Conhecendo a influência das mudanças climáticas na produção de forrageiras

Abstract

Climate change directly impacts the planet’s fauna and flora. Alterations in temperature patterns, precipitation, water availability, and CO2 concentration can lead to significant changes in agriculture. Plants with C3 and C4 photosynthetic metabolisms tend to respond differently to shifts in environmental factors. Therefore, selecting species that are best suited to the abiotic conditions of a specific region is crucial for achieving high productivity. For forage production, the scenario is no different. C3 forage species are generally better adapted to temperate climates, whereas C4 species thrive in tropical conditions. In light of this, the study aimed to analyze ongoing research on the influence of climate change on forage plant production and evaluate the impacts of climate change—particularly in terms of average temperature, precipitation, water availability, and CO2 concentration—on the productivity of C3 and C4 forage species. A literature review was conducted using databases such as Google Scholar, Scopus, SciELO, BASE, and BDTD. Keywords included "climate change," "forage," "pasture production," "climate impacts," as well as their equivalents in Portuguese. The factors most affecting forage production—water availability, temperature, and CO2 concentration—were tabulated, converted into nominal and percentage values, and subjected to exploratory and descriptive data analysis. A decision tree analysis was then performed using statistical packages in the R software. For both C3 and C4 plants, the factor “water,” whether in reduced precipitation or decreased availability, led to a reduction in dry matter production by up to 25% and in net primary productivity (NPP) by up to 11%. Conversely, increased temperature and CO2 concentration, either independently or simultaneously, resulted in gains in dry matter production of up to 119% and 42%, respectively. Thus, considering projected climate changes over the coming decades, reduced precipitation and water availability are expected to decrease forage productivity. Meanwhile, rising average temperatures and CO2 concentration are likely to enhance productivity.