69-72<span style="font-size:14.0pt;line-height: 115%;font-family:" times=""... more 69-72<span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">An evaluation of starvation threshold of the newly hatched Balanus amphitrite nauplii (instar; II) has been made at three different temperatures (5, 15 and 25°C). Earlier studies on starvation in crustacean larvae demonstrated Point of No Return (PNR) as an index of starvation. PNR is the state from which no larvae exposed to stress conditions can recover and complete metamorphosis. In this-study Ultimate Recovery Point (URP) has been used as a new index of starvation threshold. URP denotes the number of hours of starvation after the end of which larvae can recover and continue development. Larvae starved at 5 and 25°C had URP of 204 hand 24 h...
ASEAN Journal on Science and Technology for Development, 2020
The ecological health of port environments, which are dynamic and hotspots of anthropogenic activ... more The ecological health of port environments, which are dynamic and hotspots of anthropogenic activities, can be analyzed using specific pathogenic bacteria as they provide definite evidence and source of pollution. The influence of seasons and environmental settings on total bacterial count (TBC), distribution of fecal indicators, and Vibrio spp. was explored in Visakhapatnam port, located along the east coast of India. South-west monsoon had a significant influence on TBC, fecal indicators, and Vibrio spp., and the abundance was influenced by the eutrophic environment in the inner harbour. Fecal indicators were one order higher in sub-surface water when compared with sediment, indicating their inoculation due to turbulent conditions in south-west monsoon. The abundance of V. cholerae was influenced by salinity, temperature, and SPM, and was positively correlated to plankton; relating their distribution with disease dynamics and ecosystem functioning is a step ahead. Such an assessme...
Operational and Environmental Consequences of Large Industrial Cooling Water Systems, 2011
Barnacles are among the “most-unwanted” by ship owners and those involved in the marine industry,... more Barnacles are among the “most-unwanted” by ship owners and those involved in the marine industry, especially people entrusted with maintaining marine structures as smooth as possible. Barnacles are arthropods, in the same major group as insects and spiders. They ...
ASEAN Journal on Science and Technology for Development
Limited knowledge of native marine biodiversity hinders effective biodiversity management to safe... more Limited knowledge of native marine biodiversity hinders effective biodiversity management to safeguard South and Southeast Asia’s marine coastal environment against the threat of invasive species transfer through shipping. In particular, sessile marine biofouling organisms in South East Asian ports are poorly known. Through the support of the ASEAN-India Cooperation Project on the Extent of Transfer of Alien Invasive Organisms in South/South East Asia Region by Shipping, a coordinated effort to examine diversity of biofouling organisms in major port areas in Southeast Asia and India was made using polyvinylchloride (PVC) panels as recruitment surfaces in a static immersion study for a period of 12 months. Not surprisingly, the study revealed that fouling patterns differed between ports possibly as a result of dissimilar hydrographic conditions. However, there were also underlying similarities that reflected a regional uniformity in the composition of fouling communities. At the same...
ASEAN Journal on Science and Technology for Development
Biofouling community structure was studied in a tropical monsoon-influenced Mandovi estuary in Go... more Biofouling community structure was studied in a tropical monsoon-influenced Mandovi estuary in Goa, west coast of India. Monthly, seasonal and yearly observations on biofouling on polyvinyl chloride (PVC) panels immersed at subsurface water level were recorded and photographed from May 2012 to September 2013. The barnacle Balanus amphitrite was the dominant fouling organism followed by calcareous polychaetes. The settlement and recruitment of barnacles took place year-round, with the exception of July 2012 and June 2013 (monsoon months). However, their peak abundance was observed during the later months of monsoon (August and September). Polychaetes were dominant during late post-monsoon and pre-monsoon months (December 2012 to April 2013). Silt and slime were observed throughout the observation period. Comparing the fouling pressure of barnacles in the two monsoon seasons (2012 and 2013), fouling was more intense during the monsoon of 2013, indicating an inter-annual variation in t...
ASEAN Journal on Science and Technology for Development
Rapid and species-specific detection, and quantification of pathogenic bacteria are fundamental f... more Rapid and species-specific detection, and quantification of pathogenic bacteria are fundamental for monitoring and assessment of the risk they pose to any ecosystem. The study employed Vibrio cholerae, a human pathogen responsible for the life-threatening diarrhoeal disease, cholera and one among the most unwanted from marine bioinvasion point of view. The present study coupled fluorescence in situ hybridization (FISH) technique, a powerful tool in molecular phylogenetic discrimination, with flow cytometry (FCM), a technique used for rapid and accurate quantification of both viable but non-cultivable and non-viable microorganisms. The FISH-FCM technique was used for the first time to quantify V. cholerae (includes cultivable and non-cultivable) from different geographic regions of Southeast Asia (Brunei, Indonesia, Lao PDR, Myanmar, Philippines, Singapore, Thailand, Vietnam) and India (Goa, west coast of India). The data acquired from the analyses provides a snap shot view of the to...
The present article summarizes the research done at the CSIR–National Institute of Oceanography i... more The present article summarizes the research done at the CSIR–National Institute of Oceanography in 2014 in ocean science, resources and technology. Significant research has been conducted on air–sea interactions and coastal circulation, biogeochemistry, biology, marine geophysics, palaeoceanography, marine fishery, gas hydrates and wave energy. Technological advances covered topics like oceanographic tools. Major strides have been made in marine resources research and evaluation.
Diatoms are the earliest autotrophic colonizers and are responsible for the major input of energy... more Diatoms are the earliest autotrophic colonizers and are responsible for the major input of energy in the form of reduced carbon to the surfce. However, information regarding the population structure of diatoms in theearly phases of fouling is very limited. In the present study, enumeration of fouling diatom population was carried out by exposing different types of substrata for four consecutive days at the sub-surface level. The study was carried out at Dona Paula bay located at the mouth of the Zuari estuary along the west cost of India. Quantification of the attached organisms from different substrata and from the surrounding environment was carried out microscopically and by the chlorophyll a estimation. navicula sp. was the most abundant form encountered. The paper deals with the qualitative and quantitative aspects of diatom colonization, their community structure, and correlation between the prevailing diatom population in the environment and that in the fouling community
Energy content in the non-feeding (lecithotrophic) cyprid larvae of B. amphitrite plays an import... more Energy content in the non-feeding (lecithotrophic) cyprid larvae of B. amphitrite plays an important role in determining its metamorphic characteristics. In this context it is important to understand the energy transformed to this stage from naupliar instars and the influence of the different environmental stresses that regulate it. From the antifouling assay perspective, it is also important to produce cyprids at energy level that mimic the stock in nature. In pursuit of this gobal, the capability of the larvae of a barnacle, B. amphitrite to starve at different temperatures (5, 15 and 25 degrees C) was examined. At 5plus or minus, the larvae could recover back and metamorphose after 204h (8.3%); where as at 25 degrees C this was 36h (12.5%). The impact of this factor on larval recruitment is discussed
An evaluation of starvation threshold of the newly hatched Balanus amphitrite nauplii (instar, II... more An evaluation of starvation threshold of the newly hatched Balanus amphitrite nauplii (instar, II) has been made at three different temperatures (5, 15 and 25°C). Earlier studies on starvation in crustacean larvae demonstrated Point of No Return (PNR) as an index of starvation. PNR is the state from which no larvae exposed to stress conditions can recover and complete metamorphosis. In this study Ultimate Recovery' Point (URP) has been used as a new index of starvation threshold. URP denotes the number of hours of starvation after the end of which larvae can recover and continue development. Larvae starved at 5 and 25 °C had URP of 204 h and 24 h respectively. The larvae starved at 5°C for 12 h showed reduced II instar duration (1 d) compared to control II instar duration (1.8 d). At 15 and 25°C reduction in instar duration was not evident.
69-72<span style="font-size:14.0pt;line-height: 115%;font-family:" times=""... more 69-72<span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">An evaluation of starvation threshold of the newly hatched Balanus amphitrite nauplii (instar; II) has been made at three different temperatures (5, 15 and 25°C). Earlier studies on starvation in crustacean larvae demonstrated Point of No Return (PNR) as an index of starvation. PNR is the state from which no larvae exposed to stress conditions can recover and complete metamorphosis. In this-study Ultimate Recovery Point (URP) has been used as a new index of starvation threshold. URP denotes the number of hours of starvation after the end of which larvae can recover and continue development. Larvae starved at 5 and 25°C had URP of 204 hand 24 h...
ASEAN Journal on Science and Technology for Development, 2020
The ecological health of port environments, which are dynamic and hotspots of anthropogenic activ... more The ecological health of port environments, which are dynamic and hotspots of anthropogenic activities, can be analyzed using specific pathogenic bacteria as they provide definite evidence and source of pollution. The influence of seasons and environmental settings on total bacterial count (TBC), distribution of fecal indicators, and Vibrio spp. was explored in Visakhapatnam port, located along the east coast of India. South-west monsoon had a significant influence on TBC, fecal indicators, and Vibrio spp., and the abundance was influenced by the eutrophic environment in the inner harbour. Fecal indicators were one order higher in sub-surface water when compared with sediment, indicating their inoculation due to turbulent conditions in south-west monsoon. The abundance of V. cholerae was influenced by salinity, temperature, and SPM, and was positively correlated to plankton; relating their distribution with disease dynamics and ecosystem functioning is a step ahead. Such an assessme...
Operational and Environmental Consequences of Large Industrial Cooling Water Systems, 2011
Barnacles are among the “most-unwanted” by ship owners and those involved in the marine industry,... more Barnacles are among the “most-unwanted” by ship owners and those involved in the marine industry, especially people entrusted with maintaining marine structures as smooth as possible. Barnacles are arthropods, in the same major group as insects and spiders. They ...
ASEAN Journal on Science and Technology for Development
Limited knowledge of native marine biodiversity hinders effective biodiversity management to safe... more Limited knowledge of native marine biodiversity hinders effective biodiversity management to safeguard South and Southeast Asia’s marine coastal environment against the threat of invasive species transfer through shipping. In particular, sessile marine biofouling organisms in South East Asian ports are poorly known. Through the support of the ASEAN-India Cooperation Project on the Extent of Transfer of Alien Invasive Organisms in South/South East Asia Region by Shipping, a coordinated effort to examine diversity of biofouling organisms in major port areas in Southeast Asia and India was made using polyvinylchloride (PVC) panels as recruitment surfaces in a static immersion study for a period of 12 months. Not surprisingly, the study revealed that fouling patterns differed between ports possibly as a result of dissimilar hydrographic conditions. However, there were also underlying similarities that reflected a regional uniformity in the composition of fouling communities. At the same...
ASEAN Journal on Science and Technology for Development
Biofouling community structure was studied in a tropical monsoon-influenced Mandovi estuary in Go... more Biofouling community structure was studied in a tropical monsoon-influenced Mandovi estuary in Goa, west coast of India. Monthly, seasonal and yearly observations on biofouling on polyvinyl chloride (PVC) panels immersed at subsurface water level were recorded and photographed from May 2012 to September 2013. The barnacle Balanus amphitrite was the dominant fouling organism followed by calcareous polychaetes. The settlement and recruitment of barnacles took place year-round, with the exception of July 2012 and June 2013 (monsoon months). However, their peak abundance was observed during the later months of monsoon (August and September). Polychaetes were dominant during late post-monsoon and pre-monsoon months (December 2012 to April 2013). Silt and slime were observed throughout the observation period. Comparing the fouling pressure of barnacles in the two monsoon seasons (2012 and 2013), fouling was more intense during the monsoon of 2013, indicating an inter-annual variation in t...
ASEAN Journal on Science and Technology for Development
Rapid and species-specific detection, and quantification of pathogenic bacteria are fundamental f... more Rapid and species-specific detection, and quantification of pathogenic bacteria are fundamental for monitoring and assessment of the risk they pose to any ecosystem. The study employed Vibrio cholerae, a human pathogen responsible for the life-threatening diarrhoeal disease, cholera and one among the most unwanted from marine bioinvasion point of view. The present study coupled fluorescence in situ hybridization (FISH) technique, a powerful tool in molecular phylogenetic discrimination, with flow cytometry (FCM), a technique used for rapid and accurate quantification of both viable but non-cultivable and non-viable microorganisms. The FISH-FCM technique was used for the first time to quantify V. cholerae (includes cultivable and non-cultivable) from different geographic regions of Southeast Asia (Brunei, Indonesia, Lao PDR, Myanmar, Philippines, Singapore, Thailand, Vietnam) and India (Goa, west coast of India). The data acquired from the analyses provides a snap shot view of the to...
The present article summarizes the research done at the CSIR–National Institute of Oceanography i... more The present article summarizes the research done at the CSIR–National Institute of Oceanography in 2014 in ocean science, resources and technology. Significant research has been conducted on air–sea interactions and coastal circulation, biogeochemistry, biology, marine geophysics, palaeoceanography, marine fishery, gas hydrates and wave energy. Technological advances covered topics like oceanographic tools. Major strides have been made in marine resources research and evaluation.
Diatoms are the earliest autotrophic colonizers and are responsible for the major input of energy... more Diatoms are the earliest autotrophic colonizers and are responsible for the major input of energy in the form of reduced carbon to the surfce. However, information regarding the population structure of diatoms in theearly phases of fouling is very limited. In the present study, enumeration of fouling diatom population was carried out by exposing different types of substrata for four consecutive days at the sub-surface level. The study was carried out at Dona Paula bay located at the mouth of the Zuari estuary along the west cost of India. Quantification of the attached organisms from different substrata and from the surrounding environment was carried out microscopically and by the chlorophyll a estimation. navicula sp. was the most abundant form encountered. The paper deals with the qualitative and quantitative aspects of diatom colonization, their community structure, and correlation between the prevailing diatom population in the environment and that in the fouling community
Energy content in the non-feeding (lecithotrophic) cyprid larvae of B. amphitrite plays an import... more Energy content in the non-feeding (lecithotrophic) cyprid larvae of B. amphitrite plays an important role in determining its metamorphic characteristics. In this context it is important to understand the energy transformed to this stage from naupliar instars and the influence of the different environmental stresses that regulate it. From the antifouling assay perspective, it is also important to produce cyprids at energy level that mimic the stock in nature. In pursuit of this gobal, the capability of the larvae of a barnacle, B. amphitrite to starve at different temperatures (5, 15 and 25 degrees C) was examined. At 5plus or minus, the larvae could recover back and metamorphose after 204h (8.3%); where as at 25 degrees C this was 36h (12.5%). The impact of this factor on larval recruitment is discussed
An evaluation of starvation threshold of the newly hatched Balanus amphitrite nauplii (instar, II... more An evaluation of starvation threshold of the newly hatched Balanus amphitrite nauplii (instar, II) has been made at three different temperatures (5, 15 and 25°C). Earlier studies on starvation in crustacean larvae demonstrated Point of No Return (PNR) as an index of starvation. PNR is the state from which no larvae exposed to stress conditions can recover and complete metamorphosis. In this study Ultimate Recovery' Point (URP) has been used as a new index of starvation threshold. URP denotes the number of hours of starvation after the end of which larvae can recover and continue development. Larvae starved at 5 and 25 °C had URP of 204 h and 24 h respectively. The larvae starved at 5°C for 12 h showed reduced II instar duration (1 d) compared to control II instar duration (1.8 d). At 15 and 25°C reduction in instar duration was not evident.
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