The paper concerns the transformation of water resources induced by the construction and functioning of the Brest Fortress defence structure and presents the current water resources resulting from these changes. The study was conducted by analysing historical materials: maps, plans and written documents. Hydrographic changes were analysed for five study periods covering almost 200 years, from 1823, presenting the hydrographic network before the construction of fortifications, up to 2018, when most of these structures ceased or were repurposed. Hydrographic changes were analysed in detail for the area of the Terespol Fortification. The analysis revealed that almost 80% of the wetland area had disappeared after intensive drainage works, and several dozen originally small and isolated areas had been incorporated into a vast drainage network. One of the consequences of these activities was the creation of significantly transformed artificial catchments within the study area.

The paper presents the characteristics of shallow groundwaters of the Polesie National Park – one of five national parks in Poland, where main subjects of protection are water-peatland ecosystems. Its functioning depends on the state of water resources. Data from field mapping at the turn of July and August 2013 used for the analysis show untypically high location of groundwaters in the summer period. Such a situation was caused by abundant atmospheric alimentation that occurred in spring and early summer of the analysed year.

The Włodawka River catchment of an area of 725 km2 covers the central and eastern part of the Łęczna-Włodawa Lake District. Evaluation of the role of hydrogenic areas in runoff creation was based on materials of the Department of Hydrography and the Institute of Meteorology and Water Management data. The analysis was conducted for selected catchments in which additional hydrometric measurements and water quality tests were done. Such parameters as: the share of hydrogenic surfaces in total catchment area, types of wetlands, their hypsometric location and position with reference to drainage streams were taken into consideration for evaluation. The degree of anthropogenic transformation of the marshland was expressed in terms of density and depth of the drainage ditches that dissect it. It was found that the drained gyttja of Krowie Bagno plays a considerable role in increasing the minimum discharge. Wetlands in the Włodawka River catchment influence the conditions of the runoff and water quality, which is noticeable, primarily, in the concentration of organic carbon, and of nitrogen and phosphorus compounds.

The suitability of a new wireless smart farming system for controlling irrigation and fertilization of horticultural plants was assessed in the study. The system (name: AGREUS®) includes sensors (soil moisture, salinity, weather data), executive modules (valve modules), and an application available on the web portal (accessed through computers and mobile devices). The studies were performed under laboratory and field conditions. Laboratory tests included appraisal of the precision of soil moisture and salinity measurements carried out with the soil probe (comparison with the results obtained by laboratory methods). Operational tests were conducted in field trials. In these trials, assessment of the possibility of practical control of irrigation and monitoring soil salinity was performed in an apple orchard. The conducted analyses have shown the usefulness of the system, not only for automatic control of irrigation but also for making decisions about the necessity to fertilize plants. The system enables continuous monitoring of changes in soil moisture and salinity, including the migration of minerals across the soil profile (using a probe with several measuring elements) as a result of the applied irrigation or rainfall. The system allows for automatic application of irrigation or fertigation depending on the adopted soil moisture and salinity thresholds. However, the tests showed that a salinity index calculated by the system does not directly correspond to the salinity values determined by laboratory methods. For this reason individual interpretation and determination of optimal ranges for plants is required.

Atmospheric precipitation is the major input to the soil water balance. Its amount, intensity, and temporal distribution have an indubitable influence on soil moisture. The aim of the study (conducted in the years 2010–2013) was to evaluate soil water balance in an apple orchard as determined by daily rainfall. The amount and intensity of rainfall and daily evapotranspiration were measured using an automatic weather station. Changes in soil water content was carried out using capacitance probes placed at a depth of 20, 40 and 60 cm. The most common were single events of rainfall of up to 0.2 mm, while 1.3–3.6 mm rains delivered the greatest amount of water. A significant correlation was found between the amount of daily rainfall and changes in water content of individual soil layers. The 15–45 cm and 15–65 cm layers accumulated the greatest amount of high rainfall. The study showed a significant influence of the initial soil moisture on changes in the water content of the analysed layers of the soil profile. The lower its initial moisture content was, the more rainwater it was able to accumulate.

The aim of the research was to evaluate effects of different rootstocks and management practices to counteracting replant disease in an apple orchard. The experiment was conducted in the Experimental Orchard of the National Institute of Horticultural Research in Dąbrowice, Poland, in 2014–2020. Apple trees of the cultivar ‘Ligolina’ were planted in autumn of 2013 at spacing of 3.8 × 1.4 m in the rows of an apple orchard that had been grubbed up in spring. The following experimental setups were used: (i) two types of rootstocks of different growth vigour (M.9, P14); (ii) replacement of soil in rows of trees with virgin soil; (iii) fertigation with ammonium phosphate; (iv) control (cultivation in the exhausted soil). Replantation significantly limited the growth of apple trees by reducing the cross- sectional area of the tree trunk, and the number and length of annual shoots. Fruit yields of apple trees grown on the replantation site were significantly lower than those of the trees grown in virgin soil. The use of ammonium phosphate fertigation had a positive effect on the growth and yield on the replantation site, especially when it was combined with the use of a stronger-growing rootstock (P14). The most effective environmentally friendly method of eliminating the apple replant disease is the replacement of the exhausted soil with virgin soil, i.e. soil that has not been used for growing fruit trees before.

A machine learning model was developed to support irrigation decisions. The field research was conducted on ‘Gala’ apple trees. For each week during the growing seasons (2009–2013), the following parameters were determined: precipitation, evapotranspiration (Penman–Monteith formula), crop (apple) evapotranspiration, climatic water balance, crop (apple) water balance (AWB), cumulative climatic water balance (determined weekly, ΣCWB), cumulative apple water balance (ΣAWB), week number from full bloom, and nominal classification variable: irrigation, no irrigation. Statistical analyses were performed with the use of the WEKA 3.9 application software. The attribute evaluator was performed using Correlation Attribute Eval with the Ranker Search Method. Due to its highest accuracy, the final analyses were performed using the WEKA classifier package with the J48graft algorithm. For each of the analysed growing seasons, different correlations were found between the water balance determined for apple trees and the actual water balance of the soil layer (10–30 cm). The model made correct decisions in 76.7% of the instances when watering was needed and in 87.7% of the instances when watering was not needed. The root of the classification tree was the AWB determined for individual weeks of the growing season. The high places in the tree hierarchy were occupied by the nodes defining the elapsed time of the growing season, the values of ΣCWB and ΣAWB.