Title : Modeling of the processes of accumulation of nutrients when using organic waste as fertilizers on sod podzolic soils
Abstract:
To evaluate the fertilizing and toxicological properties of organic compost enriched with municipal wastewater sludge for their use in agriculture. To construct a mathematical model of the effect of compost enriched with sewage sludge on the agrochemical parameters of the soil. The study was conducted by setting up model laboratory and long-term field experiments. The object of the study was sewage sludge from sewage treatment plants in the Leningrad region, coal ash from thermal power plants in St. Petersburg and peat compost based on them.
According to the results, the studied municipal waste contained nutrients. Composting sewage sludge with peat brought the amount of toxic substances contained in them to established standards and created conditions acceptable for growing plants. The amount of nutrients in the compost increased with an increase in the amount of waste in it. The use of this compost on sod-podzolic soil led to an accumulation of organic matter by 45% and mobile phosphorus by more than two times relative to the control. The data obtained in the field experiment allowed us to build a mathematical neural network model of the effect of compost enriched with sewage sludge on soil agrochemical parameters.
Conclusions. It is advisable to use sewage sludge in the form of compost with a peat: waste ratio of 1: 0.25. The introduction of compost into sod-podzolic soil increased the content of organic matter and mobile phosphorus in it, without changing the acidity of the soil. A mathematical neural network model of the effect of municipal waste on agrochemical parameters of sod-podzolic soil can be used to predict changes in the characteristics of these soils when using organic compost from municipal waste in human economic activity.
