**4. Conclusions**

The composition of the soil fauna, according to the influence of the organisms on agriculture, is 84% beneficial fauna, 8% agricultural pests and 8% indifferent fauna. Overall, 47% of the total individuals of beneficial fauna collected were spiders, which are the most abundant predators in the soil layer and can play an important role in reducing pest population in large numbers. Bioindicator species such as ground beetles have not received much attention from researchers in Croatia, although they can indicate anthropogenically influenced field quality. In this study, we gained detailed knowledge about their community in a specific agricultural landscape in central Croatia. In modern agriculture, conservation programs are promoted to preserve useful species and biodiversity as a means to ensure sustainability.

The number of total fauna collected was influenced by the interaction between presowing intervention and sampling date. Pre-seeding interventions (such as cover crops, glyphosate application, and mulching) that did not involve soil activities did not affect the number and composition of soil fauna in the beginning of the vegetation. Mechanical intervention in the soil and warmer and drier weather (summer/fall) have a negative effect on the number and composition of soil fauna. As the season progresses, the influence of pre-sowing activities on soil fauna in soybean production decreases.

There are two main reasons for the difficulty in relating soil fauna activities to ecosystem and agricultural services: first, the top-down effects of management, especially in agricultural systems; second, the specificity of soil processes. In highly diverse communities, the abundance of specific soil fauna members' effects is masked by the other biotic events that contribute to the same properties and processes in soil (e.g., weather conditions. Many processes created by soil fauna (predation, symbiosis, mutualism, etc.) have dynamics that can nullify the signal of the soil intervention effects studied during one soybean season.

However, the results of this study contributed significantly to a better understanding of the baseline situation about soil fauna communities in an intensive agricultural landscape and will be a good starting point for future studies and conservation programs.

**Author Contributions:** Conceptualization, D.L. and M.P.; methodology, D.L. and R.B.; software, D.L.; validation, I.P.Ž., and R.B.; formal analysis, D.L. and M.P.; investigation, M.P.; resources, R.B.; data curation, M.P.; writing—original draft preparation, D.L., M.P. and I.P.Ž.; writing—review and editing, D.L. and I.P.Ž.; visualization, D.L. and I.P.Ž.; supervision, D.L. and R.B. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

**Acknowledgments:** We thank Iva Dobrinˇci´c, Matej Oreškovi´c, Marija Andrijana Galeši´c, Sandra Skendži´c, Kristina Žganec and Maja Šupljika for help in the collection and determination of soil fauna. Special thanks to Josip Laki´c for providing us soybean fields for this survey.

**Conflicts of Interest:** The authors declare no conflict of interest.
