有机肥替代部分化肥对椪柑生长、品质及土壤特性的影响

Effects of Partial Substitution of Chemical Fertilizer by Organic Fertilizer on Ponkan Growth and Quality as well as Soil Properties

【目的】通过有机肥替代等养分化肥对椪柑生长、产量、品质及土壤特性的影响研究,提出适宜的有机肥替代量,为柑橘化肥减量与提质增效技术提供理论依据。【方法】以15年生枳砧台湾椪柑为试验材料,设置不施肥(CK)、单施化肥(FP)、有机肥替代氮、磷、钾肥的比例分别为10%、25%、18%(T1)、有机肥替代氮、磷、钾肥的比例分别为15%、38%、27%(T2)、有机肥替代氮、磷、钾肥的比例分别为20%、51%、36%(T3)、有机肥替代氮、磷、钾肥的比例分别为30%、76%、54%(T4),共6个处理,除CK外,各施肥处理的氮、磷、钾养分一致,2019—2020年连续两年系统研究等养分有机肥替代化肥对椪柑当年生叶片、花、果等的干物质量积累、产量与品质、土壤理化性质、土壤碳排放与硝态氮淋失的影响。【结果】(1)两年试验施肥处理的椪柑春、秋梢叶片,花和果实的干物质量变化趋势类似,即随有机肥替代比的增加呈先升后降的趋势,且总体上T1和T2处理更有利于叶片、花和果干物质量的积累。2019和2020年各有机肥替代处理的产量分别较FP处理增加了7.2%—26.4%和2.0%—36.9%;(2)与FP相比,2020年各有机肥替代处理的可溶性固形物显著增长了7.4%—9.8%,其他品质指标也有提升,且以T2和T3处理的效果较好;(3)2020年各有机肥替代处理的土壤pH和有机质含量较FP分别显著提高了4.6%—12.6%和16.4%—25.1%;(4)与FP相比,有机含量替代处理的土壤碳排放通量平均提高了20.1%、土层硝态氮含量减少了13.9%,且随有机肥替代比的增加,硝态氮向深层土壤的迁移量越小;(5)通过主成分分析及对主要指标进行综合评分,各处理得分从高到低顺序为T3、T2、T4、T1、FP、CK。【结论】本试验条件下以T3处理效果最佳,兼顾树体生长发育、土壤良好理化特性和果实优质丰产,并能一定程度减轻土层硝态氮淋失的风险。

【Objective】Through systematical research focused on the effects of different organic fertilizer substitutions on growth,yield and quality,physicochemical properties of soil and orchard environment of ponkan under equal nutrient,it could be provided the suitable amount of organic fertilizer substitution for the scientific application of organic fertilizer and theoretical basis for enlarging high quality of citrus.【Method】The 15-year-old Taiwan ponkan grafted on Poncirus trifoliata(L.)was used as experimental materials.Six different treatments were performed,including no fertilization(CK),single chemical fertilizer(FP),substitution 10%of nitrogen(N),25%of phosphorus(P),18%of potassium(K)(T1),substitution 15%of N,38%of P,27%of K(T2),substitution 20%of N,51%of P,36%of K(T3),substitution 30%of N,76%of P,54%of K(T4).The nitrogen,phosphorus and potassium nutrient content of treatment except CK was consistent with research into the effects of different organic fertilizer substitution on the accumulation of citrus branches,leaves and fruits of dry matter in that year,fruit yield and quality,physicochemical properties of soil,carbon emissions and nitrogen leaching in 2019 and 2020.【Result】(1)The two-year’s research showed similar trends in growth indicators,such as spring and autumn leaf,fruit and flower of dry matter,with the growth of organic fertilizer substitution showing a trend of first rise and then decrease.On the whole,T1 and T2 treatment were beneficial to accumulate ponkan dry matters of leaf,fruit and flower.In 2019 and 2020,the yield of each organic fertilizer substitution treatment increased by 7.2%to 26.4%and 2.0%to 36.9%,respectively.(2)The soluble solids treated by organic fertilizer substitution treatment increased significantly by 7.4%to 9.8%compared with FP in 2020.Among other quality,T2 and T3 were better on the whole.(3)Each organic fertilizer substitution treatment of soil physicochemical properties promoted compared under FP in 2019 and 2020.The soil p H and organic matter treated by organic fertilizer will be significantly increased by 4.6%to 12.6%and 16.4%to 25.1%,respectively.(4)Compared with FP,each organic fertilizer substitution treatment of soil carbon flux was higher by 20.1%,while which of nitrous nitrogen was lower by 13.9%.With the increase of organic substitution ratio,the migration of nitrous nitrogen to deep soil was lower.(5)Through the analysis of the principal component and the comprehensive score of research index on ponkan’s growth,yield and quality,physicochemical properties of soil and environment,the score was sorted as T3>T2>T4>T1>FP>CK.【Conclusion】T3(organic fertilizer replacement 20%of N,51%of P,36%of K)was the best under this research,and this treatment was not only beneficial to the growth and development of citrus trees,but also conducive to the formation of good physical,chemical characteristics of the soil and fruit high-quality yield,to a certain extent,to reduce the risk of greenhouse gas emission and soil nitrogen leaching.