生物质炭和石灰对酸化紫色土的改良效果

Ameliorating Effects of Biochar and Lime on Acidified Purple Soil

为改良酸化紫色土,作者采用连续30 d的室内培养实验,研究了生物质炭和石灰单独和配合施用对紫色土酸度和肥力特征的改良效果。结果表明:单独或混合施用生物质炭和石灰均能提高紫色土的pH值,降低土壤的交换酸、交换性H^+和交换性Al^3+的含量,且随着改良剂用量的增加,对土壤酸度的改良效果越明显。由于生物质炭的物质组成丰富,富含碱性物质、盐基离子、磷素和有机质。施用生物质炭后能显著提高土壤中水溶性和交换性盐基离子、有机质和有效磷的含量。而单独施用石灰处理仅对土壤的交换性和水溶性Ca^2+含量有显著的提高效果,而对土壤其余盐基离子、有机质和有效磷含量影响不显著。由于生物质炭对土壤酸度有突出的改良效果,不同处理间的改良效果大小关系为:生物质炭和石灰配合施用>生物质炭单独施用>石灰单独施用,说明生物质炭与石灰配施或单独施用生物质炭是快速改良酸化紫色土的有效办法。

In order to study the ameliorative effects of biochar and lime on acidified purple soil,a 30 days incubation experiment was carried out and the acidity and fertility characteristics of acidified purple soil were analyzed.The results showed that the application of biochar and lime alone or in combination can increase the pH value of acidified purple soil and reduce the contents of exchangeable acidity,exchangeable H^+and exchangeable Al^3+.The amelioration increased with increasing usage of ameliorant.Biochar is rich in alkaline substances,base cations,phosphorus and organic matter.The application of biochar significantly increased the contents of water soluble and exchangeable base cations,organic matter and available phosphorus in the purple soil.However,the application of lime only increased the contents of soil water soluble and exchangeable Ca^2+significantly and almost had no effect on the content of other base cations,organic matter and available phosphorus in the soil.Taking the outstanding of biochar in the improvement of soil acidity into account,the ameliorative effect among different treatments in this study was followed this order:combined application of biochar and lime together>application of biochar alone>application of lime alone.Therefore,the application of biochar alone or combination with a small amount of lime is an effective way to rapidly ameliorate the acidification of purple soil.