Abstract. A quantitative survey (18 stations) of the subtidal soft bottom macroinfauna in an estuary of the south Chilean coast was conducted during January, 1980. The map of sedimentological facies elaborated for the Queule River Estuary shows sandy bottoms in the outlet and upper part of the area studied, while the middle part is occupied by muddy sand. The ordination of stations by Principal Component Analysis is fundamentally defined by mud and gravel percentage and is, in general, concordant with the distribution of sediments in the facies map. A total of 17,405 animals was collected (16 taxa), Polychaeta being the dominant group in density (77.47%) and biomass (73.4%). The maximum number of species was obtained outside the mouth of the estuary, while maximum densities and biomass were obtained in the middle of the estuary. The Factor Analysis performed with the abundances data of the most abundant species rendered the ordination of two groups of stations (concordant with a Cluster Analysis) in the Q‐mode and two groups of species in the R‐mode. One group of stations is restricted to sandy habitats of the outlet area and is dominated by suspension feeders. The other, in the middle and upper part of the estuary (muddy sand or sandy bottoms with a higher percentage of organic matter), is dominated by deposit feeders. Between these two groups, significant differences in sedimentological variables (sand, mud, and organic matter percentage) were detected. Each of the two delineated groups of species corresponds to the groups of stations, showing that most of the taxa can be combined in faunal assemblages with preference for different types of substrate.

Se entrega un catálogo de los Pteridófitos pre sentes, con una breve caracterización de cada uno. De las 76 especies citadas para la región, se encon traron 70 y de éstas, sólo 47 crecían en comunida des boscosas. El espectro biológico presentó una predominancia de hemicriptófitos y epífitos. Se comprobó un aumento del número de especies epi fíticas con la disminución de la luz en el interior del bosque. En forma inversa, a una mayor intensi dad lumínica correspondió un mayor número de hemicriptófitos terrestres.Los bosques de olivillo y de coihue-ulmo pre sentaron el mayor número de helechos, disminu yendo drásticamente la presencia en las otras aso ciaciones boscosas. Mediante el índice de similitud de Ji-cuadrado y con un análisis computacional, se compararon las asociaciones boscosas estudiadas, en su similitud florística pteridofítica. Estos resul tados se presentan en dendrogramas que permiten agrupar las comunidades boscosas en formaciones asimilables a las ya descritas en la literatura.

The mixed partially deciduous roble-laurel-lingue forest (Nothofago-Perseetum linguae) covered the Intermediate Depression in south-central Chile between the cities of Victoria and Puerto Montt. This primitive distribution area was strongly reduced to obtain agriculture and pasture lands. In order to promote the preservation of these endangered plant associations, a floristic and vegetational description was made on the basis of 52 vegetation samples, taken with the Braun-Blanquet phytosociological method in stands of the provinces of Cautín, Valdivia, Osorno and Llanquihue.The flora have 158 species, 80% of them are native and the remaining 20% foreign. The most important trees are: Nothofagus obliqua, Luma apiculata, Persea lingue and Laurelia sempervirens. Among the lianen Chusquea quila and Lapageria rosea, stand out the former because its his high cover and the latter because its frequency. Rubus constrictus and Agrostis capillaris are important species belonging to the foreign elements introduced in these forest stands. Phanerophytes and hemicryptophytes dominate in the biological spectrum. The presence of therophytes with scarce cover, but with many species indicates xeric conditions. The forest is polystratified with a deciduous superior tree layer and a evergreen inferior tree layer. Furthermore, scrub, herb and moss layers are found. Eleven lianen species interconect these layers.The ordering obtained with the principal components analysis, indicates the influence of many environmental factors on the microdistribution of the plant species. The most important are temperature and humidity. The phytosociological ordering separated the few primitive stands from the more intervened ones. Also those with ecotonal characters of the coihue-ulmo forest (Nothofago-Eucryphietum cordifoliae) of the "ñadi" soils from those of the temo-pitra forest (Blepharocalyo-Myrceugenietum exsuccae) of the "hualves". The floristic analysis and the structure of the stands indicates that the majority of them are secondary. However, abundant regeneration of the tree species was found. Finally, a possible secondary anthropogenic degradation is proposed and the conservation of these forest associations is recommended.

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