Division of Soil Science and Agricultural Chemistry, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
Texas A&M AgriLife Research Center, Beaumnt, TX, 77713, USA.
Sci Rep. 2024 Apr 10;14(1):8420. doi: 10.1038/s41598-024-56618-w.
In recent years biochar (BC) has gained importance for its huge carbon (C) sequestration potential and positive effects on various soil functions. However, there is a paucity of information on the long-term impact of BC on the priming effect and nutrient availability in soil with different properties. This study investigates the effects of BC prepared from rice husk (RBC4, RBC6), sugarcane bagasse (SBC4, SBC6) and mustard stalk (MBC4, MBC6) at 400 and 600 °C on soil C priming and nitrogen (N), phosphorus (P), and potassium (K) availability in an Alfisol, Inceptisol, and Mollisol. BC properties were analyzed, and its decomposition in three soil orders was studied for 290 days in an incubation experiment. Post-incubation, available N, P, and K in soil were estimated. CO evolution from BC and soil alone was also studied to determine the direction of priming effect on native soil C. Increasing pyrolysis temperature enhanced pH and EC of most of the BC. The pyrolysis temperature did not show clear trend with respect to priming effect and nutrient availability across feedstock and soil type. MBC6 increased C mineralization in all the soil orders while RBC6 in Alfisol and SBC6 in both Inceptisol and Mollisol demonstrated high negative priming, making them potential amendments for preserving native soil C. Most of the BC showed negative priming of native SOC in long run (290 days) but all these BC enhanced the available N, P, and K in soil. SBC4 enhanced N availability in Alfisol and Inceptisol, RBC4 improved N and P availability in Mollisol and P in Alfisol and MBC6 increased K availability in all the soils. Thus, based on management goals, tailored BC or blending different BC can efficiently improve C sequestration and boost soil fertility.
近年来，生物炭（BC）因其巨大的碳（C）固存潜力和对各种土壤功能的积极影响而受到重视。然而，关于 BC 对不同性质土壤中激发效应和养分有效性的长期影响的信息很少。本研究调查了在 400 和 600°C 下由稻壳（RBC4、RBC6）、甘蔗渣（SBC4、SBC6）和芥菜秸秆（MBC4、MBC6）制备的 BC 对 Alfisol、Inceptisol 和 Mollisol 中土壤 C 激发和氮（N）、磷（P）和钾（K）有效性的影响。分析了 BC 的性质，并在一个培养实验中研究了其在三种土壤类型中的分解情况，历时 290 天。培养后，估计了土壤中有效 N、P 和 K 的含量。还研究了 BC 和土壤单独 CO 的释放，以确定对原生土壤 C 的激发效应的方向。提高热解温度会增强大多数 BC 的 pH 和 EC。热解温度与不同原料和土壤类型的激发效应和养分有效性之间没有明显的趋势。MBC6 增加了所有土壤类型的 C 矿化，而 RBC6 在 Alfisol 中，SBC6 在 Inceptisol 和 Mollisol 中均表现出高负激发，使它们成为保护原生土壤 C 的潜在改良剂。大多数 BC 在长期（290 天）内对原生 SOC 表现出负激发，但所有这些 BC 都提高了土壤中有效 N、P 和 K 的含量。SBC4 提高了 Alfisol 和 Inceptisol 中 N 的有效性，RBC4 提高了 Mollisol 中 N 和 P 的有效性，P 在 Alfisol 中提高了 MBC6 中 K 的有效性。因此，根据管理目标，定制 BC 或混合不同的 BC 可以有效地提高 C 固存并提高土壤肥力。
