En Colombia la Dirección General Marítima (DIMAR) a través del Centro de Investigaciones Oceanográficas e Hidrográficas (CIOH), inició un programa de investigación para identificar las especies presentes en las aguas de lastre de los buques que arriban a puerto colombiano. La primera fase del proyecto se ejecutó en el año 2002 y en esta se analizaron muestras provenientes de 12 buques de tráfico internacional que arribaron a la Bahía de Cartagena, determinando el componente bacteriano, fitoplanctónico y zooplanctónico. Los resultados indican la presencia en las aguas de lastre de las bacterias patógenas Escherichia coli, Pseudomona aeruginosa, Vi brío cholerae, Salmonella sp, Proteus mirabilis, P.vulgaris, Enterobacter sp, Klebsiella pneumoniae y Aeromona hydrophilla. Se reportan especies fitoplanctónicas que no hacen parte de la flora típica de la bahía como las diatomeas Chaetoceros messanensis, C.glandazzi, C.tortissimus, Odontella aurita, Hemidiscus cuneiformis, Ditylum brightwelli, Paralia sulcata, Planktoniella sol, Asterionellopsis glacialis y Pseudoeunotia doliohts y el silicoflagelado Dictyocha polyaetis. De igual manera se encontraron especies zooplanctónicas no reportadas como fauna típica para la bahía corno los copépodos Eucalanus elongatus, Euterpina acutikons, Lucicutia Oithona ovalis y aplurnifera, el chaetognato Sagitta planctonis y el decápodo Lucifer typus. | In Colombia the Dirección General Marítima (DIMAR) with the Centro de Investigaciones Oceanográficas e Hidrográficas (CIOH), initiated a research program to identify the presence of species in ships' ballast water that arrive at Colombian ports. During the first stage of the project executed during year 2002, samples of 12 international ships that arrived at the Cartagena Bay were analyzed determining the bacterial, phytoplanktonic and zooplanktonic components. In the samples were found pathogenic bacteria like Escherichia con, Pseudomona aeruginosa, Vibrio cholerae, Salmonella sp, Proteus mirabilis, P.vulgaris, Enterobacter sp, Klebsiella pneumoniae and Aeromona hydrophilla. As well, were found phytoplanktonic species not previously recorded in the bay like the diatoms Chaetoceros messanensis, C.glandazzi, C.tortissimus, Odontella aurita, Hemidiscus cuneiformis, Ditylum brightwelli, Paralia sulcata, Planktoniella sol, Asterionellopsis glacialis and Pseudoeunotia doliolus and silicoflagellate Dictyocha polyaetis. Also were found zooplanktonic species not previously recorded in the bay like the copepods Eucalanus elongatus, Euterpina acutifrons, Lucicutia clausi, Oithona ovalis and O.plumifera, Sagitta planctonis chaetognat and Lucifer typus decapod. | Published

An experiment was carried out at the Universidade Federal de Lavras, MG, aiming to study the behavior of chrysanthemum cultivated in a greenhouse under three different fertigation interruption time, and to evaluate the effects of different levels of water deficits on the plant and the final product quality. A completely randomized experimental design in a factorial outline, with four water consumed replacement levels (100, 80, 60 and, 40%) and three fertigation interruption time (20, 40 and 60% of open inflorescences) with six replications was wed. The analyzed parameters were: stem length and diameter, leaves number, inflorescence number, inflorescence diameter, dry and wet roots matter, and quality classes. The best results were obtained with a 100% of water replacement, exception for stem length where the best results were obtained with a 100 and 80% of water replacement. Fertigation interruption time just influenced inflorescence diameter. The largest inflorescence diameter was obtained when fertigation was interrupted after 60% of inflorescence opening. Dry and wet root matter showed no significant response to the applied treatments. | Conduziu-se um experimento na Universidade Federal de Lavras, MG, com os objetivos de estudar o comportamento da cultura do crisântemo, cultivado em estufa, referentes a três épocas de suspensão da fertirrigação e avaliar os efeitos de diferentes níveis de déficits hídricos sobre a planta e a qualidade do produto final. O delineamento foi inteiramente casualizado em esquema fatorial, com quatro níveis de reposição da água consumida (100, 80, 60 e 40%) e três épocas de suspensão da fertirrigação (20, 40 e 60% das inflorescências abertas) com seis repetições. Os parâmetros analisados foram: comprimento e diâmetro da haste, número de folhas, número de inflorescência, diâmetro das inflorescências, matérias fresca e seca das raízes e classes de qualidade. Com a reposição de 100% da água consumida, obtiveram-se os melhores resultados, exceto para a altura da haste, em que os melhores resultados foram obtidos com reposição de 100 e 80% da água con­sumida. As épocas de suspensão da fertirrigação influenciaram apenas o diâmetro das inflorescências, contatando-se que as maiores inflorescências foram obtidas suspendendo a fertirrigação quando 60% das inflorescências apresentavam abertas. Observou-se para as matérias fresca e seca efeito não-significativo tanto dos tratamentos aplicados.

Determina el estado situacional de las fuentes de agua superficial en el ámbito de la cuenca Yauca, localizado en las provincias de Lucanas y Parinacochas del departamento de Ayacucho y la provincia de Caravelí del departamento de Arequipa.

The malacological fauna of the Agua Dulce/El Ermitaño lagoon estuarine system was characterized and its relation to some environmental parameters determined. Five samplings were carried out in January, August, October and December 1993, and February 1994. Biological, hydrological and sediment samples were taken at seven stations in each water body of the system, located on the northern coast of the state of Jalisco (Mexico). The values of some physical and chemical parameters were recorded and differences were found between both water bodies, mainly in regard to salinity, as an average value of 27 psu was obtained for Agua Dulce lagoon and of 2 psu for El Ermitaño estuary. The qualitative analysis of the sediments showed that the system is made up of four basic types: sandy silt, clayey silt, fine to medium sand and a small part of rocky substrate. The malacological fauna was composed of two classes, Gasteropoda and Bivalvia, the first being the one that presented a greater number of species; 6,782 live organisms and 18,508 dead organisms were collected, corresponding to 17 species of gastropods and 14 bivalves. Of the 31 species collected, only 9 were found alive and some appeared in both water bodies in spite of the salinity gradient recorded in the system. Groups of representative species were identified for four types of environments (marine, >25 psu; euryhaline, 10–18 psu; brackish, 5–10 psu; and freshwater, 0–5 psu). Finally, the most important species were the bivalves Tagelus longisinuatus and Mytella strigata, and the gastropods Rissoella excolpa and Bittium mexicanum, with the highest abundances of the cycle. Low diversity values were obtained (D = 1.5–1.8, Dmax = 2.5); however, they were within those recorded for tropical and subtropical coastal ecosystems.

El rolado es un tratamiento mecánico que trata de solucionar el problema de la baja receptividad y accesibilidad de fachinales o arbustales causados por manejo inadecuado del campo natural en la región chaqueña occidental. El objetivo de este trabajo fue evaluar el efecto instantáneo, y luego de una estación de crecimiento, del rolado y la presencia/ tipo de mantillo sobre el proceso de infiltración de agua en el suelo, un indicador clave de calidad del mismo. Se evaluaron dos ensayos, realizados en 1997 y 1999, respectivamente. Los tratamientos fueron rolado y testigo. La infiltración se evaluó mediante el infiltrómetro de doble anillo, estimándose la velocidad de infiltración mediante el modelo de Kostiakov, que ajustó muy bien a los datos de lámina infiltrada en función del tiempo. Se realizó un análisis de la varianza, empleando como variables independientes: tratamiento (rolado y testigo), sitio de pastizal (alto, media loma y bajo) y presencia/tipo de mantillo (suelo desnudo, mantillo de gramíneas y de leñosas). Las variables dependientes fueron infiltración básica (Ib, mm.h-1) y el tiempo (T, min) que tarda el suelo en generar escorrentía ante una intensidad de precipitación de 75 mm.h-1, evento con un tiempo de retorno de 1,25 años en la zona. A pesar de la gran variabilidad espacial observada en los parámetros de infiltración, los resultados indican que el rolado disminuyó la Ib con respecto al testigo, sugiriendo una modificación del proceso de infiltración en los ecosistemas tratados, aunque el efecto parece ser de corta duración en el tiempo. El efecto fue diferencial por sitio de pastizal, siendo el alto el sitio más afectado. La mayor influencia sobre Ib y T la ejerció la presencia y el tipo de mantillo vegetal (p < 0,05), factor asociado especialmente a la cobertura de leñosas. Se recomienda no pastorear inmediatamente luego del rolado ni tampoco aplicar fuego de manera indiscriminada, a fin de no potenciar este efecto negativo del rolado sobre la calidad de suelos