Prescribed fire (slash and burn) tends to impede the sustainable functionality of soil in agricultural systems. However, the use of amendment has a potential to reverse these negative effects. Prescribed fire is still used by farmers in Nigeria for land preparation before planting. This has continued to increase soil degradation in Nigeria with no agronomic activities that could ameliorate this effect in view. This study therefore examined the influence of prescribed fire and grass mulch on selected soil physical properties and organic carbon immediately after burning, and the potential of amendment to improve the soil properties negatively affected by fire. The prescribed fire treatments consisted of 200 °C and 500 °C fire intensities using (a large perennial bunch of grass that is dominant in the study area) as the fuel and also served as the grass mulch. Cured poultry manure at 7.5 t ha was combined with urea at 40 kg N ha and applied as a combined amendment while a single dose of urea was applied at 80 kg N ha as an inorganic amendment. The experiment was carried out across three cropping seasons on maize ( L.) in 2019 and 2020. Soil water repellency (), bulk density (D), soil unsaturated hydraulic conductivity (), water stable aggregates (WSA), soil strength (SS), and soil organic carbon (SOC) were determined immediately after burning and three months after amendments were applied. Data obtained were subjected to analysis of variance and means separated using the Duncan multiple range test at p≤0.05. Results showed that prescribed fires increased by an average of 50.1 and 62.7 % for 200 °C and 500 °C intensities, respectively compared with the control. Three months later, the was reduced by 25.9 % and 62.3 % for 200 °C and 500 °C, respectively when no amendment was added. Notably, the addition of sole urea and cured poultry manure + urea reduced the by 50 % and 48.5 %, respectively in the 200 °C intensity, and 62.2 % and 62.7 % in the 500 °C intensity, respectively. Also, was reduced by an average of 49.6 and 62.2 % by 200 °C and 500 °C intensities, respectively just after burning. However, it was not improved three months after the prescribed fires despite the applied amendments. The prescribed fire of 200 °C and grass mulch had no significant influence on OC just after the fire. Also, amendments did not significantly improve OC three months after prescribed fire. Therefore, the non-improvement of other soil properties, after the applied amendments, showed that further study is required to determine the required rate of the applied amendments that will significantly improve other soil properties negatively affected by prescribed fire in agricultural soils.

中文翻译：

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尼日利亚伊费岛农田中规定的火和草覆盖物对选定土壤特性的影响以及改良潜力


规定的火灾（刀耕火种）往往会阻碍农业系统中土壤的可持续功能。然而，使用修正案有可能扭转这些负面影响。尼日利亚农民在种植前仍然使用规定的火来整地。这继续加剧了尼日利亚的土壤退化，而没有任何农艺活动可以改善这种影响。因此，本研究研究了规定的火和草覆盖物对燃烧后立即选定的土壤物理特性和有机碳的影响，以及改善受火负面影响的土壤特性的潜力。规定的火灾处理包括 200°C 和 500°C 的火灾强度，使用（研究区域占主导地位的一大堆多年生草）作为燃料，也用作草覆盖物。将 7.5 t ha 的固化家禽粪便与 40 kg N ha 的尿素混合并作为组合改良剂施用，而单剂量尿素以 80 kg N ha 的量作为无机改良剂施用。试验在2019年和2020年三个种植季节的玉米（L.）上进行。土壤拒水性（）、容重（D）、土壤不饱和导水率（）、水稳定性团聚体（WSA）、土壤强度（SS） ）和土壤有机碳（SOC）在燃烧后立即测定，并在施用修正后三个月测定。使用 Duncan 多重范围检验在 p≤0.05 下对获得的数据进行方差分析和均值分离。结果显示，与对照相比，在 200 °C 和 500 °C 强度下，规定的火灾平均分别增加了 50.1 % 和 62.7 %。三个月后，下降了25.9%和62。当未添加修正时，200 °C 和 500 °C 分别为 3 %。值得注意的是，添加单一尿素和腌制家禽粪便+尿素在200℃下的强度分别降低了50%和48.5%，在500℃下的强度分别降低了62.2%和62.7%。此外，燃烧后在 200 °C 和 500 °C 强度下，平均分别减少 49.6% 和 62.2%。然而，尽管进行了修订，但在规定的火灾发生三个月后，情况并没有得到改善。规定的200℃火烧和草覆盖对火烧后的OC没有显着影响。此外，修正案并没有显着改善规定开火后三个月的 OC。因此，在应用修正后，其他土壤特性没有得到改善，这表明需要进一步研究以确定应用修正所需的比率，以显着改善农业土壤中受规定火灾负面影响的其他土壤特性。