Revista Ambiente & Água - An Interdisciplinary Journal of Applied Science

1-15

Authors: Maria da Conceição Rabelo Gomes; Adryane Gorayeb; Dimas de Brito Souza; Raquel Morais Silva

This research evaluated the levels of alteration of aquifers caused by installation of wind farms on dunes on the coast of Ceará, using the GOD and POSH methods of vulnerability, underground flow, and the application of multivariate analysis to subsidize the monitoring of groundwater quality in the area. There were three stages of field study: registering the wells and pollution sources, measuring the water levels, and groundwater sampling for laboratory analysis. The results obtained with the GOD method demonstrate the predominance of moderate- to high natural vulnerability of the aquifer to pollution in the areas close to the wind park in the district of Amarelas (Xavier and Ziu beach) and revealed high pollution loads according to the POSH method. The directional vectors of the underground flow are meaningful for Xavier Beach (high vulnerability), the center of Amarelas (moderate vulnerability), Tapuiu and Montevideo (low vulnerability). This indicated that the wind farm may have a potential impact on the lowering of groundwater in the area. From the multivariate analysis, it is evident that the groundwater characteristics are strongly related to the geological formation of the wells (Dunas and Barreiras), showing all samples within the Tolerable Maximum Value for human consumption for TDS, hardness, turbidity, and pH. It is vital to carry out preliminary studies of the aquifers underlying the areas where wind farms are to be installed, considering the levels of vulnerability and the risks of pollution and alteration of the water supply.

1-10

Authors: Nílberte Muniz de Sousa; Willames de Albuquerque Soares; Simone Rosa da Silva; Elivelthon Carlos do Nascimento

Urbanization is directly linked to the process of impermeabilization of the soil in urban areas that contributes to the emergence of flood risks. The purpose of this study was to determine the hydrodynamic properties of the public squares in a flood-prone Brazilian city and determine to what extent they could contribute to the reduction of flooding. The Beerkan method was used to determine the hydrodynamic properties of the soil in nine squares located at critical flooding points in the city of Recife. This method uses simple ring infiltration and the collection of soil samples to obtain the soil granulometric distribution, thereby generating the soil water retention curve θ(h) and the hydraulic conductivity K(θ). The squares studied have similar hydrodynamic characteristics because of their similar soil texture classes, such as Loamy Sand and Sandy Loam. This made it possible for eight of the nine squares studied to be able to contribute positively to the reduction of flood risks by adapting them into micro infiltration basins that can receive the surface flows that overload the drainage network.

1-15

Authors: Edna Maria Bonfim-Silva; Maria Débora Loiola Bezerra; Tonny José Araújo da Silva; William Fenner; Ana Paula Alves Barreto Damasceno

This study evaluated the production of Paiaguás grass (Urochloa brizantha) as a function of wood-ash doses and water availability in the Cerrado Oxisol. The experiment was carried out in a greenhouse with a randomized block design in a fractioned 5x5 factorial scheme, corresponding to five wood-ash doses (0; 8; 16; 24 and 32 g dm-3) and five soil water-availability scenarios (4; 8; 16; 32; 64 kPa) with four repetitions. The experimental design was based on the modified central compound and consisted of 13 treatments of wood-ash doses (g dm-3) and soil water-availability scenarios (kPa): 0-4; 0-16; 0-64; 8-8; 8-32; 16-4; 16-16; 16-64; 24-8; 24-32; 32-4; 32-16; 32-64. Soil volumetric moisture was monitored daily by means of the Diviner 2000 Capacitance Probe® for soil water replenishment according to the treatments. In 30-day intervals, three cuts were performed in the aerial part of the plants evaluating dry mass of leaves, stems, aerial part, number of leaves and of tillers. Data were subjected to analysis of variance and when significant to regression analysis, both up to 5% of error probability, through the statistical program SISVAR and response surface study using SAS. The combinations of wood ash doses with water soil tensions influence the productive characteristics of Paiaguás grass. Fertilization with wood ash reduces the effect of water stress on Paiaguás grass and this residue may be a viable alternative to partial replacement of mineral fertilization and safe disposal in the environment.

1-20

Authors: Alexandre Almeida Del Savio; Samuel Ismael Quisca Astocahuana; Leonardo Franco Castillo Navarro

Debris flows are geophysical phenomena, caused by torrential rain, which occur in mountainous areas, characterized by the detachment of slope and riverbed materials and their consequent dislodge through watersheds and streams. Debris flows usually carry sludge, water and rocks, and can destroy everything in their path. On February 8th, 2019, an event of this type occurred and destroyed Mirave’s community in Peru, which was located in the areas of transport and deposition of debris flows. This research presents the modeling and numerical simulation to reproduce the transport and deposition processes of the debris flow that occurred in Mirave. The initiation process of the debris flow in streams was represented by hydrographs obtained from the estimated rain runoff volumes and solid materials found at each evaluated micro watershed. The numerical simulation results show acceptable results in terms of reproduction of the extension of the affectation and deposition areas of solids related to the studied debris flow. The resulting velocity field shows an adequate representation of the erosion zones observed in the area. The model used for evaluating the disaster risk by debris flows can predict and delimit, with acceptable accuracy, the potentially dangerous areas for a mudslide event. The application of the proposed methodology for assessing the disaster risk due to debris flows at watersheds and streams is useful to understand the extent of debris flow affectation during extreme weather events, as well as to develop emergency plans, and to formulate disaster management policies in Peru or in other countries with similar conditions.

1-10

Authors: Arnon Jadir Rodrigues Alves; Leandro Tiago Manera; Marcel Veloso Campos

The objective of this work is to explore the implementation of a low-cost real-time monitoring and control of water consumption together with a user feedback interface. Water usage information will be available in a cloud storage and can be accessed through a mobile application. The collected data allows access and supervision of both client- and water concessionaire. Project feasibility is analyzed in terms of hardware and software, as well as each element required for the design. The simulations were carried out with the purpose of verifying system operation, considering the following metrics: transmission rate, signal strength and transmission quality. After the simulations, the hardware and software were integrated, and the final result was presented through a mobile application. This work presents and applies a design and development methodology of Wireless Sensor Network (WSN) using Internet of Things (IoT) technologies and Smart City in water-distribution systems.

1-24

Authors: Juliana Feitosa Felizzola; Anthony D. Cak; Ricardo de Oliveira Figueiredo; Marcelo de Oliveira Lima

Land-use intensification in the "Zona Bragantina" region, an area in the eastern Brazilian Amazon, has accelerated landscape changes from primary forest to a mixture of different land uses: native forest (riparian vegetation), secondary forest, pasture, annual cropland, perennial cropland, bare soil and fallow vegetation, with negative consequences for the stability and equilibrium of river systems. This study examined the temporal and spatial variation of dissolved organic carbon (DOC) and metal concentrations in stream water of the Cumaru (ICU) and São João (ISJ) watersheds from May 2014 to April 2015, to understand the chemical changes in forests and agro-ecosystems during one year. In both watersheds, higher concentrations of dissolved metals (aluminum, sodium, barium, calcium, iron, potassium, magnesium, copper and zinc) and DOC were measured in the rainy season, with considerable variability due to precipitation events. Furthermore, strong spatial variation was observed, with lower conductivity, higher pH, and higher concentrations of DOC and dissolved metals in the downstream reaches, especially for DOC in a small reservoir below a dam in ISJ. Significant human intervention was located in these downstream areas, including nearby agriculture and pasture, and use of stream resources for domestic activity. Sandy soil in these areas likely facilitated leachate processes, mainly in deforested areas, supporting the increased movement of metals from the land to the stream.