In recent times, there has been increased focus on a holistic approach to soil remediation with consideration of social, economic and environmental factors. Consequently, there is a demand from practitioners and regulators alike for suitable ways to measure ancillary outcomes, for example, effects on soil quality. Here we show that biochar, when applied to land to remediate lead (Pb)-contaminated soils, can lead to environmental improvements not realized by adding mined or manufactured phosphates. Here, we study a Pb-contaminated soil amended with two phosphate fertilizers (slow- and fast-release) and with biochars produced from poultry litter and from biosolids at three temperatures (300 °C, 400 °C and 500 °C). The results show that, unlike the fast-release P fertilizer, biochars did not result in an increase in the amount of leachable P that could be released into the environment. Biochars prepared at 500 °C presented a higher value of the integrative geometric mean of soil enzyme activity, compared to the P fertilizers. Overall, our research shows that biochars, particularly those prepared at the higher temperature tested, are a suitable alternative to P fertilizers as an integrative remediation strategy in Pb-contaminated soils, enabling soil biological restoration.

中文翻译：

---

使用富含磷的生物炭修复铅污染的土壤：对土壤酶和可提取磷的影响

近年来，考虑到社会，经济和环境因素，人们越来越注重采用整体方法进行土壤修复。因此，从业者和管理者都要求有合适的方法来测量辅助结果，例如对土壤质量的影响。在这里，我们表明，将生物炭应用于土地以修复被铅（Pb）污染的土壤时，可导致环境改善，这是通过添加开采或制造的磷酸盐无法实现的。在这里，我们研究了在三种温度（300°C，400°C和500°C）下用两种磷酸盐肥料（缓释和快释）以及家禽垫料和生物固体产生的生物炭改良的受Pb污染的土壤。结果表明，与速释磷肥不同，生物炭并不会增加可释放到环境中的可浸出磷的量。与磷肥相比，在500°C下制备的生物炭具有更高的土壤酶活性综合几何平均值。总体而言，我们的研究表明，生物炭，尤其是在较高温度下测试的生物炭，是磷肥的综合补救策略，是磷肥的合适替代品，可实现土壤生物恢复。