Revista Ambiente & Água - An Interdisciplinary Journal of Applied Science

1-9

Authors: Luiz Octavio Fabricio dos Santos; Carlos Alexandre Santos Querino* ; Juliane Kayse Albuquerque da Silva Querino; Altemar Lopes Pedreira Junior; Aryanne Resende de Melo Moura; Nadja Gomes Machado; Marcelo Sacardi Biudes

Rainfall is a meteorological variable of great importance for hydric balance and for weather studies. Rainfall estimation, carried out by satellites, has increased the climatological dataset related to precipitation. However, the accuracy of these data is questionable. This paper aimed to validate the estimates done by the Global Precipitation Measurement (GPM) satellite for the mesoregion of Southern Amazonas State, Brazil. The surface data were collected by the National Water Agency – ANA and National Institute of Meteorology – INMET, and is available at both institutions’ websites. The satellite precipitation data were accessed directly from the NASA webpage. Statistical analysis of Pearson correlation was used, as well as the Willmott’s “d” index and errors from the MAE (Mean Absolute Error) and RMSE (Root Mean Square Error). The GPM satellite satisfactorily estimated the precipitation, once it had correlations above 73% and high Willmott coefficients (between 0.86 and 0.97). The MAE and RMSE showed values that varied from 36.50 mm to 72.49 mm and 13.81 mm to 71.76 mm, respectively. Seasonal rain variations are represented accordingly. In some cases, either an underestimation or an overestimation of the rain data was observed. In the yearly totals, a high rate of similarity between the estimated and measured values was observed. We concluded that the GPM-based multi-satellite precipitation estimates can be used, even though they are not 100% reliable. However, adjustments in calibration for the region are necessary and recommended.

1-13

Authors: Allita Rezende dos Santos* ; Renato Carneiro Fernandes da Silva; Leonardo Campos de Assis; Frederico Fábio Mauad

Environmental conservation of river basins in general is essential for water quality and ecological maintenance, especially in spring areas. Despite being characterized as a Conservation Unit (CU) of Sustainable Use (SU), the Uberaba River Basin highlands are highly influenced by anthropic activities. The aim of this study was to determine different levels of conservation required to maintain environmental quality. The Multicriteria evaluation method was used as follows: i) applied fuzzy membership functions to standardization of the continuous data values or reclassified when categorical criteria; (ii) established criteria ranking through the pairwise relative importance comparison approach by the Analytical Hierarchy Process (AHP) method and; (iii) performed Weighted Linear Combination (WLC). The selected criteria were maps of the: land cover obtained by supervised classification of a satellite image, with 94% of Kappa Index of Agreement (KIA); soil types, slope; distances from rivers, roads; railways and urban limits. A main outcome of the criteria evaluated is a map of continuous data values expressing distinct levels of environmental conservation requirements. The highest values that express the need for conservation occurred near the ridgetop, corresponding to forest land cover, high slope and hydromorphic soils. The lowest values were observed in the peri-urban areas, in more stable soil and soil cover with a higher degree of occupation. It is concluded that the resulting map can assist in decision-making regarding proper management of the area, to achieve sustainability in the application of occupation policies.

1-16

Authors: Fernando Gomes de Souza*; Valdinar Ferreira Melo; Wellington Farias Araújo; Thiago Henrique de Castro Araújo

Currently in Brazil, the main form of erosion is caused by the impact of raindrops on the soil surface, triggering the process of water erosion and causing serious damage to agricultural areas. This study evaluated losses of soil, water, organic carbon and nutrients in different cultures, bare soil and savanna under natural rain. The experimental design was completely randomized with five treatments (bare soil - BS, cowpea bean - CB, Brachiaria brizantha - BB, corn - CO and natural savanna – SN) with three replications; The treatment of bare soil (BS), followed by the treatment cultivated with cowpea bean (CB) showed higher losses of soil, water, organic carbon and nutrients; The highest losses of soil, water, organic carbon and nutrients in the treatment of bare soil (BS) occurred during the period of greatest erosivity; but for treatments CB, BB and CO, the highest losses occurred during the establishment of the crop, in view of the lower soil cover. Soils cultivated with Brachiaria brizantha - BB, corn - CO and in the Natural Savana - SN area were more efficient in reducing soil and water losses during all months evaluated. Plant cover produced by the (SN) treatment and by the (BB) and (CO) treatments acted to reduce the harmful effects of erosion, minimizing losses of nutrients and organic carbon. The soil should be well protected during periods when rainfall presents the highest values of erosivity index.

1-15

Authors: Bruna Assis Paim dos Santos; Aline Silva Cossolin; Hélen Cristina Oliveira dos Reis; Ketinny Camargo de Castro; Evanleide Rodrigues da Silva; Gabriele de Menezes Pereira; Paulo Teixeira de Sousa Junior; Evandro Luiz Dall'Oglio; Leonardo Gomes de Vasconcelos; Eduardo Beraldo de Morais*

In this study, baker’s yeast-MnO2 composites, produced by direct oxidation of yeast with KMnO4 under acidic conditions, were used as biosorbent to remove the triphenylmethane dye Malachite green (MG) from an aqueous solution. Parameters that influence the adsorption process, such as pH, contact time, temperature, initial dye concentration and biosorbent dosage, were evaluated in batch experiments. The optimum removal of MG was found to be 86.7 mg g-1 at pH 10, 1.0 g L-1 of biomass dosage and 45°C. The kinetic data of dye removal was better described by the pseudo-second-order model. The adsorption process followed the Langmuir isotherm model and the maximum biosorption capacity was estimated to be 243.9 mg g-1 (at 25°C). The negative values of ∆G° and the positive value of ∆H° indicated that the MG biosorption onto yeast-MnO2 composites is spontaneous and endothermic. Fourier transform infrared spectroscopy (FTIR) indicated that the nano-MnO2 particles deposited on yeast-MnO2 composites surface facilitated the MG adsorption. It was concluded that baker’s yeast-MnO2 composites have potential for application as adsorbent for removal of MG from aqueous solution.

1-9

Authors: Amanda Carvalho Miranda*; Rogerio Bonette Klepa; Thiago Michel Brito de Farias; José Carlos Curvelo Santana

Some classes of drugs represent greater criticality as environmental contamination; antibiotics in general represent the most potent contaminants and cause greater damage to the environment. The purpose of this work is to quantify the percentage of soil contamination by Azithromycin in presentations of 500 mg, through the application of Infrared Spectroscopy with Fourier Transform. It was verified that the drug exerts significant impacts to the environment, even in the characteristic of micropollutant, and that its extraction when performed with Pure Acetonitrile allows its residues in soil samples to be satisfactorily quantified.

1-14

Authors: Josiani Cordova de Oliveira*; Kelly Prado Maia; Nara Linhares Borges de Castro; Sílvia Maria Alves Corrêa Oliveira

Water quality issues are a growing concern due to the the recent intensification of urbanization and industrialization. This paper evaluates and compares the surface water quality of the ten sub-basins of the Pará River, located in the São Francisco River Basin, Minas Gerais, and evaluates the impact of seasonality and the compliance with the current limits of state legislation. The surface water quality monitoring database of the Institute of Water Management of Minas Gerais (Igam) was used, and 18 parameters were analyzed from a historical series from 2008 to 2016, totaling 16,651 observations. First, the descriptive statistics of the parameters were calculated, considering each sub-basin separately. Then, for the temporal and spatial analysis, the Kruskal-Wallis nonparametric statistical tests were applied, followed by the multiple comparison test, with an alpha level of 5%, due to the asymmetric behavior of the data. Thus, it was possible to compare water quality of the sub-basins in rainy and dry seasons and to identify which parameters were responsible for the greater degradation. In the compliance analysis to the current limits of state legislation, it was identified that all of the sub-basins were out of the specified range for at least one of the evaluated parameters. Finally, the seasonality analysis exposed significant differences in the parameters of dissolved oxygen, turbidity, total suspended solids, total solids and water temperature, where it was shown that there was a worsening of water quality in the rainy season for most sub-basins.

1-11

Authors: Sérgio Augusto Rodrigues*; Paulo André de Oliveira; Ricardo Ghantous Cervi; Lilian Cristina Trevizan; Carlos Roberto Padovani

Several factors may contribute to changes in monitoring parameters of drinking water quality, especially climatic characteristics. Behavioral studies of these characteristics are relevant to the rational and sustainable use of water resources and better monitoring of the quality of water available for the population. To assess the association between water quality and climate, this research explored physical-chemical and microbiological characteristics considered important for the monitoring of water quality, analyzed in casual samples collected daily from the distribution system of a city, and considered monthly data of climatic characteristics from 2007 to 2011. The associations between these two sets of variables were assessed by the multivariate procedure of the canonical correlation analysis. The results indicate a positive correlation between the canonical variable formed by the linear combination of climatic variables and the canonical variable formed by the linear combination of water quality variables.

1-10

Authors: Flávia Diniz Mota* ; Roberto Lyra Villas Bôas ; Caroline de Moura D´Andréa Mateus ; Tatiane Bortoletto Gomes da Silva

This study evaluated whether the use of composted sewage sludge in zoysia grass sod production can partially or completely substitute fertilization based on urea. The experiment was conducted on a sod farm located in Itapetininga, São Paulo State, Brazil. The experimental design was a complete randomized block design with five replications and experimental plots of 5 m2 in a 2x6 factorial scheme. The first factor was the method of application (single or split), and the second factor was composted sewage sludge fertilization and two controls (no fertilization and a standard dose of conventional fertilizer). The conventional fertilizer (urea) dose corresponds to 300 kg N ha-1 and the sewage compost doses correspond to 100, 200, 300, and 400 kg N ha-1. The experiment began with the liming of the total area at 60 days after the previous harvest of zoysia grass sod. Three methods were used to evaluate sod production: soil cover rate, green color intensity, and leaf analysis. At 212 days after the beginning of the experiment, the compost treatment of 30 Mg ha-1 (300 kg ha-1 of N), applied in a single dose, allowed for complete sod formation (100% soil cover rate).