Estrutura de um solo construído cultivado com diferentes espécies de poáceas

Abstract

In surface coal mining the vegetation is completely suppressed and layers of soil and rocks that cover the coal seams are removed, causing drastic changes in the original soil profile. This study aimed to evaluate the influence of different species of grasses in the recovery of a constructed soil structure as part of the strategy of reclamation for coal mining. The treatments were: T1 - Hemarthria altissima, T2 - Paspalum notatum, T3 - Cynodon dactilon, T4 - Urochloa brizantha. As a control, a bare constructed soil was used, called T5. Disturbed and undisturbed soil samples were collected in 0.00-0.10m and 0.10-0.20m layers for the determination of the percentage of macroaggregates and microaggregates, mean weight diameter, organic carbon, bulk density and macroporosity. The results were evaluated at 05, 41 and 78 months after the establishment of the experiment. After 78 months of conducting the experiment, positive action of the four plant species in the reclamation of soil aggregation was observed, especially for Urochloa brizantha that showed the lowest bulk density and the highest values of macroporosity. The species provided a structural improvement in the constructed soil, mainly after 41 months of conducting the experiment when there was an increase in the values of MWD, mainly in the 0.00 to 0.1 m layer. The organic carbon contents were increased over time, however, did not result in increased of MWD at 78 months.