Técnicas de recuperação florestal em áreas perturbadas na caatinga, Ceará

Abstract

The unsustainable use of natural resources in semi-arid regions have become their forests, one of the most threatened among the forest formations tropical dry in the world. Thus, actions aimed at the recovery of the Caatinga are of great interest in the conservation of these areas, yet little known. In this context, the objective of this work was to verify the potential of different techniques of rehabilitation and development of seedlings in different soil types, in disturbed areas in Caatinga. The research was conducted on Farms Triunfo-Ibaretama and Não Me Deixes (NMD) and Quixadá, both in Ceará. Were installed three experiments: nucleation with poles (artificial and natural), where artificial poles were installed in two farms, being one with around disturbed (Farms Triunfo) and the other with surroundings kept (Farms NMD) and natural poles of carnaúba (Copernicia prunifera) assessed in Farms Triunfo; The planting of seedlings in three soil types (plansol, vertisol and neosol) with six native species (coronha - Vachellia farnesiana, ingá bravo - Lonchocarpus sericeus, mutamba - Guazuma ulmifolia, sabonete - Sapindus saponaria, sabiá - Mimosa caesalpiniifolia and trapiá - Crataeva tapia), With and without the use of hydrogel; and the planting of seedlings under the effect of the use of carnauba straw in the vertisol hidromórfico saline sodic with three species ( coronha - Vachelia farnesiana, sabiá - Mimosa caesalpiniifolia and marizeira - Geoffroea spinosa). In the experiment with poles, on condition of surroundings kept, was dispersed greater quantity of seeds (10.306) and with greater diversity of species, however, it is possible to observe a greater diversity of tree species regeneration under the canopy of natural poles of nature carnauba. The poles exercised the function nucleadora, incrementing the seed rain zoochoric and recruitment of the species. In the experiment with planting seedlings in different soils the survival was 87.5% in the planosol, 84.72% in June and only 3% in the vertisol. The school had 100% survival in planosol and neosol, and reached the highest (198.9 cm), followed by the butt (182 cm) and mutamba (134.95 cm). The species tested showed to be promising in recovery in areas of Caatinga. In the experiment with planting seedlings under the use of carnauba straw, the treatments with carnauba inside the pit and the control were those who had worse outcomes, having 19.44% and 33.33% survival, respectively. The butt had the best survival rates, maintaining the treatment with carnauba on the pit 95.3% of the seedlings alive. The use of carnauba straw has favored the survival and growth of the species tested when applied over the pit of seedlings, even when used inside the burrows was, in general, harmful to the survival and development of the seedlings. It can be concluded that the technique nucleadora with use of artificial poles is promising in the recovery of areas in caatinga and the techniques of recovery with the use of planting seedlings, presents a potential variable according to the type of soil of the area and the species used, and may also be favored or hampered by the use of conditioner of soil. The use of mulch in the planting of native species in the Vertisol, proved to be promising in the recovery of areas in Caatinga.