Irrigation in Agriculture – Needs, Possibilities and Threats to the Environment in the Face of Progressing Climate Change

Purpose: This article presents an analysis of the structure of water shortages in cultivation of major agricultural crops, and the possibility of using groundwater resources for their irrigation. Design/Methodology/Approach: The study was conducted in north-eastern Poland, in the Warmińsko-Mazurskie Voivodeship, which is an area properly representing the conditions prevalent in Central and Eastern Europe. Our analysis of the climatic conditions in this region recorded between 1981 and 2020 demonstrated the stability of precipitations and steadily increasing air temperature, which rose by 1.7 oC in that period (an increase of 0.04 oC year-1). Findings: The study proves that areas most abundant in groundwater are situated in the southern and central parts of the Warmińsko-Mazurskie Voivodeship. Water shortages are particularly harmful to root crops, such as sugar beets and potatoes, while cereals and oilseed rape are less sensitive. Assuming that the average yield of a potential drilled well is 45 m3 h-1, one well can irrigate an area of 27 to 67 ha if cropped with root vegetables, and from 4 to 44 ha under cereals. It has been demonstrated that under drought conditions (occurring no often than once every five years), as many as 6,399 wells tapped into the main usable groundwater aquifer would be needed to offset the water shortages. This figure illustrates the size of the demand for water and the limited possibility of renewing groundwater supplies if droughts were to appear frequently. Some threats to agricultural ecosystems and the environment are also identified, and therefore other sources of water for agriculture need to be looked for, e.g. retention and redistribution of atmospheric precipitations, rational use of surface waters, desalination of water, or recovery of polluted waters. Practical Implications: Climate change, associated with a growth in air temperature and elevated evapotranspiration, entails greater demand of plants for water. In agriculture, out of the concern for good volumes and quality of yields and food security, there is ongoing search for technologies that will supplement water shortages. Originality/Value: Studies on the use of groundwater for irrigation of crops should take into account the supply of water resources, estimated groundwater consumption and replenishment, as well as threats to the natural environment and other water users due to excessive exploitation of these water resources.