Climate change has been a central theme in public and economic policies worldwide, as scenarios of increased atmospheric carbon dioxide (CO2) concentration, rising air temperatures, and changes in rainfall totals and distribution are being drawn up. In the Amazon, in addition to concerns about the biome as a whole, questions arise regarding species that are particularly important for the regional economy. This is the case, for example, with Jaborandi (Pilocarpus microphyllus) due to being a natural source of alkaloids used industrially in medication production, and also with Açaí (Euterpe oleracea) due to the widespread use of its fruit, especially in the food industry.

In light of this, doctoral student Genilda Canuto Amaral conducted two studies with seedlings of both species in controlled environments, using climate-controlled greenhouses and open-top chambers for injecting carbon dioxide into the atmosphere. In the first study, the effect of different climatic conditions and soil moisture levels on the ecophysiological processes of jaborandi seedlings was evaluated. In the second study, the effect of climate change on the ecophysiology of jaborandi and açaí seedlings was assessed by simulating three climate scenarios: current Amazon, RCP4.5, and RCP8.5.

In the first study, the results revealed that different temperature regimes and soil moisture levels affected the growth of jaborandi seedlings. In cooler environments, there was a reduction in quantum yield, an increase in minimum fluorescence and enzymatic activity, limiting physiological processes and reducing growth, effects also caused by water stress. Thus, the results allowed the conclusion that seedlings grown in warmer and well-irrigated environments showed better growth and dry matter production. This type of work serves as an interesting indicator for commercial exploitation projects of the species, especially in other regions.

In the climate change scenarios, the second study showed that the ecophysiology of both species was significantly affected by future climates. For both species, the results showed that the conditions of the RCP4.5 and RCP8.5 climate scenarios limited physiological processes and that water stress inhibited seedling ecophysiology regardless of the scenario. The combined effect of increased CO2 concentration with rising air temperature and vapor pressure deficit limited leaf water potential, fluorescence parameters, and enzymatic activity. In açaí seedlings, gas exchange revealed a beneficial effect generated by increased CO2 concentration on leaf net photosynthesis, but the elevation of atmospheric demand limited water status and fluorescence parameters, resulting in reduced growth in future scenarios. Despite being developed under controlled conditions, the study signals negative impacts on two important Amazonian species.