Environmental Engineering Reference
In-Depth Information
Bulk density of sediment of the study area showed a distinct seasonal variation that was
ranged from 1.22±0.40 to 1.67±0.04gcm
-3
with a minimum value (1.19gcm
-3
) found in winter
and a maximum value (1.74gcm
-3
) recorded in monsoon throughout the sampling period
(Appendix A, Figure 19). Variations in the values of bulk density between monsoon,
postmonsoon, winter and premonsoon were significant at p<0.05 (Table 1). Significantly
(p<0.05) lower value in winter and higher value in monsoon was recorded in this study. Bulk
density of soil showed a significant (p<0.01) positive correlation with water temperature,
dissolved oxygen, total suspended solids, tidal height, inundation period, soil temperature,
percentage of sand, particle density, exchangeable Ca& Mg, total N and total P of soil and a
negative correlation with water salinity, water transparency, water table depth, soil salinity,
soil organic carbon, organic matter, percentage of clay, moisture, field water capacity of soil
(Appendix B). Bulk density also showed a negative correlation with porosity of soil at a level
of p<0.05 in the present study.
Particle density of soil of the study area was varied from 2.80±0.08 to 3.67±0.04 gcm
-3
with a minimum value (2.65gcm
-3
) found in winter and a maximum value (3.67gcm
-3
)
recorded in monsoon throughout the sampling period (Appendix A, Figure 19). Variations in
the values of particle density among monsoon, postmonsoon, winter and premonsoon were
significant at p<0.05 (Table 1). Significantly (p<0.05) higher value in monsoon and lower
value in winter was measured in this study. Particle density of soil showed a positive
correlation with water temperature, dissolved oxygen, total suspended solids, tidal height,
inundation period, soil temperature, percentage of sand, bulk density, exchangeable Ca of soil
at a level of p<0.01. Particle density also showed a positive correlation with exchangeable
Mg, total N and available p along with a negative correlation with silt content in soil at a
significant level of p<0.05 (Appendix B).
2.50
2.00
1.50
1.00
0.50
0.00
Figure 17. Seasonal variation of soil moisture of salt marsh bed of Fauzderhat area of Chittagong coast.
