The paper presents the results of the effects of control drainage (CD) on the groundwater table and subsurface outflow in Central Poland. The hydrologic model DRAINMOD was used to simulate soil water balance with drain spacing of 7 and 14 m, different initial groundwater Table 40, 60 and 80 cm b.s.l., and dates at the beginning of control drainage of 1 March, 15 March, 1 April, and 15 April. The CD restricts flow at the drain outlet to maintain a water table during the growing season. Simulations were made for the periods from March to September for the years 2014, 2017, and 2018, which were average, wet, and dry, respectively. The simulations showed a significant influence of the initial groundwater tables and date blocking the outflow from the drainage network on the obtained results. In the conditions of central Poland, the use of CD is rational only when it is started between 1 and 15 March. In this case, the groundwater table can be increased from 10 to 33 cm (7 m spacing) and from 10 to 41 cm (14 m spacing) in relation to the conventional system (free drainage-FD). In the case of blocking the outflow on 1 March, the reduction is about 80% on average in the period from March to September. With a delay in blocking the outflow, the impact of CDs decreases and ranges from 8% to 50%. Studies have shown that the proper use of the drainage network infrastructure complies with the idea of sustainable development, as it allows efficient water management, by reduction of the outflow and, thus, nitrates from agricultural areas. Furthermore, CD solutions can contribute to mitigating the effects of climate change on agriculture by reducing drought and flood risk.Sustainability 2019, 11, 4201 2 of 18 water users to be affected by the consequences of climate change in different way [5]. Consequently, this will lead to exacerbated competition among water users and sectors [6].One of the main challenges for sustainable development is the adaptation of national economies to climate change. Most often, climate change adaptation projects in Poland are carried out in cities and areas subject to urban sprawl [7][8][9]. Agriculture is a key sector for food supply, and its functioning depends largely on access to water. It is, therefore, necessary to take various actions to protect this sector of national economies against climate change. The most frequently asked question is whether and to what extent it is possible to take action in the adaptation of agriculture to climate change while maintaining high environmental standards and accounting for the acceptance of society and economic balance.The greatest scope for the mitigation of the effects of climate change is in improving adaptive capacity and responding to changes in water demands [10]. Agricultural subsurface drainage, popularly known as tile drainage, is an essential water management practice in agricultural regions with seasonal high groundwater tables [11]. Around 193.9 × 10 6 ha of arable land, and permanent crops have been drained around the world. In 30 countries, th...

Our paper presents the possibility of applying the DRASTIC model as a useful tool to support the process of local and regional development planning. The study was carried out in the catchment of Stare Miasto Reservoir in Central Poland. In order to plan the policy to protect the reservoir and groundwater, the assessment of groundwater vulnerability to pollution was made by means of the DRASTIC model. The original model was modified by adding a new parameter called "land use." The measured nitrate concentrations were used to test the original and modified models. The results of the study revealed that the modified DRASTIC model gave more accurate predictions than the traditional model. The Pearson correlation coefficients characterising the relationship between the vulnerability index and the nitrate concentration was 0.56 before the modification and 0.69 after it. The groundwater vulnerability map is necessary for planning local development and for assessing environmental impact. The DRASTIC model is expected to be a useful tool for designing programs and strategies, e.g., for improving the quality of surface water and groundwater.

The paper presents the results of time-related changes in maximum temperatures in lakes. The analysis was carried out on the basis of 9 lakes located in the northern part of Poland. The analysis was based on daily water and air temperatures in the period 1971–2015. Mann–Kendall's and Sen's tests were applied to determine the directions and rates of change of maximum air and water temperatures. The average increase of maximum water temperature in analysed lakes was found to be 0.39 °C dec–1, while the warming trend of the maximum air temperature was 0.48 °C dec–1. Cluster analysis (CA) was used to group lakes characterised by similar changes of maximum water temperature. The first group included five lakes in which the values of the maximum temperature trends were 0.41 °C dec–1. In the second cluster the average value of maximum water temperature increase was smaller than in the first cluster (0.36 °C dec–1). Comparing the results of cluster analysis with morphometric data show that in the first cluster lakes are having a greater average depth, maximum depth and water transparency in comparison to the lakes of the second cluster.

Control drainage (CD) is a common practice implemented to control the water balance of drainage fields by increasing the amount of water retained in soil. Worldwide studies suggest that climate change can reduce the effectiveness of CD solutions, but no study of CD effects has been carried out in Polish conditions yet. In this study, the DRAINMOD (Wayne Skaggs, North Carolina State University, Raleigh, USA) computer simulation model was used to predict the effects of CD on the time horizons of 2021–2050 (near future) and 2071–2100 (far future) assuming the Representative Concentration Pathway (RCP) 4.5 emission scenario. The effectiveness of CD solutions is presented for a drainage network with spacing of 7 or 14 m. Additionally, different dates of blocking the outflow from the drainage network (1st and 15th of March and 1st and 15th of April) and different initial groundwater table conditions (0.4, 0.6, and 0.8 m) were assumed. All simulations for different variants were carried out for the same period, i.e., from 1st of March to 30th of September. The results of climate models indicated that in the area of central-western Poland in the near and far future there will be an increase in air temperatures by 1.02 and 1.97 °C, respectively, and in precipitation by 5.98% and 10.15%, respectively. In addition, there will be a change in the structure of precipitation, especially with respect to the extension of rain-free periods and an increase in the amount of extreme daily precipitation. The effect of climate change will be a decrease in the mean groundwater table in the fields equipped with drainage systems from 2 to 5 cm. In addition, the number of days on which groundwater table will be above the level of the drainage network will decrease. For the drainage network with spacing of 7 m, the time of the groundwater table above the level of the drainage network will decrease by 5 and 7 days in the near and far future, respectively, while for the drainage network with spacing of 14 m, it will decrease by 4 and 7 days. Climate change will also reduce sub-surface outflow. Subsurface outflows will be smaller than those currently recorded on average by 11% and 17% and 12% and 18% for 7 m and 14 m spacing drainage networks, in the near and far future, respectively. The increase in rainfall intensity in the near and far future will result in a fivefold increase in surface outflow in comparison to the present situation. The simulations show that the greatest effectiveness of CD solutions will be achieved by starting the blocking of outflow from the drainage network on the 1st of March. The implementation of CD solutions since April in the near and far future will allow maintaining the groundwater table at the level presently observed for the conventional network (free drainage-FD).

Open‐cast mining of lignite leads to considerable degradation of the natural environment, which then must be reclaimed. The aim of this study was to assess the transformation of Technosols in an area after lignite mining which had been under 40‐year cultivation of alfalfa with grass at various NPK fertilization rates. We hypothesized that 40‐year cultivation of plants caused morphological transformation of the parent material and resulted in differentiation of physical and chemical properties in the profile of the Technosols; fertilization had an added advantageous effect on their properties. The surface layer was transformed into an Ap‐horizon. Under alfalfa, with grass and NPK fertilization, Ap‐horizons demonstrated lower bulk density (BD) (7–11%) and particle density (PD) (1–2%), and higher total porosity (TP) (18–35%), drainable porosity (DP) (2–94%), field water capacity (FC) (11–21%), unavailable water (UW) (4–17%), soil organic carbon (SOC) (80–142%), total nitrogen (TN) (261–330%), available P (39–435%), available K (32–89%), cation exchange capacity (CEC) (25–43%), and soil acidity (Hext) (42–81%) compared to Cd‐horizons. Fertilized Technosols (1NPK, 2NPK), compared with control (0NPK), showed in the Ap‐horizon an increase in SOC (18–35%), TP (8–15%), DP (81–90%), FC (9–10%), P (110–285%), K (14–71%), and TN (0–18%), and a decrease in BD (4–7%). In contrast, fertilization had no effect on the UW, PD, soil inorganic carbon (SIC), CaCO3, available Mg, and pHKCl. The alfalfa and orchard grass played a key role in the reclamation and soil‐forming processes, while fertilization played a supporting role.