5种热带农业废弃物好氧堆肥过程中的变化及堆肥产物施用效应分析

Changes of five tropical agricultural wastes during aerobic composting process and analysis on application effects of the compost products

为了探明中国热带地区农业废弃物的堆肥效果及堆肥产物的施用效应,对海南省5种典型农业废弃物(包括蔗渣、橡胶木屑、椰糠、菠萝叶和木薯杆)好氧堆肥过程中温度、养分含量和堆肥腐熟度指标的变化进行了比较,并分析了不同堆肥产物对连茬小白菜(Brassica campestris subsp.chinensis Makino)单株干质量及土壤主要理化指标的影响。结果表明:5种农业废弃物的好氧堆肥过程均可分为升温期、高温期、降温期和腐熟期4个阶段,高温期可持续6~11 d。堆肥28 d,5种农业废弃物的pH值(pH 7.81至pH 8.55)、电导率(1575~3604μS·cm^(-1))及堆肥产物培养的小白菜种子发芽指数(106.7%~140.0%)均达到NY/T 525—2021公布的腐熟标准。堆肥前后的养分含量总体上存在显著(P<0.05)差异,堆肥后有机质、全氮、全磷、全钾和总养分含量分别为40.46%~47.26%、1.82%~2.28%、1.96%~2.62%、1.45%~2.04%和5.74%~6.31%。与无肥料处理组和化肥处理组相比,5个堆肥产物处理组土壤的有机质、全氮、碱解氮、有效磷和速效钾含量以及pH值和总孔隙度总体上显著升高,土壤容重却显著降低,蔗渣、橡胶木屑和椰糠堆肥产物处理组的小白菜单株干质量显著升高。综上所述,供试5种农业废弃物的堆肥效果总体较好,其中,蔗渣、橡胶木屑和椰糠堆肥产物对小白菜的增产效果较好。

In order to clarify the composting effects of agricultural wastes in tropical areas of China and the application effects of the compost products,the changes of temperature,nutrient contents,and compost maturity indexes of five typical agricultural wastes(containing bagasse,rubber sawdust,coconut husk,pineapple leaf,and cassava stalk)in Hainan Province during aerobic composting process were compared,and the effects of different compost products on dry mass per plant of continuous cropping Brassica campestris subsp.chinensis Makino and main physicochemical indexes of soil were analyzed.The results show that the aerobic composting processes of five agricultural wastes all can be divided into four stages,namely mesophilic stage,thermophilic stage,cooling stage,and maturity stage,and the thermophilic stage can last 6-11 d.When composting for 28 d,the pH value(from pH 7.81 to pH 8.55),electrical conductivity(1575-3604μS·cm^(-1)),and germination index(106.7%-140.0%)of B.campestris subsp.chinensis seeds cultivated with compost products all reach the rotten maturity standard announced by NY/T 525-2021.There are significant(P<0.05)differences in nutrient contents between before and after composting in general,and the contents of organic matter,total nitrogen,total phosphorus,total potassium,and total nutrients after composting are 40.46%-47.26%,1.82%-2.28%,1.96%-2.62%,1.45%-2.04%,and 5.74%-6.31%,respectively.Compared with no fertilizer treatment group and chemical fertilizer treatment group,the contents of organic matter,total nitrogen,alkali-hydrolyzable nitrogen,available phosphorus and available potassium,pH value,and total porosity of soil of five compost products treatment groups significantly increase in general,but the soil bulk density significantly decreases,and the dry mass per plant of B.campestris subsp.chinensis of bagasse,rubber sawdust,and coconut husk compost product treatment groups significantly increase.In conclusion,the composting effects of five test agricultural wastes are relatively good in general,in which,the yield-increasing effects of compost products of bagasse,rubber sawdust,and coconut husk on B.campestris subsp.chinensis are relatively good.