This study aims at exploiting research outcomes concerning tillage practices in order to make solutions available to farmers to mitigate negative environmental impact to soils. Two alternative practices have been analysed against conventional full tillage based on data provided by a long-term experiment conducted at the Institute of Soil Science and Plant Cultivation (IUNG) farm in Grabów, Central Poland. Reduced Tillage and Direct Sowing are evaluated against Full Tillage on the basis of socio-economic and environmental criteria. Multi-criteria decision analysis undertaken using the PROMETHEE method provided evidence that the ‘optimal’ maize cultivation system depends on the decision maker’s viewpoint and preferences. In fact, criteria selected and related weights elicited from representative farmers, as well as from an expert agronomist, reveal different viewpoints. Direct sowing was the most preferable for the large farm and expert perspective, whereas in case of small farm reduced tillage ranked first. Prospect theory developed by behavioural economists was incorporated to take into account decision biases. As a matter of fact, based on Prospect Theory-PROMETHEE from the small farm and the expert perspective, the conventional system was now ranked first, while for the large farm, the most preferable practice was still direct sowing.

In this study, we identify the spatial distribution of water deficits in Poland. The analyses considered expert knowledge in soil categories importance in water stress evaluation influencing the climate suitability for maize production using the analytical hierarchy process (AHP). The Climatic Water Balance was calculated from April to September, for the baseline (BL) period (1981–2010) and two future periods of 2041–2070 (2050s) and 2071–2100 (2080s) using a six-member ensemble of GCM-RCM chain simulations under two representative concentration pathways (RCP) scenarios: low emissions (LE, RCP4.5) and high emissions (HE, RCP8.5). Taking into consideration water deficiency for the BL period, about 81% of Poland proved highly suitable, 18% moderately suitable and 1% marginally suitable for maize cultivation. According to LE and HE scenarios, the area of Poland that is highly suitable for maize production would decrease to 67 and 69% by the 2050s, and to 64 and 44% by the 2080s. By the 2080s, under the HE scenario, rain-fed maize production would become risky, as 21% of Poland would be marginally suitable, while 11% would not be suitable. According to our findings, supplemental irrigation is one of the effective adaptation strategies to maintain the production potential of maize in Poland.

This article presents selected flow modeling indices of the Bystra River catchment area (east Poland) obtained using the SWAT model simulations for three regional climate models driven by the EC-EARTH global climate model for 2021–2050 and both RCP4.5 and RCP 8.5 scenarios. The research area was selected due to the large relief of the terrain, the predominance of soils made of loess and the agricultural nature of the Bystra River catchment area, which is very sensitive to climate change, has very valuable soils, and can be used as a test area for modeling land use-based adaptation measures to climate change. The calibration and validation using the SUFI-2 algorithm in the SWAT CUP program was carried out in order to determine the water balance. After obtaining satisfactory results, the SWAT-CUP program simulated the best parameter values for climate change projections. In analyzed climate projections, the monthly mean sums of actual evapotranspiration and potential evapotranspiration will be higher compared to the simulation period of the 2010–2017 model. The exception is the month of June, where actual evapotranspiration in most climate projections is lower compared to the years 2010–2017. The average monthly total runoff for the Bystra River basin will be lower in most of the 2021–2030 climate change projections for most months compared to the reference period. Also, in the 2031–2040 and 2041–2050 periods, the average monthly total runoff will be lower for the RCP 4.5 scenarios (except for one RCP 4.5 scenario in 2031–2040). Additionally, in the case of the RCP 8.5 for the two scenarios in 2041–2050, the average monthly total runoff will be higher compared to the reference years. We determine that the analysis impact of climate change will result in 31 recognized and different small sub-catchments of the Bystra River, which result from higher precipitation and less evapotranspiration for RCP 8.5 in 2041–2050. All of the above changes in the individual components of the water balance may have a negative impact on the vegetation in the coming decades. The temperature increase and the variable amount of precipitation in individual months may lead to an increased number of extreme phenomena. Increased mean monthly sum of actual and potential evapotranspiration, as well as changes in monthly sums of total runoff, may disturb the vegetation in the studied area at every stage of growth. The above components may also influence changes in the amount of water in the soil (especially during the growing season). Counteracting the effects of future climate change requires various adaptation measures.

The hydrological assessment of the Vistula River basin in the near future will be a key element in the development of strategies to adapt agriculture to climate change. The Vistula River basin covers 61% of Poland’s area (190,062 km²) and is mainly used for agricultural production. The aim of this study is to assess the water balance of the Vistula River basin from the perspective of 2050 based on the analysis of two climate scenarios, RCP 4.5 and RCP 8.5, and the three climate models ICHEC-EC-EARTH_KNMI-RACMO22E (A), ICHEC-EC-EARTH_DMI-HIRHAM5 (B), and ICHEC-EC-EARTH_SMHI-RCA4 (C). This paper presents the steps in the development of the SWAT model and the results of the hydrological analysis of the Vistula catchment. Calibration and validation of the model were carried out using the SUFI-2 algorithm in the SWAT-CUP programme for 2013–2018. The data used to calibrate the SWAT model are monthly flow measurements [m³/s] from the measurement station in Tczew, located near the estuary of the Vistula basin to the Baltic Sea. The summary result of the work is the results of modelling the flow of the Vistula River catchment for different climate scenarios in the 2020–2050 perspective. The average annual precipitation for all projections in 2021–2030, 2031–2040, and 2041–2050 will be higher by up to 22% (763 mm) (RCP 8.5.C for 2041–2050) compared to the 2013–2018 simulation years (624 mm). The average annual temperature for most climate projections for 2021–2030 will fall to as low as 8.7 °C (RCP 4.5.B) compared to the 2013–2018 simulation period (9.2 °C). In contrast, for all projections in 2031–2040 and 2041–2050, the average annual temperature will increase to as much as 10.3 °C (RCP 8.5.C). The simulation results for the climate projections (2020–2050) indicate that there are no clear trends of change in the water management of the Vistula River basin for the coming decades. According to scenarios RCP 4.5.A, RCP 8.5.A, and RCP 8.5.B, the annual sums of potential evapotranspiration show a slight downward trend. On the other hand, for the RCP 8.5.C and RCP 4.5.C projections and the climate change scenario RCP 4.5.B, the results obtained show a slight upward trend in the annual sum of potential evapotranspiration. For the overall evapotranspiration and potential evapotranspiration assessment for all climate projections analysed, the annual evapotranspiration total shows a clear increase compared to the 2013–2018 baseline period. The average annual actual evapotranspiration for all projections in 2021–2030, 2031–2040, and 2041–2050 will increase up to 467 mm (RCP 4.5.A—2021–2030) compared to the 2013–2018 simulation period of 401 mm. The average annual potential evapotranspiration for all projections in 2021–2030, 2031–2040, and 2041–2050 will increase up to 755 mm (RCP 8.5.C—2031–2040) compared to the 2013–2018 simulation period—616 mm. The analysis of the total runoff in all climate models for the RCP 4.5 scenario shows that the annual average total runoff tends to decrease. The results of the simulations carried out for the RCP 8.5 scenario, which are generally characterised by an increase in total runoff in subsequent years, are different. When analysing annual total runoff on a regional basis, it appears that for most of the climate projections analysed (except for the RCP 8.5.A scenario), annual runoff will be lower, especially in the lowlands in the central part of the Vistula basin. In regions where the increase in precipitation is greatest in the north-western and southern basins, higher total runoff should be expected. The analysis of the total runoff in all climate models for the RCP 4.5 scenario shows that the annual average total runoff tends to decrease. The results of the simulations carried out for the RCP 8.5 scenario, which are generally characterised by an increase in total runoff in subsequent years, are different. When analysing annual total runoff on a regional basis, it appears that for most of the climate projections analysed (except for the RCP 8.5.A scenario), annual runoff will be lower, especially in the lowlands in the central part of the Vistula basin. In regions where the increase in precipitation is greatest in the north-western and southern basins, higher total runoff should be expected.

The article presents predicted changes in soil water content in the Bystra river catchment (eastern Poland) for various scenarios of climate change and adaptation practices obtained on the basis of a SWAT model simulation for three regional climate models driven by the global climate model EC-EARTH for the years 2041–2050 and the RCP 4.5 and 8.5 RCP scenarios. Climate scenarios were put against five adaptation scenarios presenting changes in land use and protective measures compared against a zero scenario of BaU (Business as Usual) kept in the future climate. Adaptation scenarios 1–5 are modifications of Scenario 0 (S-0). The 0–5 scenarios’ analysis was based on comparing soil water content and total runoff, sediment yield, actual evapotranspiration. The first adaptation scenario (AS-1) assumes an increase in afforestation on soils from the agricultural suitability complex of soil 6–8 (semi-dry, permanent dry, semi-wet). The second adaptation scenario (AS-2) assumes the creation of a forested buffer for the Bystra River and its tributaries. The third adaptation scenario (AS-3) shows one of the erosion prevention practices, the so-called filter strips. The fourth adaptation scenario (AS-4) assumes the reduction in plowing on arable land. The fifth adaptation scenario (AS-5) involves increasing soil organic carbon to 2%. Simulations revealed that each of the adaptation scenarios 1, 2, 3, 5 does not generally contribute to increasing the water content in soil on BARL (spring crops), CANP (rape), WWHT (winter crops), CRDY (other crops) on arable lands (which together account for over 50% of the catchment area). However, they can contribute to the reduction in sediment yield, total runoff and changes in actual evapotranspiration. The adaptation scenario 4 (AS-4) shows a slight increase in the soil water content on Bystra catchment in the 2041–2050 perspective. Scenario 4 indicated a slight increase in total runoff and a decrease in sediment yield, which in combination with slightly higher water content reflects the protective role of plant residue mulch, lowering the evaporation from the bare soil surface during warm seasons. The no-till adaptation practice had the highest effect in positively affecting water balance at the catchment scale among the adaptation scenarios considered.

Climatic conditions are the main factor influencing the suitability of agricultural land for crop production. Therefore, the evaluation of climate change impact on crop suitability using the best possible methods and data is needed for successful agricultural climate change adaptation. This study presents the application of a multi-criteria evaluation approach to assess climate suitability for maize production in Poland, for a baseline period (BL, 1981–2010) and two future periods 2041–2070 (2050s) and 2071–2100 (2080s) under two RCP (Representative Concentration Pathways) scenarios: RCP4.5 and RCP8.5. The analyses incorporated expert knowledge using the Analytical Hierarchy Process (AHP) into the evaluation of criteria weights. The results showed that maturity and frost stress were the most limiting factors in assessing the climatic suitability of maize cultivation in Poland, with 30% and 11% of Poland classified as marginally suitable or not suitable for maize cultivation, respectively. In the future climate, the area limited by maturity and frost stress factors is projected to decrease, while the area of water stress and heat stress is projected to increase. For 2050 climate projections, water stress limitation areas occupy 7% and 8% of Poland for RCP4.5 and RCP8.5, respectively, while for 2080 projections, the same areas occupy 12% and 32% of the country, respectively. By 2080, heat stress will become a limiting factor for maize cultivation; according to our analysis, 3% of the Polish area under RCP8.5 will be marginally suitable for maize cultivation because of heat stress. The overall analyses showed that most of Poland in the BL climate is in the high suitability class (62%) and 38% is moderately suitable for maize cultivation. This situation will improves until 2050, but will worsen in the 2080s under the RCP8.5 scenario. Under RCP8.5, by the end of the century (2080s), the highly suitable area will decrease to 47% and the moderately suitable area will increase to 53%.