Pyrolysis temperature is known to affect the potential of biochar as a nutrient-holding soil amendment, but the mechanism is unclear. In this study, physiochemical properties of biochar derived from switchgrass, water oak and biosolid at different pyrolysis temperatures were characterized using multiple techniques. In addition, biochar sorption of nitrogen nutrients in forms of ammonium (NH₄⁺), nitrite (NO₂⁻) and nitrate (NO₃⁻) was investigated. The results indicated that the profound effects of pyrolysis temperature on biochar physiochemical properties were feedstock-specific. Similarly, biochar derived from different feedstocks at different temperatures exhibited different strengths to retain NH₄⁺, NO₂⁻ and NO₃⁻. The maximum NH₄⁺ retention capacities were found with the biochar of switchgrass produced at 800 °C (10.47 mg g⁻¹), biochar of water oak at 400 °C (3.82 mg g⁻¹), and raw biosolids (43.29 mg g⁻¹). Meanwhile, biochar was found to have limited (switchgrass and water oak) and negative (biosolids) retention for NO₂⁻ and NO₃⁻. The cation exchange capacity (CEC) and morphological characteristics (e.g., porosity) were found to be the predominant factors affecting biochar NH₄⁺ sorption.

已知热解温度会影响生物炭作为养分土壤改良剂的潜力，但机理尚不清楚。在这项研究中，使用多种技术表征了柳枝,、水栎和生物固体在不同热解温度下的生物炭的理化特性。另外，在铵的形式的氮养分的生物炭吸附（NH ₄ ⁺），亚硝酸根（NO ₂ ^- ）和硝酸（NO ₃ ^- ）进行了研究。结果表明，热解温度对生物炭理化性质的深远影响是原料特异性的。同样，在不同温度下衍生自不同原料的生物炭表现出不同的保留NH _4的强度。⁺，NO ₂ ^-和NO ₃ ^- 。在800°C（10.47 mg g ^-1）生产的柳枝the生物炭，400°C（3.82 mg g ^-1）的水栎生物炭和原始生物固体（43.29 mg g）中发现了最大的NH ₄ ⁺保留能力。^-1）。同时，发现生物炭具有有限的（柳枝稷和水栎）和负极（生物固体）保持为NO ₂ ^-和NO ₃ ^- 。发现阳离子交换容量（CEC）和形态特征（例如，孔隙率）是影响生物炭NH ₄ ⁺吸附的主要因素。