Changes In Characters During The Fermentation Of Cassava Residues And R&D Of Vegetable Substrates

Cassava residues,the waste material of the fuel ethanol and starch processing industry,is mainly composed of crust external skin and internal parenchyma.China’s annual fuel ethanol,starch processing and other industries can produce up to 1.5 million tons of cassava slag.However,the dispose of cassava residue is lack of very effective measures.In addition,cassava residue is rich in a variety of nutrients.Thus,arbitrary disposal is not only a waste of resources,but also poses a certain threat to the environment,especially the protection of water resources and atmosphere.The formation of crop cultivation and seedling growth substrates through biological fermentation is an effective way to recycle organic solid waste such as cassava residues.In this paper,the change of physicochemical properties in the process of cassava dregs fermentation was studied,and the cassava dregs and peat,vermiculite,and perlite were mixed in a certain volume ratio.The experiments were carried out on vegetable cultivation and cultivation,and the cassava dregs were selected.Nursery and cultivation substrate formulations.The main findings are as follows:1.In the biofermentation process of cassava dregs,the highest temperature reached 65.8℃ on the 10th day of fermentation,and then the whole showed a downward trend.At the 34th day of fermentation,the temperature was basically stabilized;the pH increased first and then decreased.As a result the pH of the compost quickly increased to 6.98 on the 4th day of the fermentation,and then began to decline.It reached a minimum value of 6.48 on the 28th day of the fermentation,and finally stabilized;the EC value as a whole rose first and then decreased and stabilized.The changes of TDS,SAL and EC values were consistent.On the 23rd day of fermentation,the EC values,TDS,and SAL of the reactor reached the maximum,which were 5.9 mS·cm-1,2.93 g·L-1,and 3.17 psu,respectively.Afterwards,the overall trend showed a downward trend,reaching the lowest values on the 30th day of the fermentation,which were 5.15 mS·cm-1,2.54 g·L-1 and 2.75 psu,respectively,and basically stabilized afterwards;As the trend stabilized,the bulk density of the bulk reached a maximum of 0.56 g·cm-3 on the 34th day of the fermentation,and then it basically stabilized;the overall porosity did not change substantially,and it remained at around 65%;ventilation porosity followed After the gradual decline of the fermentation,it tends to be stable,and the fermentation proceeds.On the 34th day,the aeration porosity reached a minimum value of 1%,and then it basically stabilized;the water holding porosity gradually increased and then stabilized,reaching a maximum of 64%on the 19th day of fermentation,and then showed a downward trend in fermentation.It basically stabilized after 34 days.Organic matter content gradually decreases with the progress of fermentation and tends to be stable.2.Fully fermented and completely cooked cassava residues were used as the main raw material,and 12 different cassava residue matrix ratios were compounded with peat,vermiculite,and perlite according to a certain volume ratio.The commercial vegetable seedling substrate in the market was used as a control.The physicochemical properties of the matrix of cassava slag and its effect on the growth of different types of fruit and vegetable vegetables were screened out,and the matrix formulation of cassava scum for cucumber,tomato and watermelon was selected.The results showed that the physical and chemical properties of the cassava slag compound matrix with the ratios of 40:40:10:10(T5 treatment)and 20:40:20:20(T6 treatment)of cassava residue,peat,vermiculite and perlite.In the suitable range of growth requirements for vegetable seedlings,the seedling emergence rate,seedling index,chlorophyll content,root vigor,root volume,number of apical roots and other growth indicators of the melon and fruit vegetables grown in the two matrix formulas were higher than other cassava residue matrixes.Formulations and controls.According to the growth status of vegetable seedlings,combined with environmental and economic factors,it is recommended to use T5 treatment with a higher proportion of cassava residues as a special formulation for cucumber seedlings,and T6 treatment can be used as a generic seedling formulation for fruit and vegetable vegetables.Fully fermented and completely cooked cassava residues as the main raw material,and peat,vermiculite,and perlite were mixed into 11 different cassava residue matrix ratios according to a certain volume ratio,and compared with the commercial vegetable cultivation matrix on the market,different cassava residues were studied.The physical and chemical properties of the matching substrate and its effect on the growth,yield and quality of the cucumber were selected and the formula of the cultivation substrate suitable for the growth of cucumber was selected.The results showed that the physical and chemical properties of the cassava slag compound matrix with the ratio of cassava slag,peat,vermiculite and perlite of 30:30:20:20(T4 treatment)and 40:40:10:10(T6 treatment)Within the suitable range of vegetable cultivation requirements.Moreover,the cucumber planted with two cassava residues was cultivated in terms of plant height,stem diameter,plant height,stem diameter,leaf number,leaf area,leaf chlorophyll content,photosynthetic characteristics,yield,fruit quality and other indicators.All aspects are better than the control,combined with environmental and cost factors,it is recommended to use T4 treatment with a lower proportion of grass charcoal as a cucumber cultivation matrix.