First-Order Kinetics-Controlled Multiple Species Reactive Transport of Dissolved Organic Compounds in Groundwater: Development and Application of a Numberical Model

Reactive chemical transport models developed over the past decade have generally relied on the assumption that local thermodynamic equilibrium is achieved at all times between aqueous species in a given system. Consequently, homogeneous aqueous systems characterized by a number of kinetically slow reactions, particularly problems involving organic species, cannot be satisfactorily modeled. In this study, we present a prototype computer model, KINETRAN, which is designed to handle kinetically-controlled homogeneous reactions in the aqueous phase, along with the transport of the various species involved, through geologic media. 31 refs., 53 figs., 10 tabs

A radio tracking study of home range and movements of the marsupial Micoureus demerarae (Thomas) (Mammalia, Didelphidae) in the Atlantic forest of south-eastern Brazil

From August 2001 to July 2002 the home range and movements of seven Micoureus demerarae (Thomas, 1905) (three males and four females) were investigated using radio tracking in the União Biological Reserve, state of Rio de Janeiro, south-eastern Brazil. A total of 436 locations was obtained and home range estimated with fixed Kernel (95% of data points), and minimum convex polygon (MCP) methods, with 100 and 95% of data points. Male home ranges estimated by MCP (100%) ranged from 5.4-24.2 ha and females from 0.3-10.7 ha. Corresponding figures calculated with Kernel (95%) were 4-10.9 ha for males and 1.3-5.9 ha for females. Animals travelled on average 423 m/night, with males travelling significantly further (582.8 m/night) than females (335.1 m/night) (t test, t = 3.609, p = 0.001). We concluded that radio tracking produced much larger home ranges than those estimated with traditional live-trapping techniques, suggesting that the latter might underestimate ranging when the area covered with traps is relatively small (ca. 1 ha or less). Radio tracking also indicated that M. demerarae, although predominantly arboreal and weighting only ca. 130 g., has movements similar in magnitude to larger-sized terrestrial didelphimorph marsupials, such as Didelphis Linnaeus, 1758, Philander Linnaeus, 1758 and Metachirus (Desmarest, 1817).<br>No período de agosto de 2001 a julho de 2002 a área de uso e o movimento de sete Micoureus demerarae (Thomas, 1905) (três machos e quatro fêmeas) foram acompanhados, através de rádio-telemetria, na Reserva Biológica União, Rio de Janeiro, sudeste do Brasil. Foi obtido um total de 436 localizações e estimou-se a área de uso através dos métodos Kernel fixo (95% das localizações) e polígono mínimo convexo (PMC), com 100 e 95% das localizações. A área de uso dos machos estimada pelo PMC (100%) variou de 5,4-24,2 ha e fêmeas de 0,3-10,7 ha. Áreas calculadas com Kernel (95%) foram 4-10,9 ha para machos e 1,3-5,9 ha para fêmeas. Os animais locomoveram em média 423 m/noite, com machos se deslocando mais (582,8 m/noite) que as fêmeas (335,1 m/noite) (Teste t; t = 3,609; p = 0,001). Concluímos que o rádio rastreamento proporcionou áreas de uso superiores ao de estudos tradicionais realizados com capturas em armadilhas, sugerindo que pode haver uma subestimativa quando a área coberta com armadilhas é relativamente pequena (1 ha ou menos). O rádio-rastreamento também indicou que M. demerarae, embora seja predominantemente arborícola e pesa cerca de 130 g, possui movimentos semelhantes em magnitude a marsupiais terrestres de maior porte, como Didelphis Linnaeus, 1758, Philander Linnaeus, 1758 and Metachirus (Desmarest, 1817)