## 4 Discussion
Their migration, persistence and synergistic effect mean that they can significantly affect microbial activity by disrupting the correct sequence of biochemical pathways in the biogeochemical cycles of soil [13; 20; 34]. Moreover, according to [PERSON] et al. [35] the application of herbicides to soil stimulated the activity of microorganisms; however, it will depend on the properties of the herbicide as well as agotechnical treatments, the physicochemical properties of the soil, the date of its application, and also on climatic conditions. On the other hand, as reported by [PERSON] et al. [34] the application of fungicides onto plants may disrupt their metabolic pathways by altering the photosynthetic pathway as well as disrupting soil biological homeostasis and altering the diversity and structure of their community. In our own research, on the plots where the F, H and F + H treatments were applied, an increase in the activity of DHA and URE was observed, which could be due to the fact that the microorganisms could actively use the introduced herbicides/fungicides as an additional source of carbon necessary for their growth and development. However, the effect of pesticides on soil enzyme activity is inconclusive according to the literature data. [PERSON] et al. [36] found no effect of mesotrione on the activity of URE but [PERSON] et al. [37] observed positive influence of glyphosate on URE activities. [PERSON] et al. [38] showed that azoxystrobin significantly inhibits changes in enzymatic activity for URE and CAT, but no decreasing effect on DHA was obtained. In turn, [PERSON] et al. [39] observed in their research that after the application of fomesafen, the activity of URE was inhibited, while it had no significant influence on the activity of CAT. In our research, in the case of CAT, the F, H and F + H treatments reduced the activity of this enzyme, which suggests that microorganisms that had the ability to decompose thiophanate-methyl and azoxystrobin could have displaced those species that were responsible for CAT activity in soil. Moreover, as was indicated by literature data and own research, the activity of soil enzymes in soil largely dependent on the active substance of the pesticide. The fingerprint technique--TRFLP analysis was used in the studies on the biodiversity of soil bacteria and fungi. It is an indirect method that allows for assessing the dynamics of the community of soil microorganisms depending on changes in environmental conditions, including the presence of pollutants [40]. Our research showed that various agrotechnical treatments (organic fertilization; the application of pesticides) can affect the richness and diversity of soil microflora, which was also confirmed in the research conducted by [PERSON] et al. [41]. In addition, studies by [PERSON] et al. [3], in which the popular herbicide (glyphosate) was used, showed that the application of this agent may reduce the genetic biodiversity of bacteria and at the same time affect the growth of fungi biodiversity over time. In the present research study, the determined indicators of biodiversity for bacteria (H\({}^{\prime}\) and Margalef indices) in variants with F and H are significantly lower than in the control, while in the case of fungi, this relationship applies to almost all research variants (excluding \(\rm{GSS+F+H}\)). There was also no observed increase in the biodiversity of fungi as compared to bacteria, which does not support the previous studies on glyphosate. Moreover, the authors' own research showed a beneficial effect of the sludge applied simultaneously with the herbicide and fungicide on the level of diversity of the bacterial population. A lower effect was noticed in case of fungi. It can be assumed that nutrients such as C, N and P contained in sewage sludge as well as micronutrients may improve the activity of soil microorganisms and thus eliminate the negative impact of pesticide application. Moreover, according to [PERSON] et al.