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The demand for food has intensified production in agricultural areas and stimulated the use of nanotechnology to develop new inputs, especially nanoparticle materials. In this new context, predicting the impact of using nanoparticles on non‐target organisms becomes a necessary measure. The aim of this study was to evaluate the ecotoxicological potential of magnesium (Mg2+) added via magnesium oxide nanoparticles (MgO‐NPs), magnesium oxide (MgO), and magnesium nitrate hexahydrate (Mg [NO3]2·6H2O) incubated over time in tropical soil on earthworms (Eisenia andrei), springtails (Folsomia candida), and enchytraeids (Enchytraeus crypticus). Tests were conducted using a clay‐textured Latossolo Vermelho distrófico (Oxisol), which received increasing doses of Mg2+ (0; 25; 50; 100; 200 and 400 mg kg−1 of soil) from the three sources tested added to the soil. Treated soil was incubated for 120 days in a room with controlled temperature and photoperiod, and the ecotoxicological tests were performed at 0, 60, and 120 days of incubation. Despite having caused reduction in the reproduction of F. candida at the incubation time 0, MgO‐NPs showed a low toxic potential against the other species studied, with toxicity only at a higher dose of 50 mg Mg kg−1 when compared to the other sources of Mg2+ applied to the soil (MgO and Mg [NO3]2·6H2O). Responses associated with incubation times showed that all magnesium sources tested have lower toxicity over incubation time.

A biodiversidade comumente é referenciada como a diversidade biológica e variedade de formas de vida, porém esses organismos não devem ser observados de uma forma individual, mas sim como uma estrutura complexa e funcional que interage entre si. Educar o cidadão desde cedo para conhecer a biodiversidade da sua região e então ajudar a conservá-la, preservá-la e protegê-la é um processo importantíssimo. Nosso objetivo foi analisar o conhecimento dos estudantes do último ano do Ensino Médio sobre o tema biodiversidade regional. É uma pesquisa qualitativa e quantitativa, realizada em três escolas, de três municípios distintos, com 65 estudantes. Dentre os três níveis da biodiversidade, os estudantes conhecem a diversidade de espécies. A maioria deles conceitua espécies nativas e endêmicas, mas não sabe conceituar espécies exóticas. De forma geral eles entendem que a grande importância da biodiversidade é o equilíbrio ecológico e que a perda da biodiversidade levará ao desequilíbrio ecológico. As espécies nativas, citadas com mais frequência, são espécies presentes nas áreas urbanas e os estudantes com mais contato com a natureza citam, em média, um número maior de espécies, indicando a importância de resgatar o contato com a natureza.

Predator-prey relationships are not limited to predation. A predator may release chemical cues that may directly affect the physiology and behavior of a prey by fear and intimidation. Our objective was testing the effect of the body size of predator (dragonfly larvae) on the larval development time and mortality, as also, on the survival, wing asymmetry and adult size of Ae. aegypti. Using a microcosm set-up, we simulated the predation risk by dragonflies (Odonata, Libelulidae family) over Aedes aegypti. Microcosms consisted of 40 larvae of Ae. aegypti under the indirect effect of predators with different body sizes (four treatments comprising different body size classes; n = 5 per treatment). We found that intermediate-sized predators had the highest effects on the mosquito's life history traits. Predator presence increased prey larval mortality (±150%) and accelerated development times (±33%), and reduced adult body size (± 24%) and survival (56%). On the other hand, no change in asymmetries of wings size was observed in Ae. aegypti mosquitoes. Therefore, our results support that both predator presence and size are responsible for changes in Ae. aegyptitraits during the larval and adult stages.

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