Showing papers by "Universidad del Norte, Colombia published in 1990"
TL;DR: Experimental harvesting of stipes above the first dichotomy reduces stipe movement and inter-stipe friction, allowing the development of a heavy epiphytic load and increased grazing in lessonia nigrescens and L. trabeculata.
Abstract: Lessonia nigrescens and L. trabeculata are economically important canopy-forming kelps in Chile. Experimental harvesting of stipes above the first dichotomy reduces stipe movement and inter-stipe friction, allowing the development of a heavy epiphytic load and increased grazing. Complete stipe removal leads to holdfast death as neither species is able to simultaneously regenerate all stipes. The invertebrate fauna inside the holdfast does not respond to upper canopy changes, but mortality does occur in partial or complete plant removals. Kelp removal also affects inter-plant distances, results in increased access of grazers to the outside and inside of kelp holdfasts, reduces recruitment of other algal species, and modifies the morphology of L. trabeculata such that the plants become more susceptible to removal by water movement.
39 citations
TL;DR: In this paper, generalized cubic equations of state are applied to the calculation of vapor-liquid equilibrium of H 2 n-alkane mixtures, and generalized correlations are proposed.
26 citations
TL;DR: This preliminary work suggests that L. trabeculata follows an annual growth cycle similar to that of other Laminariales with a high rate of blade elongation during the summer and decreasing towards autumn, considered a potential candidate for aquaculture to increase the availability of raw material and aid in repopulation of overexploited areas.
Abstract: Lessonia trabeculata is one of the major kelps found along the northern coast of Chile. In addition to its ecological and economic importance, L. trabeculata may be severely affected by environmental disturbances such as El Nino, which during 1982–1983 cleared wide areas along the coast of Peru and Chile. The main goal of this work was to mass culture L. trabeculata and to observe the growth of sporophytes obtained in the laboratory and cultured in the sea. Juvenile sporophytes obtained in the laboratory were attached between 1 and 6 m in depth. The linear growth rate, as blade elongation, was recorded weekly for seven months. No significant differences (p < 0.05) were found in sporophyte blade linear growth at different depths. The best elongation growth rate was 7.5 ± 1.6 mm d-1 at 3 m during March. This preliminary work suggests that L. trabeculata follows an annual growth cycle similar to that of other Laminariales with a high rate of blade elongation during the summer and decreasing towards autumn. This species can be considered a potential candidate for aquaculture to increase the availability of raw material and aid in repopulation of overexploited areas.
18 citations
TL;DR: A new species of archinemertean, Procephalothrix hermaphroditicus, is fully described and illustrated from specimens collected intertidally at Cocholgue and Metri, Chile.
Abstract: A new species of archinemertean, Procephalothrix hermaphroditicus, is fully described and illustrated from specimens collected intertidally at Cocholgue and Metri, Chile The species is both the first member of the genus to be reported from Chilean waters, and the first recorded hermaphroditic archinemertean The systematics of the genus and its contained species are discussed
12 citations
TL;DR: In this paper, the presence of metal concentration of marine sediments in Tongoy and Herradura bays, Coquimbo, Chile was determined by analyzing 288 sediment samples taken from two shallow bays in northern Chile during March, June, August and November 1987.
12 citations