RESUMO
As lithium (Li) stands out as a crucial component of batteries, the inappropriate disposal of electronic gadgets might drive Li pollution in environmentally sensitive environments, such as dumps, where castor bean (Ricinus communis) plant communities are usually found. The exposure to high Li concentration is potentially harmful to the environment and humans. Therefore, it is opportune to evaluate the potential of bioindicator species to monitor Li contamination. In this scenario, the present study assessed the effects of Li exposure on the development of castor bean plants exposed to lithium chloride at five Li dosages (0, 5, 10, 20, and 30 mg dm-3). Significant symptoms of phytotoxicity were observed at all doses. Li dosage exhibited increasing impairment effects on plant biometrics, such as stem diameter and the number of leaves, as well as on the SPAD index, nutritional balance, and biomass production. Our findings suggest castor bean as a potential model species for biomonitoring Li-contaminated areas.
Assuntos
Lítio , Ricinus communis , Ricinus communis/efeitos dos fármacos , Lítio/toxicidade , Monitoramento Ambiental/métodos , Ricinus/efeitos dos fármacos , Poluentes do Solo/toxicidadeRESUMO
O objetivo deste trabalho foi avaliar a concentração de nitrogênio em plantas de milho e ao longo do perfil de um Latossolo Vermelho eutroférrico submetido a doses de lodo de esgoto e fertilizante mineral. O experimento foi instalado em delineamento experimental em blocos casualizados com 4 tratamentos (0,0; 55,0; 110,0 e 167,5 Mg.ha-1 de lodo de esgoto em doses acumuladas) e 5 repetições para um período de avaliação de 1 ano. A amostragem de solo foi realizada aos 60 dias após a emergência (d.a.e.) das plantas nas profundidades 0,0-0,1, 0,1-0,2, 0,2-0,4, 0,4-0,6, 0,6-0,8 e 0,8-1,0 m. Também aos 60, 80 e 128 d.a.e. foram coletadas, respectivamente, folha diagnose, planta inteira e grão. As maiores doses de lodo de esgoto proporcionaram maiores quantidades de nitrogênio no solo. O nitrogênio do solo, após a profundidade de 0,6 m, não diferiu entre as camadas avaliadas. Quanto maior a dose de lodo de esgoto, menor a proporção de nitrogênio em profundidade.
The aim of this study was to evaluate the concentration of nitrogen in corn plants and along the profile of an Oxisol subjected to doses of sewage sludge and mineral fertilizer. The experiment was conducted in randomized complete block design with 4 treatments (0.0; 55.0; 110.0 and 167.5 Mg.ha-1 of sewage sludge accumulated doses) and 5 reps for a trial period of 1 year. Soil sampling was performed 60 days after emergence (d.a.e.) plants at depths 0-0.1, 0.1-0.2, 0.2-0.4, 0.4-0.6, 0.6-0.8 and 0.8-1.0 m. Also at 60, 80 and 128 d.a.e. were collected, respectively, diagnosis leaf, whole plant and grain. Higher doses of sewage sludge provided higher amounts of nitrogen in the soil. The soil nitrogen, after the depth of 0.6 m, did not differ between the layers evaluated. The higher the dose of sewage sludge, the lower the proportion of nitrogen in depth.