Sequestro de carbono florestal para diferentes técnicas de restauração ecológica na Caatinga

Abstract

Ecological restoration plays a crucial role in overcoming the urgent challenges related to ecosystem degradation, biodiversity loss and climate change. As a solution to the degraded environment of the Caatinga, ecological restoration seeks to recover ecosystem services, such as carbon capture from the atmosphere, and can also be an ally as a technique to promote carbon sequestration in degraded areas, strengthening the potential for climate change mitigation. This study seeks to identify effective restoration techniques and assess their impact on carbon accumulation, tree species development and seedling characteristics, with the aim of optimizing biomass production in semi-arid ecosystems. The research involved six tree species native to the Caatinga and implemented five planting treatments in 12m x 8m plots with 2m spacing, replicated five times. These treatments included the control (no manipulation), irrigation, litter transplanting, a combination of irrigation and litter transplanting, and agroforestry. The seedlings were categorized based on the dimensions of the roots (small or large) and the aerial part (small or large), and measurements of height, diameter at ground height, aerial biomass and water content of the plants were recorded three years after restoration, at the end of the experiment. Our results revealed that the addition of water had a significant impact on carbon accumulation. Jurema preta (Mimosa tenuiflora) proved to be the most promising species for greenhouse gas neutralization projects, accumulating approximately 0.09 kg of carbon per m2. The research also looked at the importance of the size of the seedlings, indicating that plants with larger roots and aerial parts accumulated more biomass and had a higher survival rate. In addition, the Catingueira species showed excellent survival in water-restricted treatments, especially when the seedlings had small roots. The total carbon accumulated at the end of the experiment was 0.1 kg per m2. These findings offer guidelines and strategies for management and restoration, highlighting the importance of taking into account not only the availability of water, but also the particularities of the species and the size of the seedlings in order to maximize the effectiveness of restoration projects in the Caatinga.