**5. Conclusions**

This study has provided information concerning the effects of a small group of trees on the microclimate components of a forest-steppe habitat. We observed the main characteristics and distribution of the dominant physical parameters of the abiotic edge effect [14], including the air temperature and air humidity in this habitat. The vapour pressure deficit is a susceptible indicator of the environmental conditions for vegetation. We successfully applied the duration curve method

on the VPD dataset. The VPD duration curves with thresholds of 1.2 kPa and 3.0 kPa were very informative in the spatio-temporal analysis, as the VPD exceedance rate could show the stress rate for the vegetation.

The cardinal and intercardinal directions as well as the altitude of the Sun have influences on the moderating and shading e ffects of the grove. With distance from the grove, the e ffects of other parameters increase significantly. We have also shown that not only the southern area could be consistently the warmest in a natural ecosystem.

We highlighted the importance of fine-scale sampling and analysis by demonstrating that the sample positions densely spaced in a continuous transect were able to reveal significant di fferences within small distances, which could be important in reassessing the structure of transition zones. In addition, they can uncover the patterns within seemingly homogeneous vegetation.

This knowledge is valuable for assessing the dynamics and spatio-temporal pattern of abiotic factors and physiognomy in this type of ecosystem, which is a natural transition zone in the temperate vegetation.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/1999-4907/11/10/1078/s1. Table S1: Zólyomi's T and W scales (TZ, WZ)—relative ecological indicator values for the optimum temperature and humidity.

**Author Contributions:** Conceptualization, L.K. and J.B.; methodology, G.S. and L.K.; software, S.F.; sampling, G.S., B.G., and L.K.; validation, L.K.; formal analysis, G.S. and L.K.; writing—original draft preparation, G.S.; writing—review and editing, L.K., J.B., and S.F.; visualization, G.S., S.F., and L.K. All authors have read and agreed to the published version of the manuscript.

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

**Acknowledgments:** We would like to thank the Institute of Ecology and Botany, Centre for Ecological Research, for use of the Fülöpháza research station. G.S., J.B., and S.F. acknowledge the support of the Higher Education Institutional Excellence Program (NKFIH-1159-6/2019) awarded by the Ministry of Human Capacities within the framework of water-related research of Szent István University.

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