Análise foliar de Urochloa decumbens e identificação de plantas invasoras em área de recuperação de depósito de metalurgia de zinco

Abstract

The metallurgical industries generate large amount of solid waste, which can cause negative environmental impacts. The objective of this study was to characterize the metal levels present in the leaves of Brachiaria decumbens and to identify the invasive plants in the area of ​​the old zinc metallurgy tailings deposit. The area selected was from an old waste dump called Area PH9. The area has 14.4 ha and is located in the municipality of Três Marias - MG. Soil samples were collected using two - way walk, north - south and east - west, totaling 29 georeferenced and distanced sampling points every 20 meters. At each point, the leaf was collected and placed in paper bags and taken to the Unimontes Laboratory, Campus Janaúba - MG. Where nitro perchloric digestion was performed and later all samples were transported to the Laboratory of UFMG - Campus Belo Horizonte for the analysis at ICP-OS. The statistical method used was the descriptive statistical analysis, observing the values ​​of the elements of each soil sampling point, highlighting the maximum, average, minimum and total values. Brachiaria decumbens plants presented high levels of calcium, magnesium and iron in the leaves. Zinc contents were below ideal for Brachiaria decumbens plants. Nine shrub invasive species were identified in the area, making up a total of six families, with Graminea being the main one.