In an upland forested micro-catchment during the growing season, we tested soil responses to precipitation events as well as soil water content (SWC). We asked ourselves if what is the difference of SWC response to precipitation events depending on the presence and proximity of a tree? The environmental heterogeneity of the small 7.5-ha headwater area was captured by soil probes at specific locations: (i) probe measurements of SWC at 10-, 30-, 60-, and 100-cm depths; (ii) resolution of near-tree (NT) and between-tree (BT) positions; and (iii) resolution of four slope classes. The results revealed significant differences between the hydrological responses of the soil. NT soils had faster infiltration but were also faster to dry out when compared to BT soils, which were less affected by the presence of trees. Water input threshold values, measured as the precipitation amount needed to cause a significant increase in SWC, were also significantly different, with NT positions always lower than BT positions. Total infiltration of the topmost NT and BT soil layers reached 185 and 156 mm during the study period, corresponding to 43% and 36% of the total 434 mm of precipitation, respectively. Infiltration into the deepest horizon was significantly higher in NT soils, where it reached 114 mm (26%) as opposed to 9 mm (2%) in BT soils, and was indicative of significant vertical hydraulic bypass flow in the proximity of trees. These observations contribute to better understanding the hydrological processes, their nonlinearity, and the expansion of conceptual hydrological models.

In the last two decades, the effects of global climate change have caused a continuous drying out of temperate landscapes. One way in which drying out has manifested is as a visible decrease in the streamflow in the water recipients. This article aims to answer the questions of how severe this streamflow decrease is and what is its main cause. The article is based on the analysis of daily streamflow, temperature, and precipitation data during five years (1 November 2014 to 31 October 2019) in a spruce-dominated temperate upland catchment located in the Czech Republic. Streamflow values were modeled in the PERSiST hydrological model using precipitation and temperature values obtained from the observational E-OBS gridded dataset and calibrated against in situ measured discharge. Our modeling exercise results show that the trend of decreasing water amounts in forest streams was very significant in the five-year study period, as shown in the example of the experimental catchment Křtiny, where it reached over −65%. This trend is most likely caused by increasing temperature. An unexpected disproportion was found in the ratio of increasing temperature to decreasing discharge during the growing seasons, which can be simplified to an increasing trend in the mean daily temperature of +1% per season, effectively causing a decreasing trend in the discharge of −10% per season regardless of the increasing precipitation during the period.

The aim of this article is to present the basic theses about the function and potential of infiltration pits under culvert mouths on forest roads. The methodology consisted of a combination of literature review and own in situ experiments. Experimental verification was carried out on sections of forest roads on two training forest enterprises (TFE) at Kostelec nad Černými lesy and Masarykův les Křtiny (Czech Republic). At each location, two infiltration pits were built in a paired design with a uniform retention volume. One of the pits was always located under a pipe culvert. The control pit was located approx. 30 m far from it, in the same pedological and vegetation conditions without a centralized inflow. Measurements from the study period (autumn 2022) indicated that the infiltration pits under the culverts had unexpectedly low efficiency in retaining and infiltrating surface runoff. Mostly, due to the fact that in the analyzed period the surface runoff was minimal, even though precipitation did occur. During the study period, the infiltration pits did not reach the expected potential to support the hydric regime of the landscape.

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