暗排技术对设施连作土壤改良及切花菊品质的影响

Effect of Subsurface Pipe Drainage System on Greenhouse Soil Improvement and Cut Chrysanthemum Quality in Continuous Cropping System

针对温室、大棚等设施栽培条件下的土壤随着连作年限的增加,土壤理化性状变劣、养分比例失调、土壤次生盐渍化加重、生产性能降低这一现象,采用暗管排水排盐技术,在稻草还田(800 kg/hm^2)配套措施条件下,研究了暗管不同埋管间距(2、4、6 m)对设施连作表层土(0~15 cm)有机质、速效养分(碱解氮、有效磷和速效钾)、盐分含量以及切花菊‘神马’品质的影响。结果表明:暗排技术能明显增强切花菊的根系活力,对切花菊主要品质(株高、茎粗、花径、舌状花数及生物量)的提高具有积极作用,其中4 m的埋管间距处理效果最佳;对土壤有机质和速效养分含量的提高效果埋管间距4 m处理显著高于埋管间距2 m和6 m处理;暗排技术对于土壤的降渍排盐作用明显,可显著降低表层土壤的含水量、电导率、全盐量以及主要盐分离子含量(Ca^2+和SO4^2–),并且随着埋管间距的减小,降渍排盐的效果越明显。综合比较分析各相关试验结果,结合暗管埋设初期成本投入的考虑,4 m的埋管间距处理能最有效地改良设施连作土壤及提高切花菊的品质。

With the increase of continuous cropping years,the physical and chemical properties of greenhouse soil is deteriorating,the proportion of nutrients is out of balance gradually,the secondary stalinization of soil is increasing,and the production performance is reducing more and more seriously.In this study,under the condition of straw returning to field at 800 kg/hm2,the subsurface pipe drainage system was used to investigate the effects of different pipe spacing(2,4 and 6 m)on organic matter content,available nutrients(available nitrogen,available phosphorus and available potassium)and salt content in surface soil(0–15cm)as well as the quality of cut chrysanthemum‘Jimba’.The results showed that the subsurface pipe drainage system significantly enhanced the root activity of cut chrysanthemum and had a positive improvement in the quality of cut chrysanthemum(plant height,stem diameter,flower diameter,ray floret number and shoot dry weight).Among the treatments evaluated,4 m pipe spacing treatment improved soil organic matter and available nutrient contents more significantly compared with 2 m and 6 m pipe spacing treatments.4 m pipe spacing not only had positive effects on groundwater depth controlling and desalination,but also had significant effect on reducing water content,electrical conductivity,total salt content and the main salt ions contents(Ca^2+and SO4^2–)in the surface soil.With the decrease of buried pipe spacing,the effects of groundwater depth controlling and desalination became more obvious.Combined with the initial cost of embedded buried pipe into account,the treatment of 4 m pipe spacing is regarded as the most economical way to improve both soil and cut chrysanthemum qualities in continuous cropping greenhouse.