applied at five rates in a Red‐Yellow Oxisol. The application of biochars may reduce the demand for nutrients and correctives, optimize phosphorus fertilization and improve the development of Brachiaria brizantha, but this ability depends on the raw material and the pyrolysis temperature used in its production. All analysed biochars can contribute to higher tillering and dry matter production, but only coffee straw biochars and eucalyptus bark biochar produced at 350°C were efficient in the optimization of phosphorus fertilization until 120 days of cultivation of Brachiaria brizantha.

中文翻译：

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生物炭改性酸性土壤中磷的有效性和草生长：一项不包括土壤pH值影响的研究

风化土壤中磷肥的低效率会限制植物的发育。在这些地区使用生物炭已被视为提高磷肥效率和促进植物生长的重要途径。然而，生物炭是碱性物质，可以增加土壤的pH值，从而改变养分动态，在这种性质的研究中经常被忽略。在这里，所有处理的pH值均标准化为6.1，以消除pH值对生物炭施用响应的影响。这项研究的主要目的是评估在不同热解温度下生产的咖啡秸秆和桉树皮生物炭在优化施肥和发展Bracharia brizantha中的真实潜力。。温室实验以2×2×5阶乘方案进行，进行了120天。由咖啡秸秆和桉树皮分别在350和600°C下制备的生物炭以五种比率在红黄Oxisol中施用。生物炭的应用可以减少对养分和矫正剂的需求，优化磷肥并改善Brachiaria brizantha的发育，但是这种能力取决于原料及其生产中使用的热解温度。所有分析过的生物炭均可促进更高的分till和干物质生产，但只有在350°C下生产的咖啡秸秆生物炭和桉树皮生物炭才能最有效地优化磷肥，直到Brachiaria brizantha种植120天为止。