Ecophysiological responses of bromelias in the restinga in simulated climate change scenarios

We investigated the ecophysiological responses of the bromeliads Aechmea nudicaulis and Vriesea procera, seeking to assess their suitability to survive in a climate change scenario (optimistic scenario RCP 2.6 of the IPCC, 2021) in a Restinga environment. To carry out this investigation, we used open-top chambers (OTC). During a period of nine months (June 2022 to February 2023), the bromeliads A. nudicaulis and V. procera were subjected to the following treatments: treatment T: plants transplanted to the environmental conditions of the bare sand of the restinga and subjected to the microclimatic conditions of the OTC's; control C: plants transplanted to the environmental conditions of the bare sand of the restinga. The ecophysiological variables height, rosette diameter, relative water content, specific leaf area and total weight of the plants were evaluated. In addition, dead plants were counted. The OTC's showed an average increase in temperature and VPD (Vapor Pressure Deficit) of 1.6°C and 0.5 Kpa, respectively, and an average reduction in RH (relative humidity) of 5.3%. The results of this study indicated that the increase in local temperature that occurred between the sixth and seventh months evaluated (November and December) created limiting conditions that exceeded the tolerance capacity of the bromeliads studied. Furthermore, the climatic conditions of the OTCs intensified the damage that occurred in the plants, verified here by the reductions in the values ​​of the ecophysiological attributes evaluated in the bromeliads studied. In addition, the high mortality rate (above 50%) reinforces the idea that the climatic conditions of the OTC's induced the bromeliads studied to a senescence process. Therefore, these results are important, as they indicate that even the most optimistic climate change scenario (IPCC 2021 RCP 2.6) can harm the growth and development of these bromeliads, which are essential for the structure and functioning of Restinga communities.