Hypotheses on the mudbanks

The report gives a critical appraisal of the various hypotheses on the formation and the characteristic calmness of the mudbanks, in the light of the author's findings, with special reference to the Alleppey mudbank. A detailed account on various types of mudbanks along the southwest coast of India is also presented

Marine pollution - its effects on living resources with special reference to aquaculture

Due to large scale industrialisation and indiscriminate discharge of effluents with high BOD, toxic chemicals and particulate matter reach the aquatic environment, either directly or indirectly. Enrichment of the coastal waters through nutrients and minerals lead to immediate and long term effects on the biota and fishery resources causing severe eutrophication or mass mortality. Among a large variety of pollutants which reach the aquatic environment, the domestic sewage, agricultural pesticides, industrial wastes, oil and oil dispersants, radioactive wastes and the polluted water from the coconut retting zones causes deleterious effects in the inshore and fish fanning areas

Ecology of mudbanks - Hydrography

The variations in physical and chemical parameters of the Alleppey mudbank waters are discussed in this paper. The fluctuations in tem perature, salinity, oxygen and the comparatively high nutrient contents of the mudbank waters are highlighted

Diurnal variations in the distribution of zooplankton in relation to currents and other ecological parameters of the mud bank of Alleppey, Kerala

Diurnal variations in the distribution of zooplankton biomass of the mud bank at purakkad-Thottappally region south of Alleppey, Kerala h ave been investigated during May and August, 1975. Along with this, observations on currents, hydrography and phytoplankton productivity were also carried out and their effects upon the zooplankton of the mud bank region were studie

Source of mud at Alleppey mudbanks: Its distribution and physical and chemical characteristics

The chapter embodies the authors' findings, and the logical conclusions they drew from them, on the mud cones (or 'mud volcanoes') they found In the intertidal zone and on the beach of the Alleppey mudbank region in 1972. Their experiment with regard to these mud cones confirm beyond doubt the viscous nature of the mud that underlies at Allepey, and its being, for all probability, the source of Alleppey mudbank. Similar mud cones observed earlier by some workers are also discussed briefly

Polymer Translocation in Crowded Environments

We study the effect of the crowded nature of the cellular cytoplasm on the translocation of a polymer through a pore in a membrane. By systematically treating the entropic penalty due to crowding, we show that the translocation dynamics are significantly altered, leading to novel scaling behaviors of the translocation time in terms of chain length. We also observe new and qualitatively different translocation regimes depending upon the extent of crowding, transmembrane chemical potential asymmetry, and polymer length.Comment: 4 figure

Ecology of mudbanks - The current system at Alleppey mudbank

The knowledge of the water currents in the locality being essential for understanding the causes of forma tion, maintenance, movement and dissipation of mudbanks, the current system over two tidal cycles, one in May, before the formation, and the other in August, toward the end of the mudbank period, in 1975, at Alleppey mudbank was studied. Marked difference in the direction and velocity of the current was noticed between the two occasions. In May the effect of the tides was not noticeable on the direction of the current, which was southerly, whereas in August, though the major current con tinued to be southerly, the speed was considerably reduced due to tidal influence. Introducing thereby a northerly component. Along with the current observations, the diurnal changes in the hydrologica! and biological aspects observed in the mudbank are reported

Bioactivity in marine algae

Marine algae have been reponed to possess a wide range of bio active properties (Hashimoto 1979, Baslow 1969, Hoppe, et al. 1979, Hoppe et al. 1984, Blunden et al. 1981, Cocamese et al. 1981, Ramamurthy et al. 1967, Mc Lachan 1964, Byrkholder and Sharma 1969. Conover and Sieburth 1964, Garber et al. 1958). Quite recently, Naqvi et al. (1980) studied the bioactivities of 25 species of marine algae and sea grasses collected mainly from the North Eastern coast of India and a few from the coast of Tamil Nadu

Weak Long-Ranged Casimir Attraction in Colloidal Crystals

We investigate the influence of geometric confinement on the free energy of an idealized model for charge-stabilized colloidal suspensions. The mean-field Poisson-Boltzmann formulation for this system predicts pure repulsion among macroionic colloidal spheres. Fluctuations in the simple ions' distribution provide a mechanism for the macroions to attract each other at large separations. Although this Casimir interaction is long-ranged, it is too weak to influence colloidal crystals' dynamics.Comment: 5 pages 2 figures ReVTe

Productivity of different mangrove ecosystems

This paper embodies the results of field studies conducted on productivity in three different mangrove areas, viz.. Cochin Backwater, Killai Backwater and Andaman Nicobar Islands. The rate of production varied in these areas, but generally indicated a good production rate. The energy inputs from various sources into the ecosystem and the process of conversion are discussed in the light of an overall energy budget available. The productivity of adjacent marine environments is also discussed in the light of their suitability for development of mariculture practices