Department of Soil Science, Lasbela University of Agriculture, Water and Marine Sciences, Lasbela, Uthal Balochistan, Pakistan.
Federal University of Santa Maria, 1000 Roraima Ave, Santa Maria, RS, 97105-900, Brazil.
Sci Rep. 2024 Mar 1;14(1):5126. doi: 10.1038/s41598-024-55430-w.
The utilization of biochar's as soil amendments for enhancing nutrient retention in subsoils present potential limitations. To address this issue, we conducted a greenhouse experiment to assess the effects of various biochar's derived from animal manures (swine manure, poultry litter, cattle manure) and plant residues (rice straw, soybean straw, corn straw) when applied to surface of an acidic soil. Our study focused on wheat crops under a no-tillage system, with a subsequent evaluation of the residual impacts on soybeans. The experimental design involved the application of biochar's at different rates i.e. 10 and 20 Mg ha, followed by the assessment of their influence on NPK levels, pH, and exchangeable Al in stratified soil layers (0-5, 5-10, 10-15, and 15-25 cm). Furthermore, we investigated the interplay between biochar doses and the application of nitrogen (N) in the top 5 cm of soil, specifically examining , , P and K levels. Our findings revealed that in the top 5 cm of soil, biochar doses and N application significantly affected , , P and K concentrations. However, in deeper soil layers, no significant differences were observed among biochar doses with or without N application. Interestingly, K levels were impacted throughout all soil depths, regardless of the presence or absence of N application. Moreover, biochar application up to a 5 cm depth induced favorable changes in soil pH and reduced exchangeable Al. In contrast, deeper layers experienced a decrease in soil pH and an increase in exchangeable Al following biochar treatment. In conclusion, our study demonstrates that biochar's can effectively retain NPK nutrients, enhance soil pH, and decrease exchangeable Al, independent of the type and dosage of application under a no-tillage system. Nonetheless, the efficacy of biochar amendments may vary with soil depth and type of nutrient, warranting careful consideration for maximizing their benefits in sustainable agricultural practices.
生物炭作为土壤改良剂，用于增强底土中的养分保留，存在潜在的局限性。为了解决这个问题，我们进行了一项温室实验，评估了不同的生物炭（来自动物粪便（猪粪、家禽粪便、牛粪）和植物残渣（稻草、大豆秸秆、玉米秸秆））施用于酸性土壤表面时的效果。我们的研究集中在免耕系统下的小麦作物上，随后评估了对大豆的残留影响。实验设计包括以不同的速率（即 10 和 20 Mg ha）应用生物炭，然后评估它们对分层土壤层（0-5、5-10、10-15 和 15-25 cm）中 NPK 水平、pH 值和可交换 Al 的影响。此外，我们研究了生物炭剂量与氮（N）在表层 5 cm 土壤中的应用之间的相互作用，特别考察了 、 、P 和 K 水平。我们的研究结果表明，在表层 5 cm 的土壤中，生物炭剂量和 N 应用显著影响 、 、P 和 K 浓度。然而，在较深的土壤层中，无论是否应用 N，生物炭剂量之间没有观察到显著差异。有趣的是，K 水平在所有土壤深度都受到影响，无论是否应用 N。此外，将生物炭应用于 5 cm 深的土壤会引起土壤 pH 值的有利变化，并降低可交换的 Al。相比之下，在生物炭处理后，较深的土层土壤 pH 值降低，可交换的 Al 增加。总的来说，我们的研究表明，生物炭可以有效地保留 NPK 养分，提高土壤 pH 值，降低可交换的 Al，这与免耕系统下的生物炭类型和剂量无关。然而，生物炭改良剂的功效可能因土壤深度和养分类型而异，因此需要仔细考虑以最大限度地提高其在可持续农业实践中的效益。
