Environmental Engineering Reference
In-Depth Information
salinity, water table depth, soil salinity, soil organic carbon, organic matter, percentage of
clay, moisture content and field water capacity of soil (Appendix B).
Variations in water table depth of the study area were ranged from 20.24±0.89 to
45.34±1.64cm. The highest water table depth was reached in winter (47.70cm) and the lowest
value (19.30cm) was observed during monsoon (Appendix A). Water table depth gradually
increased from monsoon towards winter and then it decreased in premonsoon again (Figure
11). Variations in water table depth measured
in situ
in different seasons during
study period were significant (p<0.05, Table 1). Significantly (p<0.05) higher value in winter
and lower value in monsoon was recorded. Water table depth was positively correlated with
water salinity, water transparency, soil salinity, soil organic carbon, organic matter,
percentage of clay, moisture content, field water capacity and negatively correlated with
water temperature, dissolved oxygen, total suspended solids, tidal height, inundation period,
percentage of sand, bulk density, particle density, exchangeable Ca & Mg, total N and total P
of soil at 1% level of significance. On the contrary water table depth was negatively
correlated with exchangeable K at the level of p<0.05 in the present study (Appendix B).
Soil temperature of the study area was significantly varied between seasons that were
ranged from 22.18ºC±1.37 to 31.09ºC±4.12 throughout the study period. Minimum
temperature (19.39ºC) was recorded during winter while the maximum temperature (35.78ºC)
was observed during premonsoon (Appendix A).
6.00
5.00
4.00
3.00
2.00
1.00
0.00
Figure 10. Seasonal changes of inundation period of salt marsh bed of Fauzderhat area of Chittagong
coast.
Soil temperature was increased sharply from winter to premonsoon and it slowed down
gradually from monsoon towards winter (Figure 12). Variations in soil temperature between
monsoon and winter as well as the winter and premonsoon were significant at p<0.05 (Table
1). Significantly (p<0.05) higher value in premonsoon and lower value in winter was
recorded. The soil temperature was positively correlated with water temperature, dissolved
oxygen, total suspended solids, tidal height, inundation period, percentage of sand, bulk
density, particle density & the exchangeable Ca and negatively correlated with water
