Water quality indicators in the Mantiqueira Range region, Minas Gerais state

Abstract

Maintaining the quality of water resources is of great importance for environmental preservation and the quality of life of consumers, and is one of the greatest challenges facing humanity today. Land-use for agriculture and animal farming significantly changes the biological, physical and chemical characteristics of natural systems. This study comprised monitoring of two subbasins located in the Mantiqueira Range region, from which water samples were collected on a monthly basis between June 2010 and May 2011 for analysis. Each subbasin has a distinct vegetation cover, one being predominantly covered by pastureland and the other being entirely covered by Atlantic Forest. The following water quality indicators were analyzed: turbidity, pH, electrical conductivity, total dissolved solids, dissolved oxygen, temperature, nitrate, phosphate, BOD, COD, total and fecal coliforms, and respective discharge measurement. The results showed that water quality degradation in both environments coincided with the local rainy season and was influenced by transport of organic material to watercourses by direct surface runoff. The high concentrations of fecal coliforms found affected the water quality, particularly in the rainy season, and are associated with agriculture and animal farming, the main economic activities in the region. The Atlantic Forest environment, however, had statistically better water quality over time in relation to the pastureland environment, due to the buffering it provides to direct surface runoff.

Relação Espacial do Carbono da Vegetação e Matéria Orgânica do Solo na Serra da Mantiqueira

“…A área de estudo consiste em um remanescente de 13,71 ha de floresta ombrófila densa, localizado em uma microbacia hidrográfica experimental no município de Bocaina de Minas, no Estado de Minas Gerais, entre as coordenadas 22° 07' e 22° 09' de latitude S e 44° 26' e 44° 29' de longitude W. O local possui clima superúmido A1, segundo classificação de Thornthwaite, o que significa um balanço hídrico positivo ao longo do ano, e é classificado como Cwb, de acordo com Köppen, o que representa ter verões amenos e chuvosos e invernos frios e secos (Sparovek et al, 2007;Carvalho et al, 2008;Pinto et al, 2013). A temperatura média anual é de 16,7 °C, com médias mensais variando de 13,0 °C em julho a 19,7 °C em janeiro, e a precipitação média anual é de 2.108 mm, com médias mensais entre 341 mm no trimestre mais chuvoso (dezembro a fevereiro) a 35 mm no trimestre mais seco (junho a agosto) (Carvalho et al, 2005 Foi realizado o estudo variográfico por meio do semivariograma experimental isotrópico do ECV e da variável matéria orgânica do solo (MO) para as três profundidades.…”

Hydrologic Impacts Due to the Changes in Riparian Buffer in a Headwater Watershed

“…The Mantiqueira Range region holds several headwaters that form important rivers in southern Minas Gerais state. Its southern region is important for public water supply, irrigation and hydropower (PINTO et al, 2013;VIOLA et al, 2014).…”

“…Because of the soil properties under forest influence, such as litter and soil organic matter, it is possible to assert there will be higher soil porosity and more water infiltration into the soil, thereby reducing surface runoff, erosion, and flash responses to storm rainfall. Thus, the maintenance of riparian areas is fundamental for an environmental balance as it led to greater baseflow/runoff ratio ( Table 2), which is highlighted desirable, and indeed, improves water quality (PINTO et al, 2013;NEARY et al, 2009). …”

A hydropedological approach to a mountainous Clayey Humic Dystrudept in the Mantiqueira Range, southeastern Brazil

“…Despite the TDS values for MPA being lower than those for MFO ( Figure 9) and the significant statistical difference between forest and pasture (Table 4), both TDS concentration values are considered low, according to CONAMA Resolution 357/05, which describes TDS concentrations less than 500 mg L −1 as indicative of preserved environments. The explanations for these results are linked to the geomorphological characteristics of this region, with shallow soils, steep topography and abundant rainfall, where TDS concentrations should be measured soon after the occurrence of rainfall, since these topographic characteristics do prompt a very quick runoff response to this rainfall (Pinto et al, 2013).…”