The effect of vermicompost obtained from different cattle manures on some properties of soil and plant

This study was conducted to fill the knowledge gap regarding the comparative effects of vermicomposts derived from matured cow dung obtained from intensive livestock farming activities (OİG) and immature natural cow dung obtained from a farm practicing traditional animal husbandry, where animals have more freedom of movement (DİG). In the first phase of this thesis work, changes in enzyme activities (alkaline phosphatase, β-glucosidase, and urease) and mesophilic bacterial counts in vermicompost beds during the vermicomposting process of these manures were determined at regular intervals over approximately 8 months. The vermicomposting experiment consisted of 8 vermicomposting piles with 2 different feedstocks and 4 replicates. After this process, the biological and chemical analyses of the resulting vermicomposts (OİG-V and DİG-V) were performed to determine the differences and variations between them. In the second phase of the study, a pot experiment was conducted under greenhouse conditions to investigate the effects of vermicomposts produced using matured cow dung obtained from intensive livestock farming and immature natural cow dung obtained from a farm practicing traditional animal husbandry on soil and plants. The pot experiment consisted of a total of 24 pots, including 2 different vermicomposts (OİG-V and DİG-V), 2 different application rates for each vermicompost, a positive control with NPK application, and a negative control. The experiment was arranged in a completely randomized design, with curly lettuce used as the test crop. Bulk soil samples were taken in the 7th week and during harvest (9th week) of the experiment. Rhizosphere soil samples were also collected at the harvest (9th week). Biological parameters such as alkaline phosphatase, β-glucosidase, urease activities, and mesophilic bacterial counts were determined in these samples. In addition, macro and micronutrient analyses were performed on bulk soil samples taken during harvest. Macro and micronutrient contents, as well as agronomic parameters, were measured in the harvested plants. The type of organic waste was found to have an effect on the vermicomposting process, but the overall quality of the two vermicomposts obtained was similar. The OİG-V vermicompost was found to have higher levels of P, Ca, Mg, Mn, and Zn compared to the DİG-V vermicompost. In general, enzyme activity values were measured to be similar in both vermicomposts, with only β-glucosidase activity being higher in the DİG-V. The pot experiment showed that both vermicomposts stimulated microbial activity and increased pH, organic matter, P, and Zn values in the soil. However, the DİG-V vermicompost increased organic matter and P concentration in the soil to a greater extent. The impact of both vermicomposts on soil enzyme activities was generally more pronounced in the rhizosphere soil. β-glucosidase activity and mesophilic bacterial counts were similar in both vermicompost applications, but the DİG-V significantly affected alkaline phosphatase and urease activities in the soil. The effects of both vermicomposts on plant nutrient content were generally similar. However, the DİG-V significantly increased the plant's P content. Additionally, the DİG-V had a significant positive effect on agronomic parameters such as plant height, leaf area, and fresh and dry plant weight. In terms of fresh and dry root weight, both vermicomposts showed similar effects. In conclusion, although the OİG-V vermicompost was richer in certain nutrient elements compared to the DİG-V, it was found that the DİG-V was more effective on soil and plants. KEYWORDS: Vermicompost, cow dung, livestock farming, traditional husbandry, enzyme activities, mesophilic bacterial counts, rhizosphere, organic matter.