Diego Lang Burak

Pasture degradation is a global environmental problem, severely impacts soil quality, reducing efficiency of nutrient cycles, intensifying soil erosion and CO ₂ emissions, and reducing overall soil biodiversity. Scarabaeinae dung beetles are particularly affected by the fact that they play a crucial role in ecosystem balance and nutrient cycling. This study evaluated the physical, chemical, and biological soil attributes, alongside the diversity and ecological functions of dung beetles, across pasture areas with two levels of degradation in the Atlantic Forest biome, Brazil. The work was carried out in 21 sample plots: 7 within native forest fragments (FF), 7 within low-degraded pastures (LDP), and 7 within high-degraded pastures (HDP). It was quantified carbon dioxide (CO ₂ ) emissions, soil resistance to physical penetration, soil temperature, soil moisture, and carbon pools (total organic, labile, and recalcitrant C). Additionally, it was measured in dung beetle species richness, abundance, and their functional contributions to feces burial and soil excavation. Pasture degradation reduced environmental complexity, resulting in negative impacts on soil quality and beetle populations. Compared to FF areas, pastures exhibited reductions in total organic C (− 39%), labile C (− 36%), recalcitrant C (− 47%), and CO ₂ emissions (− 38%), accompanied by increases in soil resistance to physical penetration (+ 34%) and soil temperature (+ 7%). Overall, pasture areas had a 55% reduction in beetle abundance and a 49% reduction in species richness compared to FF areas. Notably, LDP area maintained twice the abundance and diversity of dung beetles compared to HDP, where roller populations and feces burial activity were significantly reduced. Implications for insect conservation: Land management strategies must be improved in agricultural landscapes of the Atlantic Forest to mitigate pasture degradation, increasing soil quality. Restoring and maintaining lower levels of pasture degradation is vital for preserving dung beetle diversity, which in turn safeguards critical ecosystem services such as organic C incorporation and soil nutrient cycling.

The processing of dimension stones for the construction sector involves transforming rock blocks into slabs via sawing and polishing. This process generates a fine-grained waste composed largely of rock powder derived from the processed rock. Several studies indicate that the rock powder produced as a processing waste can release Ca, Mg, and K. However, alongside the release of macronutrients, there is the possibility of releasing undesirable constituents, such as Na, which is also a component of the minerals forming silicate rocks. This study aimed to analyze the risk of salinization that these materials may cause to soil if applied without a thorough evaluation of their composition. Samples were analyzed in terms of physical, chemical, and mineralogical parameters; exchangeable inorganic constituents; percentage of exchangeable sodium; and sodium adsorption ratio. The data indicate that residues stored in landfills in a random and unsorted manner do not fully meet the criteria established by Brazilian regulations for soil remineralizers. However, their characteristics suggest good potential for use in the agricultural sector, although this would require blending with other agricultural inputs and/or segregating residues from certain types of rocks to comply with current regulations.

The processing of dimension stones for the construction sector involves transforming rock blocks into slabs via sawing and polishing. This process generates a fine-grained waste composed largely of rock powder derived from the processed rock. Several studies indicate that the rock powder produced as a processing waste can release Ca, Mg, and K. However, alongside the release of macronutrients, there is the possibility of releasing undesirable constituents, such as Na, which is also a component of the min-erals forming silicate rocks. This study aimed to analyze the risk of salinization that these materials may cause to soil if applied without a thorough evaluation of their composition. Samples were analyzed in terms of physical, chemical, and mineralogical parameters; exchangeable inorganic constituents; percentage of exchangeable sodium; and sodium adsorption ratio. The data indicate that residues stored in landfills in a random and unsorted manner do not fully meet the criteria established by Brazilian regulations for soil remineralizers. However, their characteristics suggest good poten-tial for use in the agricultural sector, although this would require blending with other agricultural inputs and/or segregating residues from certain types of rocks to comply with current regulations.

Na indústria de rochas ornamentais, os resíduos gerados em forma de fragmentos e lodo, ao entrarem em contato com a água, podem aumentar a concentração de íons dissolvidos devido à solubilização de algumas substâncias químicas, o que pode afetar a produção agrícola. A Razão de Adsorção de Sódio (RAS) é um importante parâmetro utilizado para avaliar a qualidade da água de irrigação e, em conjunto com a condutividade elétrica (CE), serve como indicador do risco de salinização do solo. Este estudo avaliou o efeito da salinidade do extrato solubilizado de rejeitos de três tipos de rochas ornamentais, com diferentes granulometrias, na taxa de infiltração do solo. Foram testados rejeitos de quartzo sienito, gabro-norito e gabro, coletando tanto rejeitos grossos de pedreira quanto finos, originados pelo corte de blocos em teares multifios. As amostras foram secas, homogeneizadas e submetidas ao ensaio de solubilidade com água ultrapura. O extrato resultante foi analisado quanto ao pH, condutividade elétrica, Razão de Adsorção de Sódio (RAS) e outros parâmetros, conforme a norma NBR 10004:2004. Os resultados mostraram que a CE foi mais alta nos resíduos finos, porém, nenhum extrato apresentou restrições quanto à salinidade. Quanto à RAS, os resíduos finos apresentaram restrições moderadas, enquanto os demais mostraram restrições severas. Esses resultados indicam que, quando aplicados em excesso ou de forma cumulativa, esses resíduos podem afetar a infiltração de água no solo, o que pode prejudicar as condições agrícolas. Palavras-chave: Agrominerais. Fertilização. Rochagem. Teste de Solubilização.

Soil chemical analysis is a fundamental to achieve optimal cultivation conditions in a productive silvopastoral system, essential for the planning and management of this activity. The objective of this research is to map the spatial distribution of nutrients in the soil in a 5-year-old silvopastoral system composed of brachiaria-brizantha and jacarandá-da-bahia, and to analyze the effect of tree density and canopy on nutrient levels. The study was conducted at the experimental area of the Capixaba Institute for Research, Technical Assistance, and Rural Extension (INCAPER) in the district of Pacotuba, ES. The delimitation of the work area was done using geographic information systems, to create a regular grid of points to enable systematic soil sampling. A total of 75 disturbed soil samples were collected at depths of 0-0.10 m to obtain quantitative soil nutrient data. High-quality images obtained using a remotely piloted aircraft (RPA) allowed for the overlay of soil nutrient data, pasture data, forest inventory data, and sample plot data to assist in comparative analyses. This enabled identification of the areas with lower canopy development, particularly in the northeast portion. By cross-referencing the spatialized soil nutrient data with the data obtained through RPA, it was possible to correlate them with the lower or higher development of the system. The use of RPA, together with a georeferenced database, proved to be an innovative and powerful tool to support decision-making, allowing for the monitoring of system evolution and serving as a basis for evaluating the relationship between chemical elements and tree canopies.

Bovine enzootic hematuria (BEH) is a clinical form of poisoning in cattle caused by the consumption of Pteridium spp. (bracken fern), which has no treatment. However, selenium (Se) and vitamin E supplementation are feasible. The aim of this study was to evaluate the effects of supplementation with increasing doses of selenium associated with vitamin E in cattle with BEH, compare the levels of Se in whole blood and blood serum, and evaluate the activity of glutathione peroxidase, total antioxidants, and the relative activity of the enzyme monoamine oxidase (MAO). Four groups of cattle with BEH were supplemented parenterally for 13 weeks with increasing doses of Se: Control group, Treatment group 1 (0.05mg/kg), Treatment group 2 (0.1mg/kg), and Treatment group 3 (0.2mg/kg). All groups received 500mg of vitamin E in combination with the Se supplementation. The measured variables included weight, hematuria intensity, hematocrit, total plasma protein, plasma fibrinogen, blood glutathione peroxidase activity, and total antioxidant levels. The blood concentrations of Se and relative MAO activity were evaluated every two weeks. Kruskal-Wallis and Friedman tests (P0.05) between the treatments, but there was a significant difference over time (PP0.05). For glutathione peroxidase, there was no significant difference (P>0.05) among the treatments, but there was a significant difference (P0.05). Selenium levels were higher in Treatment group 1, reaching the highest concentration (235.3µg/L) in the blood serum at eight weeks. Therefore, supplementation with Se at a dose of 0.05mg/kg associated with vitamin E improved the clinical condition of hematuria but did not interfere with glutathione peroxidase activity or with levels of total antioxidants. MAO activity was reduced by vitamin E supplementation. These results indicate that the serum is the best site for measuring Se levels.

Biochar shows important characteristics required for the substrate, acting as a conditioner and improving soil properties. This study aimed to evaluate the effects of adding different proportions of eucalyptus bark biochar to the substrate, produced at different pyrolysis temperatures, on the quality of Eucalyptus grandis seedlings. The treatments were distributed in a randomized block design in a 4 x 4 + 1 factorial scheme: four pyrolysis temperatures of the biochar (250, 350, 450, and 600 °C), four proportions of biochar (2.5, 5, 10, and 15% of the tube volume) and a control (no biochar), added to a substrate made up of 80% coconut fiber and 20% vermiculite. The substrate was chemically characterized and the seedlings were evaluated after 90 days in terms of neck diameter, height, aerial and root phytomass, Dickson quality index, and classified in terms of root system quality. The composition of the substrate provided optimum root development for the seedlings. In the treatments with higher pyrolysis temperatures and proportions of biochar, there was a reduction in the availability of phosphorus, and an increase in pH and Na levels, which are not recommended for the substrates in treatments T13, T16, and T17.