Water quality variation and nutrient characteristics of Kodungallur-Azhikode Estuary, Kerala, India

Present study focussed on the water quality status in relation to various anthropogenic activities in the Kodungallur- Azhikode Estuary (KAE). Average depth of the estuary was 3.6 ± 0.2 m with maximum of 4.3 ± 0.4 m in the estuarine mouth. Dissolved oxygen showed an average of 5.1±1 mg/l in the water column, whereas the highest BOD value was noticed during monsoon period (3.1 ± 0.8 mg/l) which could be due to high organic enrichment in the water column. pH displayed slightly alkaline condition in most of the stations and it varied from 7.2 ± 0.5 in Station 7 to 7.5 ± 0.5 in Station 1. Salinity in the estuary displayed mixo-mesohaline nature with clear vertical stratification. High river discharge could have resulted in nutrients and silt loading into the estuary, which makes a highly turbid water column particularly during the monsoon period, which limits light penetration and subsequent primary productivity. Turbidity in the water column showed an average of 20.2 ± 15.8 NTU. Estuary was nitrogen limited during post and pre monsoon periods. Nitrate-nitrogen content in the estuarine water gave negative correlation with ammonia.

Ecology And Seasonal Variation Of Microalgal Community In An Oil Refinery Effluent Holding Pond: Monitoring And Assessment

The microalgal community as primary producers has to play a significant role in the biotic and abitoic interactions of any aquatic ecosystem. Whenever a community is exposed to a pollutant, responses can occur because individuals acclimate to pollutant caused changes and selection can occur favouring resistant genotypes within a population and selection among species can result in changes in community structure. The microalgal community of industrial effluent treatment systems are continuously exposed to pollutants and there is little data available on the structure and seasonal variation of microalgal community of industrial effluent holding ponds, especially of a complex effluent like that of refinery. The aim of the present study was to investigate the annual variation in the ecology, biomass, productivity and community structure of the algal community of a refinery effluent holding pond. The results of the study showed the pond to be a eutrophic system with a resistant microalgal community with distinct seasonal variation in species composition

Some Aspects of Domain Specific Conceptual Modeling for Simulation of Logistic Terminal Operations

When simulation modeling is used for performance improvement studies of complex systems such as transport terminals, domain specific conceptual modeling constructs could be used by modelers to create structured models. A two stage procedure which includes identification of the problem characteristics/cluster - ‘knowledge acquisition’ and identification of standard models for the problem cluster – ‘model abstraction’ was found to be effective in creating structured models when applied to certain logistic terminal systems. In this paper we discuss some methods and examples related the knowledge acquisition and model abstraction stages for the development of three different types of model categories of terminal systems

Evaluation of Somaclonal Variation in Callus Cultures of Jatropha curcas Maintained on Different Hormonal Combinations Using RAPD Markers

Random genetic changes generated during in vitro culture are not desirable for plant micropropagation and genetic transformation. RAPD markers were used to detect the variation in leaf disc callus cultures of Jatropha curcas, maintained in Murashige and Skoog (MS) medium with different auxin and cytokinin combinations. In total 41 scorable bands were produced with 11 primers. Out of 41 bands, 37 were polymorphic (91.12%). The average number of polymorphic bands was 3.36 per primer. The highest similarity (0.82) with mother plant was seen in callus maintained on MS with hormonal combination Indole butyric acid - 0.4mg/l+ N6-benzyladenine purine - 4.0 mg/l. The callus grown on MS with hormonal combinations IBA- 0.4mg/l+ BAP- 2.0mg/l, IBA- 0.4mg/l+ BAP- 2.5mg/l and IBA- 0.6 mg/l+ BAP- 2.0 mg/l also showed similarity with the mother plant. Callus maintained on MS with hormonal combination IBA- 0.2mg/l+ BAP- 2.0 mg/l was found to show least similarity (0.53) with mother plant