Espécies de cerrado: sua importância na recuperação de solosdegradados

• Autor(a) principal: Villela, Beatriz Biancardi
• Data de Publicação: 2021
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/216045
• topic: Grasses; Subsoil; Dipteryx alata; Rhizobium tropici; Stylosanthes sp.; Gramíneas; Subsolo

The suppression of vegetation and surface layers of the soil are common actions for the construction of large infrastructure works such as hydroelectric plants, which cause serious edaphic damage such as a reduction in the content of organic matter, lack of structure, porosity and aggregation of particles, making it difficult to infiltration of water and facilitating erosion. Revegetation techniques have been indicated for the recovery of vegetation cover in such compromised areas, providing nutrients through cycling resulting from the decomposition of waste generated, and promoting the incorporation of organic matter into the soil via roots and exudates, stimulating the activity of the microbiota. The symbioses and associations between plants and microorganisms are extremely important in the reestablishment of plant species, nitrogen-fixing bacteria can increase the availability of the nutrient for the plant, arbuscular mycorrhizal fungi (AMF) and dark septate endophytic fungi (DSE) provide a greater volume of explored soil and consequently greater absorption of water and nutrients, thus improving the adaptability of species in a degraded environment. Given the above, the objective of this work was to evaluate the potential of legumes, grasses and Rhizobium tropici in the recovery of sustainability of degraded soils in the Cerrado. The experiment was conducted at the Faculty of Engineering – UNESP/Campus of Ilha Solteira, under protected cultivation conditions, in soil from a degraded area (SAD) during the construction of the Ilha Solteira Hydroelectric Power Plant (HPP) in the 1960s, and another from a conserved Cerrado area (CER), both collected in the municipality of Selvíria (MS). The experimental design was completely randomized, and the species used were the legumes Dipteryx alata (Baru) and Stylosanthes spp., and the grasses (Sporobolus indicus and Aristida riparia), establishing the following treatments D. alata, D. alata + Stylosanthes spp. (D. alata + Sty), D. alata + Rhizobium tropici (D. alata + Rhi), D. alata + Grasses (D. alata + Grm) and D. alata + Sty + Grm) with 5 treatments per soil and 4 repetition. The attributes evaluated were height, diameter, leaf area index, chlorophyll, fresh and dry mass of shoots and roots, total fresh mass, total dry mass, root volume, water content in shoots and root system and total water , soil fertility, basal soil respiration, root colonization by arbuscular mycorrhizal fungi (AMF) and dark septate endophytic fungi (DSE) and images of aggregates in scanning electron microscopy. The introduction of vegetation promoted increases in P and MO contents and increased CTC in the CER soil, showing a small increase in pH and reductions in Al3+ and H+Al, the association of grasses, Stylosanthes spp. and inoculation with R. tropici contributed to the growth of D. alata in SAD soil. Scanning electron microscopy images showed the contribution of hyphae and roots to soil aggregation.