| Accelerating the resource utilization of agricultural by-products and promoting the efficient and high-quality development of agricultural mechanization are effective ways to achieve green and low-carbon development of agriculture and promote the conservation and utilization of black land.In this study,in order to improve the mechanization efficiency of nodulated vegetable seedling transplanting and reduce the environmental pollution caused by the waste of plastic seedling pots,the key technology of manufacturing rice straw fiber-based Cruciferous Vegetable seedling pot material is studied experimentally with rice straw as the main raw material,and the degradation performance of seedling pot material during the seedling transplanting period is explored initially,the structure of seedling tray is optimized and designed,and its production process is given,and the application effect of the seedling pot is studied by multiple comparative analysis.The study of a kind of Cruciferous Vegetable seedling tray with rice straw fiber-based to meet the requirements of mechanized transplanting and degradability.The main research contents and results are as follows:(1)Optimization of manufacturing parameters and experimental study of rice straw fiber-based seedling pots.Rice straw was used as the main raw material,and five factors and five levels(1/2 full implementation)quadratic regression orthogonal rotation center composite experimental method was used.Beating degree of rice straw fiber,quantity,proportion of rice straw fiber,neutral sizing agents mass fraction,and wet strength agent mass fraction were selected as test factors,and performance evaluation indexes such as dry tensile strength,wet tensile strength,burst strength,tear strength,air permeance,and degradation period were taken as response functions.The influence law of each factor on the response function and the optimization combination of material manufacturing process parameters were studied.The results show that:When the parameters were beating degree of rice straw fiber 50±1°SR,quantity87.5±4 g/m~2,proportion of rice straw fiber 70%,neutral sizing agent mass fraction 1±0.25%and wet strength agent mass fraction 1.5±0.1%,the dry tensile strength of the obtained material≥1.8 k N/m,wet tensile strength≥0.7 k N/m,burst strength≥140 k Pa,tear strength≥350 m N,air permeance≤1.33μm/Pa·s,degradation period≤80 d.Dry tensile strength degradation rate of 0.0274(k N/m)/d and wet tensile strength degradation rate of 0.0113(k N/m)/d when applied to Cruciferous Vegetable seedlings;The dry tensile strength and wet tensile strength were≥1 k N/m and≥0.4 k N/m during the seedling period[30,40]days.The material of rice straw fiber-based seedling pots can meet the technical requirements of agronomy and mechanical transplanting.(2)Degradation performance research of rice straw fiber-based seedling pots materials.The changes of microstructure,chemical composition and mechanical strength of the material during degradation were analyzed.The degradation performance of the material was preliminically studied by means of SEM observation,FT-IR analysis,material degradation rate determination,cellulose,hemicelluloses and lignin determination,and dry and wet strength changes of the material during the seedling period.The results show that:At 40 days of grow seedlings,the material mass decreased by 0.27g,including cellulose by0.12g,lignin by 0.15g,hemicellulose by no significant reduction,dry tensile strength decreased by 54.87%to 0.13 k N/m,wet tensile strength decreased by 59.6%to 0.4 k N/m.(3)Structure optimization design and production process of Cruciferous Vegetable band disc-shaped seedling pots with rice straw fiber-based.Combined with the requirements of transplanting mechanical seedling pots,the single pot and winding mode of rice straw fiber-based Cruciferous Vegetable band disc-shaped seedling pots tray were analyzed and designed theoretically.The single pot of the seedling pots tray is a hexagonal prism with a side length of 25mm and a height of 100mm,and the winding mode of the pot belt is clockwise.Based on the pot material manufacturing and the design of the seedling pots tray,the manufacturing process of the Cruciferous Vegetable band disc-shaped seedling pots with rice straw fiber-based is given.(4)The effects of rice straw fiber-based seedling pot,plastic seedling pot and bare ground on plant growth during the seedling transplanting period were studied by multiple comparative analysis.The plant height,plant fresh weight,plant root dry weight and leaf width were used as evaluation indexes,and the data were statistically analyzed by multiple comparison method.Compared with plastic seedling pot and bare ground seedling,rice straw fiber-based seedling pot plant growth and development is better and the plant root system growth and development is less affected,and can be completely degraded after the end of transplanting,shortening the retardation period.Compared with plastic seedling container and bare soil seedling,seedling pots with rice straw fiber-based plant growth and development is better,the plant root system growth and development is less affected,and can be completely degraded after the end of transplanting,shortening the slowing period. |
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