Impact of climate changes on pests in agriculture

Abstract

The occurrence, number, and dynamics of the spread of pests in agriculture are largely determined by environmental factors, primarily air and soil temperature, rainfall, length of frost-free period, and soil moisture. Climate change is undeniable and is manifested, among other things, in an increase in the temperature of land and oceans, an increase in extreme weather conditions, and an increase in the concentration of greenhouse gases, a rise in sea level, an increase in the melting of ice, and a decline in glaciers. These climate changes affect, among other things, affect on the socio-economic development, migration and displacement, terrestrial and marine ecosystems as a food production security. An increase in temperature can have an impact on accelerating the development of pests, as the sum of temperatures is reached more quickly depending on the number of days required for a particular life stage of pests to occur („number of degree-days“). This may cause the range of pests already present to expand to higher elevations and latitudes, increase the number of generations during the year, increase the number of pests, or cause them to appear earlier during the year. Changing conditions during overwintering can be a critical factor in pest population dynamics. The aim of the study was to calculate the sum of active temperatures - GDD (growing degree days) above 10°C for Banja Luka, Bijeljina, Doboj, Sokolac and Bileća for the period from 1981 to 1990 and for the period from 2012 to 2021. The sum of active temperatures was calculated using the average method. The results show that in the last decade there was a statistically significant increase in the sum of active temperatures for the monthly periods July 1, August 1, September 1, and October 1 compared to the period 1981 to 1990. This statistical significance was not observed for the period from June 1 to 30 for Bijeljina, Doboj and Sokolac and for Bileća until June 1.