土壤改良剂和套种作物对幼龄橘园酸性土壤理化性质的影响

Effects of soil amendments combined with intercropping on physical and chemical properties of acid soil in young citrus orchards

为明确施用酸性土壤改良剂配合套种对幼龄橘园土壤理化性质及养分含量的影响,选取了生石灰、生石灰+火土灰为酸性土壤改良剂,绿豆和红薯为套种作物,以土壤清耕为对照,系统研究了不同酸性土壤改良剂和套种作物组合对土壤理化性质、全量和速效养分含量以及活性铝含量的影响。结果表明,较土壤清耕处理,各施用土壤改良剂配合套种处理均能显著降低土壤容重、增大土壤孔隙度、提高土壤饱和持水量和田间持水量,显著提高土壤pH值和有机质含量且降低活性铝含量(P<0.05),能不同程度提高土壤全量和速效养分。较施用生石灰处理,长期施用生石灰+火土灰累加效应明显,在改善土壤物理特性、提高土壤pH值和有机质含量、降低活性铝含量、提高土壤全钾、速效钾和有效磷含量等方面效果更好。套种绿豆和套种红薯在多数土壤理化特性指标上无显著差异,但套种红薯对提高土壤田间持水量、有机质含量方面效果更好,而套种绿豆则更有利于提升土壤全氮、全磷、碱解氮含量。总体来看,施用生石灰+火土灰配合套种红薯/绿豆均能有效改善橘园土壤理化性质。

In order to clarify the effects of acid soil amendments combined with intercropping on soil physical and chemical properties and nutrient content in young citrus orchards,quicklime and quicklime+fire soil ash were selected as acid soil amendments,mung bean and sweet potato were used as intercropping crops,and soil clean tillage was used as control.The effects of different acid soil amendments and intercropping crop combinations on soil physical and chemical properties,total and available nutrient contents and active aluminum content were systematically studied.The results showed that compared with the soil clean tillage treatment,the application of soil amendments combined with intercropping significantly reduced soil bulk density,increased soil porosity,soil saturated water holding capacity and field water holding capacity,significantly increased soil pH value and organic matter content and reduced active aluminum content(P<0.05),and increased soil total and available nutrients to varying degrees.Compared with the application of quicklime,the cumulative effect of long-term application of quicklime+fire soil ash was obvious,which was better in improving soil physical properties,increasing soil pH and organic matter content,reducing active aluminum content,and increasing soil total potassium,available potassium and available phosphorus content.There was no significant difference in most soil physical and chemical properties between intercropping mung bean and intercropping sweet potato,but intercropping sweet potato had better effect on improving soil field capacity and organic matter content,while intercropping mung bean was more conducive to improving soil total nitrogen,total phosphorus and alkali-hydrolyzable nitrogen content.In general,the application of quicklime+fire soil ash combined with interplanting sweet potato/mung bean could effectively improve the physical and chemical properties of citrus orchard soil.