Ana Paula Almeida Bertossi

Qualidade da água em microbacias hidrográficas com diferentes coberturas do solo no sul do Espírito Santo

The objective of this work was to evaluate the quality of surface water and groundwater in watersheds characterized by different vegetal cover: pasture, forest and coffee crops. It was developed a water quality index by using the analysis of the main components, which provided the reduction of 13 quality features into two components that explained 91.2% of the total variance. Surface water and groundwater of the watersheds were suitable for human consumption after conventional treatment over the studied period, except the groundwater of watershed covered with pasture in the dry season.

Correlação entre uso da terra e qualidade da água subterrânea

Este trabalho descreve a correlacao entre parâmetros de uso da terra (area agricultada, area edificada, pastagem, solo exposto e vegetacao intermediaria) e de qualidade da agua subterrânea (pH, solidos totais dissolvidos - STD, K+, Na+, Fe+3, Ca+2, Mg+2, NO2-, NO3-, P total e coliformes), no sul do estado do Espirito Santo. A delimitacao da area de influencia de pocos e a identificacao das classes de uso da terra foram feitas utilizando-se Sistema de Informacoes Geograficas. Por meio da analise de correlacao canonica, foi possivel estimar dois indices: indice de uso da terra e indice de qualidade da agua, ambos padronizados. A correlacao canonica foi significativa entre o primeiro par de variaveis canonicas, indicando relacao linear entre os grupos. Desta forma, e possivel afirmar que o uso da terra influenciou a qualidade da agua subterrânea, principalmente pelo incremento da concentracao de alguns elementos quimicos.

SOIL COVER AND CHEMICAL AND PHYSICAL ATTRIBUTES IN OXISOL IN THE ATLANTIC FOREST BIOME

The objective of this study was to evaluate the chemical and physical attributes of different soil cover in a Oxisol with a strong wavy relief in the Atlantic Forest Biome, in which were selected three watersheds, employed with grazing (watershed P), forest (watershed M) and coffee (watershed C). Deformed and not deformed samples were collected in three depths for physical and chemical characterization. The chemical characteristics of soil in different watershed studies presented low levels of fertility. It was observed an elevation of pH in the soil and contents of Ca2+ and Mg2+ in the watersheds P and C in relation to the watershed M. Due to deforestation and the establishment of agriculture and livestock, there was a decrease in the contents of soil organic matter in the watershed P and C, not altering the physical characteristics of the soil in the watershed P. The implementation of coffee plantation is causing a reduction in the soil quality of watershed C in comparison to the watershed P and M, therefore indicating a need to adequate soil management in this area.

Diagnóstico temporal e espacial da qualidade das águas superficiais do Córrego Bandeira, Campo Grande, MS

The occupation and the use of land resulting from human activities can significantly alter the biological, physical and chemical processes of natural systems. Such changes taking place in a watershed can be evaluated by monitoring the quality of the surface water. The aim of this study was to identify the determining factors of surface water quality in the watershed of the Corrego Bandeira River, and to group collection points by similarity of the selected physical and chemical characteristics, so as to verify the effect of seasonality on the quality of the waters under study using techniques of multivariate statistics. Samples of surface water were collected from six points along the Corrego Bandeira River, from its source to the mouth. The physical and chemical variables to be analysed were: thermotolerant coliforms, total phosphorus, total nitrogen, biochemical oxygen demand, total solids, temperature, turbidity, dissolved oxygen and pH. Principal component analysis made possible the selection of three components as indicators of water quality, explaining 75% of the total variance. All of the physical and chemical variables analysed were representative of the variability in surface water quality of the Corrego Bandeira River. Cluster analysis however formed two distinct groupings by quality, which showed different values for the physical and chemical variables, and differed in seasonality.

AVALIAÇÃO DE UM SISTEMA DE IRRIGAÇÃO POR ASPERSÃO EM MALHA EM PASTAGEM

Com o objetivo avaliar a eficiencia e a uniformidade de um sistema de irrigacao por aspersao em malha instalada em uma area de pastagem de Brachiaria brizantha cv. Marandu no municipio de Alegre-ES, a area entre quatro aspersores avaliados foi dividida em subareas quadradas de aproximadamente 3 m x 3 m e coletores foram instalados no centro de cada subarea, de forma que a lâmina coletada representasse sua precipitacao. Apos a montagem da malha de coletores, o sistema de irrigacao foi ligado por um periodo de uma hora e os volumes coletados foram medidos. A uniformidade de aplicacao de agua do sistema foi estimada atraves do Coeficiente de Uniformidade de Christiansen e do Coeficiente de Uniformidade de Distribuicao, alem desses foram calculados a irrigacao real necessaria, a lâmina coletada, aplicada, as perdas do sistema, a eficiencia de aplicacao e a irrigacao total necessaria. Com base nos valores encontrados pode-se concluir que o projeto de irrigacao avaliado apresentou uma uniformidade ruim de aplicacao de agua, a lâmina media aplicada no periodo avaliado foi superior a lâmina real necessaria a cultura irrigada e a eficiencia de aplicacao de agua do sistema encontra-se abaixo do recomendado pela literatura.