Wave propagation in marine sediments and water saturated soils

Wave propagation in marine sediments and water saturated soils

676 Oceanographic Abstracts was employed, q-he filtering rate was very variable and is probably related to size. "Ihere seemed to be a seasonal vari...

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676

Oceanographic Abstracts

was employed, q-he filtering rate was very variable and is probably related to size. "Ihere seemed to be a seasonal variation in filtering rates. During the summer of 1961 weekly water samples were taken for estimation of the particulate carbohydrate in the sea. There was always enough food present for Temora. Respiration was measured by using a modified Winkler method. Oxygen consumption was related to surface area, and corrections in respiratory rates were made for the size differences in the animals used. Respiratory rates were very high at the beginning of an experiment, but after a sharp fall the rate became steady in about 30 h. A n indication of seasonal variation in oxygen uptake was found.

BOLTOVSKOY,E. 1962. Planktonic foraminifera as indicators of different water masses in the South Atlantic. Micropaleontology 8(3): 403-408. The geographic position of the convergence of subtropical and subantarctic waters in the South Atlantic has been determined by means of the planktonic formainifera encountered in 98 surface samples. The species that can be considered indicators of the different water masses and of their mixtures were established, and the results are summarized in a chart showing the distribution of the water masses. BORUT, S. Y. and T. W. JOHNSON,JR. 1962. Some biological observations on fungi in estuarine sediments. Mycologia, 54(2): 181-193. Sixty-eight estuarine sediment samples were cultured for fungi, both on agar media and on balsa wood. Sediments were taken from bottom materials subtending waters in a salinity gradient, but the 142 identified species did not show distributional patterns in response to any single hydrographic factor or group of factors. Spore germination and growth of some species were tested under varying conditions of temperature and salinity, and certain physiological tests were also performed with a few isolates. In no instance was growth completely inhibited by salinity stresses, provided nutrients were available. Germination, however, is markedly influenced by saline conditions, especially that of sea water. B o s c h , E. E. and V. ANGELESCU 1962. Descripcion de la morfologie externa e interna del langostino con algunas aplicaciones de indole taxonomica y biologica. Hymenopenaeus miilleri (Bate) Crustacea, faro. Penaeidae. Bol. lnst. BioL Mar. 1:73 pp. In this paper the external and internal anatomy of the shrimp Hymenopenaeus miilleri (Bate), is described in detail. Special attention is given to those features which are diagnostic or which are significant for a fuller understanding of the biology of this species. The major portion of the paper deals with the description of the cephalopereion, pleon and telson and its appendages, as well as the nervous, respiratory, circulatory, digestive, excretory and reproductive systems. Special attention is given to the digestive system, the stomodaeal apparatus and sexual dimorphism. The relations between form and function of several organs and systems are pointed out. A study is made of the development of the gonads, the sexual cycle in males and females; the variations found in relative weight and size are described. The phylogenetical position of the Penaeidae, the genera of the subfamily Solenocerinae and of H. mtilleri are discussed. The main conclusions are: (1) For the identification of the species it is necessary to use the classical morphological features, in addition to characters taken from the stomodaeal apparatus, especially those pertaining to the pterocardiac, zigncardiac and prepiloric ossicles, and the spines of the cardiac plate. (2) Several morphological adaptations in the structure of certain organs and appendages point towards demersal behaviour: (a) optical organ: eyestalk short with restricted movement; reduced ommatidial surface. (b) mandibular palp large, assisting conduction of water towards the branchial chamber. (c) Propulsory surface of the pleopods and uropods somewhat reduced. (3) Correlations of form and function between different appendages or between different portion of one and the same appendage, such as: (a) Better development of the pereiopods used for resting on the substratum, and reduced natatory capacity of the pleopods and uropods. (b) Enlargement of the molar and incisive surface of the mandible and reduction of the triturating capacity of the stomodeal apparatus. The morphological adaptation and evolution of Hymenopenaeus miilleri is more advanced than i~! other species of penaeids.

BOSE, S. K. 1962. Wave propagation in marine sediments and water saturated soils. Geofis. Pura e Appl. 52(2): 26-40. A unification of the theories of Bint and Weiskopf has been made to provide suitable equations of motion for porous water-saturated soils and marine sediments. It has been shown that the velocities of the body waves depend on the direction of propagation. In the vertical direction there are three one distortional and two dilatational waves. In the horizontal direction there are two dilatational and two distortional waves. Finally, propagation of Love waves and Rayleigh waves have been discussed. Suitable potential functions have been derived to find the frequency equation for Rayleigh waves.