## 3 Results and Discussion
### Soil Physical Quality Assessment  
Two of the six SPQ indicators (_OC_ and _SSI_) were directly measured, while the remaining four (capacitive indicators) were derived using the BEST procedure.  
The investigated soil had a poor content of organic matter, with a mean _OC_ value of 15.7 g kg\({}^{-1}\). Also, the low value of the structural stability index (_SSI_ = 5.7%) indicates a high risk of soil degradation. These results suggested that the soil was prone to mechanical breakdown of aggregates and the occurrence of sealing phenomena, for instance during intense rainfall events [55]. This hypothesis was corroborated by the observation, during the winter season and in the proximity of the sampled plot, of depositional seal layers. These thin and dense surface layers resulted from the transport of particles physically dispersed by the impacts of raindrops [56]. The particles were carried in suspension by runoff, which may be generated by the above-described mechanism, and finally deposited in correspondence with surface depressions [57].  
Figure 4 shows the BEST-deduced water retention curve and the estimated values of the selected capacitive soil physical quality indicators. While the \(\theta_{TI(h=-30)}\) and \(\theta_{s}\) values were measured from wet soil samples collected, respectively, after the tension and Beerkan infiltration tests, the other parameters (\(\theta_{PWP}\), \(\theta_{FC}\), and \(\theta_{m}\)) were determined from the water retention curve using the mean values of the BEST-deduced shape (\(n\) and \(m\)) and scale (\(\alpha\)) parameters. Almost identical values of the soil water content at the permanent wilting point (\(\theta_{PWP}\) = 0.12 m\({}^{3}\) m\({}^{-3}\)) and field capacity (\(\theta_{FC}\) = 0.22 m\({}^{3}\) m\({}^{-3}\)) were reported by [PERSON] et al. [58] for the soil at the Ottawa experimental station, thus increasing our confidence in the BEST-deduced parameters. The findings revealed that the soil under study exhibited significant soil aeration and macroporosity (represented by _AC_ and \(p_{MAC}\)), while indicators related to microporosity (such as _PAWC_ and _RFC_) were notably low. A low _RFC_ indicates the soil's limited capacity to retain water compared to its total pore volume. _RFC_ values below 0.6 may lead to decreased microbial activity due to inadequate soil moisture (water-limited conditions) [27]. A diminished _PAWC_ indicates a scarcity of micropores ranging from 0.2 to 30 \(\mu\)m in diameter, which typically hold water accessible to plant roots within the total porosity [4]. Soils with 0.10 \(\leq\)_PAWC_ < 0.15 m\({}^{3}\) m\({}^{-3}\) are frequently categorized as drought-prone [27]. These observations imply that the uppermost soil strata support root growth and efficiently drain surplus water into the underlying limestone layer, yet exhibit restricted capacity to retain and supply water to plant roots.  
Figure 4: \(\theta_{PWP}\) [m\({}^{3}\) m\({}^{-3}\)] is the permanent wilting point soil water content, corresponding to \(h=-150\) m. \(\theta_{FC}\) [m\({}^{3}\) m\({}^{-3}\)] is the field capacity (gravity drained) soil water content, corresponding to \(h=-1\) m. \(\theta_{m}\) [m\({}^{3}\) m\({}^{-3}\)] is the saturated volumetric water content of the soil matrix, corresponding to \(h=-0.1\) m. \(\theta_{TI}\) [m\({}^{3}\) m\({}^{-3}\)] is the final volumetric water content at the end of the TI test (corresponding to \(h=-0.03\) m), \(\theta_{s}\) [m\({}^{3}\) m\({}^{-3}\)] is the saturated volumetric water content. _AC_ [m\({}^{3}\) m\({}^{-3}\)] is the air capacity. _PAWC_ [m\({}^{3}\) m\({}^{-3}\)] is the plant-available water capacity. _RFC_ [\(-\)] is the relative field capacity. _pMAC_ [m\({}^{3}\) m\({}^{-3}\)] is the soil macroporosity. \({}^{\dagger}\) Water content values determined from wet soil samples collected after the tension (\(\theta_{TI}\)) and Beerkan (\(\theta_{s}\)) infiltration tests.