2 research outputs found
Ecosystem Responses in the Distribution of Black Clam (Villorita cyprinoides) Beds in Vembanad Estuary during Environmental Changes Using GIS and RS
The biomass and distribution of black clam (Villorita cyprinoides) in Vembanad,
a tropical estuary located along the southwest coast of India varied significantly.
Sampling was done in freshwater-dominated zone in the south
(distal) and brackish water zone in the north (proximal), during pre and post
monsoon seasons. Clam biomass was estimated from samples, collected from
different stations during the study period. Water transparency and temperature
were measured at the sample sites. Water samples were collected and
analysed for salinity, dissolved oxygen (DO), pH and hardness. There was a
significant difference in the clam biomass during the two seasons in the distal
zone, and those collected from the distal and proximal zones during premonsoon
season. The data were further analysed to determine the factors affecting
the clam biomass distribution in the two zones and seasons. Factor
analyses, comparing the distal zone during two seasons and zonal variations
were similar to earlier observations. Step wise regression analyses found that
dissolved oxygen (adjusted R2 = 0.3) is the only variable affecting clam survival
during pre-monsoon period in the distal and proximal zones. A geographic
map of the region obtained from the Indian satellite sensor LISS
(Linear Image Self Scanner) was used along with in situ data to map the results
using inverse distance weightage model
Not Available
Not AvailableThe biomass and distribution of black clam (Villorita cyprinoides) in Vembanad,
a tropical estuary located along the southwest coast of India varied significantly.
Sampling was done in freshwater-dominated zone in the south
(distal) and brackish water zone in the north (proximal), during pre and post
monsoon seasons. Clam biomass was estimated from samples, collected from
different stations during the study period. Water transparency and temperature
were measured at the sample sites. Water samples were collected and
analysed for salinity, dissolved oxygen (DO), pH and hardness. There was a
significant difference in the clam biomass during the two seasons in the distal
zone, and those collected from the distal and proximal zones during premonsoon
season. The data were further analysed to determine the factors affecting
the clam biomass distribution in the two zones and seasons. Factor
analyses, comparing the distal zone during two seasons and zonal variations
were similar to earlier observations. Step wise regression analyses found that
dissolved oxygen (adjusted R2 = 0.3) is the only variable affecting clam survival
during pre-monsoon period in the distal and proximal zones. A geographic
map of the region obtained from the Indian satellite sensor LISS
(Linear Image Self Scanner) was used along with in situ data to map the results
using inverse distance weightage model.Not Availabl