施用枝条堆肥对梨果和土壤质量影响效应的综合评价

Comprehensive assessment of effects on fruit and soil quality of application of branch compost in a pear orchard

【目的】探明枝条堆肥和有机肥施用对密植梨园梨果产量、品质和土壤理化性状的效应。【方法】采用枝条堆肥(BCT)、枝条堆肥+生物有机肥(MT)、羊粪(ST)和化肥(CT)4种施肥处理,结合主成分分析对果实品质和土壤质量进行综合评价。【结果】枝条堆肥+生物有机肥MT处理显著提高了果实单株产量,较化肥处理增产19.78%;有机肥连续施用后可改善果实的品质,与化肥处理相比,ST和MT处理提高了果实可溶性固形物和维生素C含量,MT处理还增加了果实可溶性糖含量,ST和BCT处理后增强了果实硬度,提高了有机酸含量。不同施肥处理对土壤理化性状有显著的影响,ST处理土壤pH有所提高,MT连续处理后0~20 cm和20~40 cm土层的pH明显低于CT;羊粪和枝条堆肥+生物有机肥均有效提高了0~20 cm和20~40 cm土层土壤有机质和碱解氮含量,并且MT处理促进了土壤铁元素有效性的提升。通过主成分分析法进行综合评价,不同施肥处理对果实品质和土壤质量的影响综合得分排序为MT>ST>BCT>CT,MT处理综合得分为0.6758,排名第1位。【结论】施用有机肥处理对果实品质和土壤质量的提升作用均优于纯化肥处理,尤其在MT处理下表现出了最佳的施肥效果。

【Objective】Collection and utilization of agricultural waste is a difficult in China.Pruned branches from fruit trees are a special kind of agricultural waste,which is rich in organic matters and mineral nutrients.However,due to its hard texture and complex structure,it is difficult to be reutilized,and is carelessly discarded or burned in large quantities causing great environmental pollution and safety hazards.Aerobic composting is an effective method to transform biological wastes into valuable organic fertilizer,which can be applied to the field,bringing both economic and ecological benefits.There is still a lack of systematic and comprehensive reports on the application of compost from fruit tree branches to the field,especially on the changes in fruit and soil quality and tree productivity after application.Therefore,it is necessary to investigate the effects of application of branch compost and organic fertilizer on fruit yield and quality and soil physical and chemical properties in densely-planted pear orchards.【Methods】Four fertilization treatments including branch compost(BCT),branch compost combined with bio-organic fertilizer(MT),sheep manure(ST)and chemical fertilizer(CT)were set up,and the yield and quality of fruit,and the physical and chemical properties of soils at depths of 0-20,20-40 and 40-60 cm were investigated,and comprehensively evaluated with the principal component analysis.The amount of sheep manure in ST in the test site was taken as the standard,and the organic matter in BCT and MT treatments was equal to that in ST,and the amounts of N2O,P2O5 and K2O in all treatments were equal.【Results】The results showed that MT significantly increased yield,which was 19.78 percent higher than that of CT.BCT and ST significantly increased fruit firmness after continuous application for two years.Continuous application of organic fertilizer improved fruit quality significantly.Compared with CT,ST and MT increased the contents of soluble solids and vitamin C in fruit.MT also increased the content of soluble sugars,and ST and BCT enhanced fruit firmness and increased the content of organic acids.There was significant difference in fruit and soil quality in different treatments.Soil pH was increased by sheep manure application,and decreased by continuous treatment of MT in 0-20 and 20-40 cm soil layers.The total salt content in 0-20 cm soil layer significantly increased in MT,and was the lowest in ST,and that in MT was significantly lower than in the other treatments in 20-40 cm soil layer.The content of soil organic matter in each treatment increased with the extension of application and showed a decreasing trend with soil depth.The content of available nitrogen increased in different soil layers with the continuous application in each treatment,and after 2 years,the available nitrogen contents in ST and MT in the soil layers of 0-20 cm and 20-40 cm were significantly higher than those in CT.Compared with CT treatment,MT and ST significantly increased the content of available iron in soil.MT was the highest in available iron the 0-20 cm soil layer,while in the 20-40 cm soil layer,ST was the highest.The changing trend of soil ammonium nitrogen content was different.It decreased gradually with soil depth in ST,BCT and MT.In CT,ammonium nitrogen was higher in the 0-20 cm and 40-60 cm soil layers than in the 20-40 cm soil layer.Besides,the content of ammonium nitrogen in MT was significantly higher than that in the other treatments in both the 0-20 cm and the 20-40 cm soil layers.The maximum nitrate nitrogen content was found in ST,MT and CT in the soil layer of 0-20,20-40 and 0-20 cm,respectively.The nitrate nitrogen content in MT in the soil layer of 40-60 cm was always significantly lower than that in ST.【Conclusion】According to the comprehensive evaluation by principal component analysis,three principal components with eigenvalues greater than 1 were extracted.The contribution rates of the principal components 1,2 and 3 were 58.67%,26.371% and 14.959%,respectively.The contribution rates of cumulative variance reached 100%,and the three principal components could reflect the information provided by all indicators.The comprehensive score of different fertilization treatments was in the order of MT>ST>BCT>CT,and MT had the best effect.