Water quantity investigation of simulated green roofs in a tropical climate: influence of vegetation composition

Green roofs are recognized as a sustainable infrastructure to improve the environmental quality of cities. Among many benefits, green roofs reduce the rate and volume of runoff helping to improve rainwater management. This study investigated the runoff retention capacity of three pilot extensive green roof assemblies with different vegetation (grass, shrub and intercropping of the two plants). Rainwater runoff data were collected for 18 rainfall events that ranged from a minimum of 1.6 mm to a maximum of 157.9 mm. Average precipitation event retention efficiencies were 46.7, 59.7 and 61.6% for intercropped, shrub and grass green roofs, respectively, while the annual runoff retention rates were 43.8, 57.3 and 59.7%. The difference in retention rates for the green roofs with different vegetation was not statistically significant. The rainfall intensity influenced the retention rates, with the highest retentions for small events (<10.0 mm) followed by medium (10.0-24.9 mm). Retention was found to correspond significantly to rainfall depths. On the other hand, regression analysis failed to provide a relationship between retention and antecedent dry weather period (ADWP). The organic soil used as substrate appears to be the deciding factor for rainwater retention

Quality of water of a dam located in an agricultural area (Campo Verde, MT, Brazil)

In this study spatial and temporal variations in limnological characteristics of a dam located in one of the headwaters of the São Lourenço River (Campo Verde, MT) were evaluated. The surrounding area is used for soybeans cultivation, corn, cotton, and pasture. We examined biotic (heterotrophic bacteria and chlorophyll a) and abiotic factors (precipitation, air and water temperature, electrical conductivity, dissolved oxygen, pH, turbidity, total phosphorus, nitrite, nitrate, and ammonia nitrogen) at three sampling sites along the longitudinal axis of the water body, and at three depths (at the surface, the Secchi depth, and at the sediment-water interface). Samples were taken bimonthly during 2010. Spearman correlation analysis was used to examine the relationship between biotic and abiotic variables, and then principal components and cluster analyses were used to study the relationship between these factors and the variability observed among the various sampling sites, dam depths, and periods of observation. The analyses showed a strong correlation between factors such as rainfall, heterotrophic bacteria, conductivity, turbidity, and phosphorus, indicating the influence of seasonality in cultivated areas. It was observed that the variations between the sampling sites were more significant (p < 0.01) than in the water column for most of the variables, probably due to the particular characteristics of each sample point and its shallow water column

QUALIDADE DAS ÁGUAS DE POÇOS RASOS EM ÁREA COM DÉFICIT DE SANEAMENTO BÁSICO EM CUIABÁ, MT: AVALIAÇÃO MICROBIOLÓGICA, FÍSICO-QUÍMICA E FATORES DE RISCO À SAÚDE

As doenças de veiculação hídrica são responsáveis por milhões de mortes todos os anos no mundo. Tais doenças estão relacionadas à falta de saneamento básico e água de qualidade para consumo humano. Em Cuiabá, MT, o bairro Pedra 90 apresenta problemas relacionados à falta de água em condições adequadas de quantidade e qualidade, o que levou a população a construir poços rasos em suas residências para garantir um abastecimento alternativo. Este trabalho avaliou a qualidade das águas de dezessete desses poços e identificou que os mesmos apresentam contaminação por Escherichia coli e bactérias heterotróficas, provavelmente por estarem próximos às fossas rudimentares que são comuns na região. O consumo dessas águas representa risco à saúde da população

LIMNOLOGY AND WATER QUALITY IN AN URBAN WATERSHED IN NORTH PANTANAL

Studies focused on limnology and quality of water bodies are essential to produce data that support the planning and management, diagnose the current situation and propose measures to minimize the possible negative impacts on water resources. The Tereza Botas creek drains the town of Poconé-MT, situated in the Pantanal border. In this sense, the objective of this study was to verify the variations in limnological characteristics along the longitudinal gradient and evaluate the water quality of the Tereza Botas watershed, identifying the impacts from anthropogenic activities of this important Pantanal watershed. Four sampling points along the longitudinal gradient of the water stream have been defined, and physical, chemical and microbiological variables were analyzed. The results indicated that the changes in limnological and water quality derive from the riparian vegetation removal, erosion and discharge of sewage in natura. In addition, high density of E. coli was observed in most of the sampled points, demonstrating that the lack of proper sanitation as well as the presence of rudimentary cesspit are negatively affecting water quality in the headwaters region

QUALIDADE DA ÁGUA DE UMA MICROBACIA COM FINS DE ABASTECIMENTO PÚBLICO, CHAPADA DOS GUIMARÃES, MT.

A urbanização de forma desordenada tem se elevado nas bacias hidrográficas, a qual pode levar ao desequilíbrio ambiental e, por conseguinte, à saúde humana. Um exemplo deste desequilíbrio é a deterioração da qualidade da água dos corpos d’água. Sabe-se que uma água de qualidade é fundamental à vida humana. Neste sentido, esta pesquisa teve como objetivo medir as condições limnológicas e de qualidade da água da microbacia do córrego do Quineira, a fim de avaliar a atual situação deste importante recurso natural, o qual é utilizado para o abastecimento público do município de Chapada dos Guimarães, Mato Grosso e propor medidas mitigadoras com vistas à proteção ambiental de modo geral, bem como gerar dados que subsidiarão a gestão dos recursos hídricos desta cidade

Morfopedologia aplicada à concepção de obras em microbacia do perímetro urbano de Várzea Grande-MT

Este trabalho, fundamentado na abordagem morfopedol&#243;gica, foi realizado em &#225;rea do per&#237;metro urbano de V&#225;rzea Grande-MT, onde ser&#225; instalado o novo Campus da Universidade Federal de Mato Grosso, tendo por objetivo subsidiar a concep&#231;&#227;o do projeto de obras de infraestrutura para minimizar impactos nos recursos h&#237;dricos. Por meio da elabora&#231;&#227;o de um diagn&#243;stico integrado dos elementos que comp&#245;em o meio f&#237;sico foi poss&#237;vel interpretar o funcionamento h&#237;drico das vertentes e a din&#226;mica dos processos respons&#225;veis pelos impactos ambientais. A an&#225;lise dos resultados, sintetizados em um mapa com cinco compartimentos morfopedol&#243;gicos sobreposto ao projeto de obras do Campus, permitiu levantar os problemas ambientais potenciais e identificar a&#231;&#245;es necess&#225;rias para a minimiza&#231;&#227;o dos impactos nos recursos h&#237;dricos superficiais