Masato Kobiyama

Influence of compaction of a forest soil on the soil fauna in a subtropical region: I. Oribatei (Acari, Cryptostigmata) and Collembola (Insecta)

An experiment to observe some changes of composition and population of Oribatei and Collembola was carried out on a Cambicsoil covered with Pinus taeda L. (Pinaceae). This study area is located on the Canguiri Experimental Station Center, Universidade Federal do Parana, 20km north to Curitiba city, Brazil. The climate of the area is subtropical. The observations resulted in a conclusion that the compaction strongly changes the structure of edaphic mesofauna community as the consequence of the modification of physical properties of soils.

QUALIDADE DA ÁGUA ORIUNDA DO ESCOAMENTO SUPERFICIAL SIMULADO EM BACIA HIDROGRÁFICA

Dentre as principais fontes de contaminacao dos recursos hidricos tanto superficiais quando subterrâneos, o escoamento superficial destaca-se principalmente no carreamento de substancias contaminantes, acarretando em alteracoes prejudiciais na qualidade da agua. O presente trabalho tem como objetivo a determinacao das caracteristicas fisicas e quimicas da agua oriunda do escoamento superficial da bacia hidrografica do Rio Vacacai-Mirim. Para a realizacao do presente estudo foi utilizado o metodo o metodo “Cornell Sprinkle Infiltrometer”, que promove uma chuva simulada, com tres coletas da agua proveniente do escoamento superficial, aos 3, 30 e 60 minutos. Apos a coleta, foram realizadas testes em laboratorio para a determinacao dos parâmetros (Cloretos, Condutividade Eletrica, Cor, Fluor, Oxigenio Dissolvido, pH, Potassio, Sodio, Solidos Sedimentaveis). Os valores de Cloro variaram de 0,05 a 0,59 mg L-1, Condutividade Eletrica variaram de 31,1 a 188,1 µS cm-1, a Cor oscilou entre 0,9 e 523 uC, as concentracoes de Fluor variaram de 0 a 2,1 mg L-1, o Oxigenio Dissolvido variou de 0,9 a 8,4 mg L-1, o pH variou de 5,7 a 7,41, a concentracao de Potassio variou entre 0 e 20 mg L-1, os valores de Sodio variaram de 2 a 171 mg L-1, a concentracao de Solidos Sedimentaveis variaram de 0,01 a 5.6 mg L-1. Os resultados das analises da variância, nao revelaram interacoes entre os fatores uso e manejo do solo no inicio do escoamento superficial para nenhuma das variaveis estudadas, enquanto que as alteracoes quimicas na agua em funcao do periodo do inicio do escoamento superficial verificou-se efeito significativo apenas na cor da agua.

Water balance in karst: case study of the Ribeirão da Onça catchment in Colombo City, Paraná State - Brazil

O presente trabalho teve como objetivo analisar os processos hidrologicos e avaliar o balanco hidrico da bacia hidrografica do Ribeirao da Onca, no municipio de Colombo/PR, area de manancial da Regiao Metropolitana de Curitiba, para o periodo de monitoramento existente, de 1997 a 2000. Os metodos utilizados foram o do balanco hidrico simplificado e de Penman modificado. O metodo do balanco hidrico mostrou-se invalido para estimar a evapotranspiracao real da area de estudo, por produzir valores negativos e superiores a evapotranspiracao potencial, permitindo inferir que em determinados periodos, o volume de recursos hidricos extraidos e superior ao indice de precipitacao, o que leva a deduzir que existem areas de recarga do aquifero externa aos divisores superficiais da bacia. O balanco hidrico da bacia do Ribeirao da Onca permitiu identificar a contribuicao da agua subterrânea, onde a media anual recebida pela bacia para o periodo de 1998 a 2000, foi de 554 mm/ano.

CORRELAÇÃO DAS VARIÁVEIS PARA MAPEAMENTO DE VULNERABILIDADE AOS DESASTRES HIDROLÓGICOS NO ARROIO FORROMECO-RS

A Analise de Correlacao e um metodo estatistico usado para determinar o grau de relacionamento entre duas ou mais variaveis. Assim, fornece um numero que identifica como duas variaveis variam conjuntamente. Com esse proposito, o presente artigo tem como objetivo estabelecer a correlacao entre as variaveis que determinaram o indice de vulnerabilidade na bacia do Arroio Forromeco, RS, no intuito de reduzir e/ou determinar a importância das variaveis para mapeamentos de vulnerabilidade. Para contemplar o objetivo, utilizou-se dados do Censo do IBGE que permitiram estabelecer o indice de vulnerabilidade por meio das variaveis socioeconomicas. A correlacao matricial resultou em quatro cenarios distintos, apontando novos cenarios para a espacializacao de vulnerabilidade a desastres naturais. Estes cenarios confirmaram areas de maior vulnerabilidade na parte norte-nordeste da bacia, no municipio de Farroupilha e os da parte central-norte da bacia, no municipio de Carlos Barbosa, resultaram em baixa e muito baixa vulnerabilidade. No entanto, a indicacao das variaveis apropriadas para o mapeamento de vulnerabilidade permite maior eficacia na intervencao e tomada de decisao frente a prevencao e ocorrencia de desastres hidrologicos.

Characterization of extreme rainfall events in the Upper Rio Negro Basin, Southern Brazil

Com a utilização de ferramentas do geoprocessamento e da estatística, apresenta-se, neste trabalho, uma metodologia para caracterizar as chuvas relacionadas com eventos extremos ocorridos na bacia superior do Alto Rio Negro, que se encontra na divisa dos estados do Paraná e Santa Catarina. A modelação de eventos extremos, utilizando modelos hidrológicos chuva–vazão, depende da quantidade e da qualidade dos dados das chuvas. O objetivo é a criação de cenários possíveis. A metodologia utilizada consiste em: a) mapear as isoietas da bacia; b) calcular a chuva média diária para a bacia e as sub-bacias; e c) agrupar estatisticamente os eventos para a bacia e as sub-bacias. Os resultados obtidos na análise multivariada foram os seguintes: a) determinaram-se quatro grupos de eventos, b) os parâmetros tempo correspondente à chuva máxima (TPmMax), chuva total durante a tormenta (SPm) e a duração (D) foram os mais influentes na formação desses grupos. Da análise das isoietas, determinou-se a posição do núcleo da tormenta que, na maioria dos casos, situam-se sobre a sub-bacia de rio Negrinho ou nas redondezas. Esses resultados possibilitam a criação de cenários mais realistas que afetam a bacia.

Infiltração e Escoamento Superficial Sob Diferentes Usos e Ocupação em uma Bacia Hidrográfica

With the increase of the area of large urban centers and the reduction of vegetation cover over the soil surface, there is an increase of impervious areas, causing the water from flowing carrying sediments to water courses and reservoirs. In this way the present study aims to analyze the runoff and water infiltration in the soil under different uses and occupancy in Hydrographic Basin. For performing the tests was used the method “Cornell Sprinkle Infiltromete”, while for the determination of compaction was used a digital penetrometer PLG 1020 PenetroLOG ®. Have been observed some areas where there was no runoff (native forests and urban areas) and areas of rice where had the lowest rates. As to the resistance to penetration, native forest had the highest values and the lowest were present in the use of pasture and rice cultivation. The points with higher water infiltration are under the use of native grassland, pasture and soybean, respectively, already the lowest infiltration rates were obtained at points on the use of rice. The variables of time to onset of surface runoff, average rate of runoff and average rate of instantaneous infiltration were subjected to analysis of variance, which did not reveal a significant effect of the use and management of soil, by the F test (5%).

Determination of index risk of river basin vacacaí-mirim with the use of indicators of danger and vulnerability

With the increasing of pollution levels of water resources, whether it surface or underground, With the increasing levels of pollution of water resources, whether surface or underground, appear alternative that aim to establish methodologies used in estimating the natural vulnerability to contamination that aquifer presents. The hazard can be defined as a potential threat to humans and their welfare. Since the risk element can be the probability in which harmful occurrences, and they are economic, social or environmental, resulting from interactions between natural hazards and human systems. This study aim to determine risk, hazard and vulnerability to contamination in the river watershed Vacacai-Mirim. To determine the vulnerability was used GOD methodology (Groundwaterhydraulicconfinement Overlayingstrata Depthtogroundwatertable). The risk was considered to be the product of the hazard estimated by vulnerability, the danger was obtained by reason of the Index of Potential Polluters of the Industry by Socioeconomic Development Index. For municipalities constituents of River watershed Vacacai-Mirim, the socioeconomics index (income, health, and sanitation conditions of households and education) ranged from low to high. Regarding vulnerability to contamination, the values ranged from insignificant to extreme, values of Hazard and Risk ranged from Low / zero to very high. The danger ranged from low to very high, since the risk ranged between low / zero and very high.

Propriedades químicas do solo na bacia hidrográfica do rio Vacacaí-Mirim

The levels of metals in soils have increased gradually with the modernization of agriculture which has occurred in recent years. The human action performed by man in nature is the main cause of this phenomenon. On this basis, the present studys aim is to evaluate changes in soil chemical properties due to different uses and occupations in the river basin of Vacacai-Mirim. The technique used for analysis was EDXRF, where the values were spacialized with the aid of the software Surfer 10. Values for Barium ranged from the detection limit (DL) to 7,608.27 mg/kg-1 with an average of 1,286.71 ± 2,295.18 mg/kg-1, the concentration of Phosphorus ranged from DL to 2,327.02 mg/kg-1 with an average of 676.45 ± 700.05 mg/kg-1, Manganese ranged from DL to 5,533.51 mg/kg-1 with an average of 1,057.34 ± 1,380.81 mg/kg-1, the values for Silicon ranged 229,114.70 to 832,568.70 mg/kg-1 with a mean of 696,134.25 ± 144,950.56 mg/kg-1, Zinc concentration ranged from DL to 429.98 mg/kg-1 with an average of 145.725 ± 123.78 mg/kg-1. Based on these results, it is possible to identify that the concentrations of the metals studied and the land use are closely linked, since concentrations are higher in areas that have agricultural uses, which require larger amounts of chemicals. Thus, it can be observed that the soils under the uses of rice, soybeans and pasture had greater influence on the concentration of the element barium, phosphorus, however, had most influence by the land use in pasture and soybeans.

CARACTERIZAÇÃO FÍSICA E QUÍMICA DO SOLO SOB DIFERENTES USOS EM BACIA HIDROGRÁFICA

The soil has become an essential resource for the survival of human beings, but with the increasing levels of contamination generated by human actions, this resource is getting all this pollution load resulting in changes in their properties. Based on that, this study aimed to characterize the physical and chemical properties of soil under different uses in the Watershed of the Vacacai-Mirim river. The clay content ranged from 8 to 51% with a mean of 28,84 ± 12,18%, the concentration of potassium ranged from 0,8 to 208 mg kg -1 , with a mean of 54,56 ± 47,16 mg kg -1 . The values of organic matter ranged from 0,6 to 2,9%, with a mean of 1,50 ± 0,63%, the concentration of phosphorus ranged from 0,7 to 6 mg kg -1 with a mean of 2,36 ± 1,52 mg kg -1 , the pH values ranged from 4,2 to 5,8 with a mean of 4,76 ± 0,39. Among the analyzed parameters, we highlight the high levels of clay and organic matter in soils that are where the use is native forest and native field, being possible to say that the preservation of the soil contributes to the maintenance of these parameters. Among the chemical attributes, the highest concentrations are related to soils that have undergone human action, such as the ones grown with rice and soybean and the places used as pasture.

Fractal geometry of the drainage network of the Caeté river watershed, Alfredo Wagner-SC

The objective of the present work was to evaluate the fractal dimensions of the drainage network of the Caete river watershed, Alfredo Wagner/SC, with different methods in order to characterize the irregular geomorphologic forms. The drainage network possesses multi-fractal properties. That is why the fractal dimensions for the individual segments (df) and for the entire network (Df) were evaluated with Hortons Laws and the Box-Counting method. The drainage network has self-affinity characteristics. The fractal dimension obtained through the parameters relationship of Hortons Laws showed the results within the thresholds of the fractal geometry theory.