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Brazilian mahogany, cutter ant, Nutrient cycling.
In order to study the nutrient cycling, as well as the spatial distribution of the cutting ant Atta laevigata and to know the contribution of this species in the soil fertility associated to the Brazilian mahogany, it is intended to answer the following questions: What is the contribution of the Brazilian mahogany litter in ecosystems forestry How is the spatial distribution of the Ata laevigata in different forest ecosystems with Brazilian mahogany? What are the contributions of leaf-cutting ants to soil fertility? The hypotheses were elaborated for the questions: The litter produced in the cultivated ecosystems of Brazilian mahogany contributes to the enrichment of the soil because they produce organic matter and chemical elements. The spatial distribution of the herbal Atta laevigata is aggregated. Cutting ants of the species Atta laevigata contribute to the increase of macronutrients and organic matter in Brazilian mahogany ecosystems. This research was divided into three chapters, where the first one sought to verify the importance of Atta laevigata for nutrient cycling and soil fertility; the second was to analyze the availability and concentration of nutrients such as C, N, P, K, Ca, Mg and litter organic matter in different mahogany forest ecosystems and the third was to characterize the spatial distribution of Atta laevigata in mahogany plantations using geostatistical analysis. This research took place during two years in forest plantations belonging to the Tramontina Company, located in the municipality of Aurora do Pará-PA, eastern Amazonia. Ecosystem 1 was characterized by a consortium of Brazilian mahogany with other meliaceae, such as Australian cedar (Toona ciliata), African mahogany ( Khaya ivorensis) and neem (Azadiractha indica). Ecosystem 2 characterized by mahogany monoculture and Ecosystem 3 characterized by mahogany enriched forest. Pitfall traps were used to collect the cutting ants, which were installed 80 traps / forest ecosystem, spacing 10 m equidistant between pitfalls. To collect the litter, four plots of 50 mx 50 m were installed in each treatment, where each plot contained two collectors with 1 m opening, systematically distributed every 15 m (between plants) and suspended at 0,15 m soil level, totaling eight collectors per treatment and also to collect litter accumulated on the ground was used a metal jig with collection area of 0.625 m², with eight collections per treatment.