Page 116 - Navy Journal 219

Navy Journal 2019

c. The soil composition of Bangladesh hilly areas has 95% sand and 5% silt
with clay granules. The cohesive force of sand is almost zero. Therefore, if
vegetation on the hill tops is removed then hills of such soil composition
will definitely slide in course of time.
d. This year 2017 heaviest rainfall accumulation estimates by IMERG
(Multi-satellite Retrievals for GPM) deployed for precipitation
Measurement Missions, NASA were located over southeastern
Bangladesh. IMERG estimates indicated that landslide inducing rainfall
totals there were greater than 510 mm (20 inches). Effect of global climate
change and excessive rain fall soften the uncovered hill and causes sudden
land slide this year.
e. Due to Jhum cultivation burning of hills causes deposit of carbon on the
valley. Deposited carbon increase and decrease of oxygen in the hill valley
are the most favorable condition for thunderbolt during rain and storm.
After thunderbolt the sound shockwave shakes the hill fissure and causes
land slide. 9
f. As a developing country well-developed communication system is
required to exploit the natural resources. In developed countries sustainable
development considers development of roads keeping the natural condition
of topography. In Cox’s Bazar, marine drive was built straightway cutting
the hills in steep forms leaving the roads vulnerable to landslide.

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