ABSTRACT Mining activities generally affect soil quality, degrading it and creating the need for consistent environmental recovery efforts. This study evaluates the influence of monospecific and mixed stands of Sesbania virgata (S) and Eucalyptus camaldulensis (E) on the chemical properties and microbial activity of the soil in a degraded area by clay extraction in the northern part of the state of Rio de Janeiro, Brazil. Four treatments (100S:100 % Sesbania , 100E: 00 % Eucalyptus , 50S:50E: 50 % Sesbania + 50 % Eucalyptus , and DASV: a degraded area with spontaneous vegetation) were established according to a randomized complete block design with three replicates. Samples were collected in the 0.00-0.10 m layer in the rainy season (March) and the dry season (September). The properties evaluated were pH in water; contents of P, K + , Ca 2+ , Mg 2+ , Al 3+ , H+Al, N, and C; C/N ratio; total microbial activity (soil respiration - CO 2 emission); and total enzymatic activity (fluorescein diacetate hydrolysis). The reforestation of degraded areas by clay mining with the species S. virgata and E. camaldulensis either in monospecific or mixed stands increased the nutrient contents, C levels, and total microbial activity in the soil. It was possible to separate the planting systems (100S, 100E, 50S:50E) and the DASV using principal component analysis. In both seasons, soil C contents, chemical properties, and biological variables improved in the planted areas, in contrast with the DASV. The revegetation of degraded areas by mining improved the chemical and biological properties of the soil, leading to higher soil quality in revegetated areas compared to degraded areas with natural vegetation.

ABSTRACT Triadimenol is a systemic fungicide which belongs to the group of triazoles, used mainly for the control of several diseases of plants. The present work aimed to evaluate the effect of triadimenol in the culture of beans. The experimental design was completely randomized; using 6 treatments with 4 replicates and 2 pots per replicate. The treatments were: T1= 0.527g of baysiston®. (170 Kg/ha); T2= 0.124g of baysiston® (40 Kg/ha) T3= control; T4= 0.155g of baysiston® (50 Kg/ha); T5= 0.217g of baysiston (70 Kg/ha) and T6= 0.186 g of baysiston® (60 Kg/ha). For most of the characteristics evaluated the control T3 was statistically superior to other treatments. For soil microbial activity, the average hydrolysis of FDA in all treatments was 244.926 µg of FDA hydrolyzed hour-1 g-1 of soil. Although the test has been shown to be effective, no significant difference was observed between treatments.

RESUMO O triadimenol é um fungicida sistêmico, pertencente ao grupo dos triazóis, aplicado principalmente via solo no controle de diversas doenças de plantas. Esse trabalho teve como objetivo avaliar o efeito do triadimenol na cultura do feijoeiro e atividade microbiológica do solo submetido a diferentes concentrações de triadimenol. Os estudos foram realizados no laboratório de química e na casa de vegetação, instalados no CCA/Alegre/ES. O delineamento experimental adotado foi o inteiramente casualizado com 6 tratamentos, com 4 repetições utilizando 2 vasos por repetição. Os tratamentos utilizados foram: T1= 0,527 g de baysiston®. (170 Kg/ha); T2= 0,124 g de baysiston® (40 Kg/ha) T3=testemunha; T4= 0,155 g de baysiston® (50 Kg/ha); T5= 0,217 g de baysiston (70 Kg/ha); T6= 0,186 g de baysiston® (60 Kg/ha). Para maioria das características avaliadas o tratamento T3 foi estatisticamente superior aos demais tratamentos. Para a atividade microbiológica do solo, a hidrólise de FDA ocorreu em todos os tratamentos com média 244,926 µg FDA hidrolisada hora-1 g-1 de solo, mas não houve diferença significativa entre nenhum dos tratamentos.