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Aluminum composite material (ACM) is associated with a high consumption of natural resources, and its production consumes high energy levels and a considerable volume of waste. Given this consequence, alternative solutions for ACM waste are necessary. This work evaluates the chemical, structural, microstructural, and mechanical characteristics of incorporating ACM board waste in producing plaster mortars. The results of the chemical XRF data revealed high concentrations of the calcium system in the ACM mortars. In addition, the XRF analyses showed that the incorporation of ACM affects the homogeneity of the material composition. XRD data showed crystalline phases of Quartz (SiO₂), Portlandite (Ca(OH)₂), Calcinite (CaCO₃), and Ettringite (Et. Ca₆Al₂(SO₄)₃ (OH)₁₂.₂₆H₂O), which were also verified from SEM experiments. In addition, mortars ACM5 and ACM10 presented similar %C concentrations. It was evident that high levels of ACM incorporation substantially increased the %C on the material's surface. These %C concentrations on the surface of the mortars evidence the presence of the polymeric material ACM on the surface of the mortars. Low concentrations of %Si and %Ca on the surfaces of ACM20 and ACM25 also revealed a low presence of SiO2 and calcium systems (Portlandite and CSH). Considering high levels of ACM incorporation in mortars and observing the results, the ACM residue acts as a polymeric coating on the material's surface.

This research evaluated soil properties in a silvopastoral system using double rows of tree legumes. Treatments were signalgrass (Brachiaria decumbens) in monoculture or in consortium with sabiá (Mimosa caesalpiniifolia) or gliricidia (Gliricidia sepium). Treatments were arranged in a complete randomized block design, with 4 replications. Response variables included chemical characteristics and physical attributes of the soil. Silvopastoral systems had greater (P3) than signalgrass monoculture (2.0 mmolc/dm3). Water infiltration rate was greater within the tree legume double rows (366 mm/h) than in signalgrass (162 mm/h) (P = 0.02). However, soil moisture was greater in signalgrass pastures (15.9%) (P = 0.0020) than in silvopastures (14.9 and 14.8%), where soil moisture levels increased as distance from the tree rows increased. Conversely, the light fraction of soil organic matter was greater within the tree legume double rows than in the grassed area (P = 0.0019). Long-term studies are needed to determine if these benefits accumulate further and the productivity benefits which result.