ABSTRACT
Polychaete assemblages are relatively poorly known in comparison to other components from Indian waters. In the present study, the spatial and seasonal distributions of polychaetes were investigated in the Thondi coastal area. Polychaete assemblage structure seems to be influenced by environmental parameters, such as temperature, salinity, pH, dissolved oxygen and total organic carbon. A total of 34 polychaete species were found, of which 26 species were in station I while 22 species in station II. There was a pronounced variation in diversity of polychaetes between the studied sites. Among the families maximum percentage of species constituted by Glyceridae (12%) and minimum Owenidae (4%) at station I and in station II, the Eunicidae (14%) was maximum and Pisinidae as (4 %) minimum. The population density varied from 1456 to 2456 no m-2 in station I; 2120 to 4424 in station II and diversity index varied from 1.96 to 2.48 in station I; 2.01 to 2.53 in station II. Species richness varied from 1.21 to 1.65 in station I; 1.36 to 1.69 in station II and evenness index varied from 0.9 to 0.97 in station I; 0.91 to 0.98 in station II. BIO-ENV analysis showed that salinity, TOC and temperature as the key variables in influencing the faunal distribution.
ABSTRACT
Distribution of major groups of enteric bacteria viz., Escherichia coli, Shigella spp., Salmonella spp., Vibrio parahaemolyticus and Vibrio cholerae was studied in the sediment samples collected from different depths of 5, 15, 25 and 35 m in Parangipettai and Cuddalore coast during March, 2009 to February, 2010. Among the bacterial population in Parangipettai, V. parahaemolyticus was found to be maximum with an occurrence of 55% followed by Shigella spp. (15%), V. cholerae (12%), Salmonella spp. (12%) and E. coli (6%). In Cuddalore, as an oddity, Vibrio cholerae emerged as dominant species with an incidence of 60% of the total. V. parahaemolyticus came next in the order with an incidence of 14%, followed by E.coli (11%), Shigella spp. (8%) and Salmonella spp. (7%). Similarly, monsoon and premonsoon seasons registered higher bacterial populations in both the regions. When the depth wise results were viewed, 5 and 15 m depths showed maximum (V. parahaemolyticus 3.7x 10 CFU g-1 in Parangipettai; V. cholera - 8.6x10 CFU g-1 in Cuddalore) bacterial population compared to subsequent depths. Cluster and MDS also showed distinct spatial and seasonal variations of bacterial populations in both the regions. Biota-Environment (BIO - ENV) method revealed the combinations of temperature, salinity and TOC as the best match influencing bacterial population.
ABSTRACT
An attempt was made to find out the impact of shrimp farm discharges on benthic diversity in the discharge point of a shrimp farm. The duration of the study was one culture period right from stocking to harvest. The results revealed that the values of environmental entities were in the safe levels. As regards nutrients, maximum value of TOC and phosphorus were recorded in the sample collected after harvest and minimum in the sample collected during culture. BIO-ENV method revealed that nitrogen, sediment salinity and TOC were manifested as best variable combination explaining faunal distribution. Polychaetes are the dominant group (50%) with 13 species followed by crustaceans (32%) with 10 species, gastropods (10%) with 2 species and bivalves (8%) with 3 species. The faunal density was found to vary in relation to months as observed in the samples which were collected during various seasons in the other areas of estuary. In line with this, diversity values were also paralleled to the faunal density. In a nut shell, the study revealed no negative impact of shrimp farming to the estuarine benthic biota.
ABSTRACT
Background: Long term status of pulmonary tuberculosis (PTB) patients treated with short course chemotherapy (SCC) regimens remains unknown. Objective: To assess the clinical, bacteriological, radiological status and health related quality of life (HRQoL) of PTB patients 14 -18 years after successful treatment with SCC. Methodology: In a cross-sectional study, cured PTB patients treated during 1986 – 1990 at the Tuberculosis Research Centre (TRC) were investigated for their current health status including pulmonary function tests (PFT). The St Georges respiratory questionnaire (SGRQ) was used to assess the HRQoL Results: The mean period after treatment completion for the 363 eligible participants was 16.5yrs (range 14-18 yrs, 84% coverage) ; 25 (7 %) had been re-treated and 52 (14%) died. Among the investigated, 58 (29%) had persistent respiratory symptoms; 170(86%) had radiological sequelae but none had active disease. Abnormal PFT was observed in 96 (65%) with predominantly restrictive type of disease in 66(45%). The SGRQ scores for activity and impact were high implying impairment in HRQoL. Conclusion: Assessment of long term status of cured PTB patients showed an impairment of lung functions and HRQoL highlighting the need to address these issues in the management of TB that may provide added value to patient care.