Drought is one of the most severe yet extreme natural phenomena affecting society, the environment and the economy. One of the types of drought we distinguish is agricultural drought. This phenomenon causes the soil to dry out, resulting in the reduction or complete destruction of crops. Agricultural drought is becoming increasingly common in Polish areas. Already, this phenomenon has been recorded in many regions, and a significant part of our country’s area is threatened by it.
Agricultural drought – definition
Agricultural drought occurs when soil moisture is insufficient to meet the water needs of plants and carry out normal agricultural management. Also known as soil drought, it is a direct consequence of prolonged atmospheric drought. The condition for the occurrence of agricultural drought is the occurrence of changes in the state of vegetation, i.e. symptoms of water stress, decline in biomass and yield limitations. Agricultural drought leads to direct losses in natural ecosystems, but primarily results in losses in agricultural and forestry production.
As defined in the Law of July 7, 2005. On crop and livestock insurance, drought means damage caused by the occurrence in any six-decade period from March 21 to September 30 of a given year of a climatic water balance below a certain value for particular species or groups of crops and soil categories.
In Poland, agricultural drought is monitored by the Institute of Cultivation, Fertilization and Soil Science – National Research Institute (IUNG-PIB). Detailed information on the Agricultural Drought Monitoring System can be found in a previous issue ofWater Matters.
Agricultural drought – latest information from the Monitoring System
Agricultural drought occurs when the calculated values of the climatic water balance (KBW) for a municipality are lower than the critical values of the climatic water balance specified in the Regulation of the Minister of Agriculture and Rural Development dated April 11, 2019. (Journal of Laws 2019, item 739) on the values of climatic water balance for specific groups and species of crops and soils.
Agricultural Drought Monitoring in Poland is conducted for the following crop groups and species: winter cereals, spring cereals, grain corn, silage corn, rapeseed and canola, potatoes, sugar beets, hops, tobacco, ground vegetables, fruit trees, fruit bushes, strawberries, legumes. According to the latest information from the Agricultural Drought Monitoring System, in the third reporting period, i.e. from April 11 to June 10, 2023, the average value of the KBW, on the basis of which the drought risk assessment is made, was negative at -110 mm. In the current six-decade period, it has decreased by 40 mm compared to the previous period (April 1-May 31).
It is worth noting that the water deficit for crops continues to increase and is occurring throughout the country. The greatest shortages were recorded in the Mazurian and Pomeranian Lake Districts and the Kuyavia region: from -180 to -209 mm. A large water deficit also occurred in Central Poland: from -150 to -179 mm. Slightly smaller, from -50 to -149 mm, occurred in areas south of the above-mentioned areas. During the third reporting period, agricultural drought was found to have occurred over almost the entire territory of Poland as a result of prevailing moisture conditions.
The phenomenon of agricultural drought was recorded in 14 provinces. Losses caused by it were not observed only in the provinces of Małopolska and Podkarpackie. The greatest extent of the agricultural drought affected spring cereal crops. Drought in these crops was recorded in 1,468 municipalities (59.27% of Poland’s municipalities). There are also losses in the following crops: winter cereals, strawberries, fruit bushes, fruit trees, rapeseed and canola. Detailed information on current agricultural drought threats can be found on the IUNG-PIB website.