landslides

Question 1

define landslides

Answer 1

mass movement of earthen material such as soil moving quickly down a slope influenced by gravity and assisted by rainfall

Question 2

list three causes

Answer 2

heavy rainfall
deforestation
human activities

Question 3

explain how heavy rainfall causes landslides

Answer 3

weighs down soil causing it to become heavy and move down the steep slope

Question 4

explain how deforestation causes landslides

Answer 4

removal of trees on a slope can make soil layers loose therefore will move more readily down a slope

Question 5

explain how human activities cause landslides

Answer 5

mining - include removal of trees and blasting of rocks can cause soil to move down a slope rapidly as landslides
urbanisation - construction of houses on slopes weighs down soil and poor drainage leads to soils becoming saturated with water
poor road construction and maintenance - roads cut poorly on slopes create steep slopes allowing materials to move and broken water lines allowing water to saturate soils leading to landslides formation

Question 6

list five effects of landslides

Answer 6

loss of life, destruction of houses, roads and bridges blocked, agricultural produce lost, soil washed into river courses

Question 7

explain loss of life

Answer 7

in 2004, 2 people died in delaford when a massive landslide covered their home

Question 8

explain destruction of houses

Answer 8

homes on steep slopes in santa cruz, diego martin have been pushed off their foundations or experienced cracked walls due to landslides
get insurance from home owner insurance or short term relief from goverment

Question 9

explain roads and bridges blocked

Answer 9

landslide debris make roads impassable or traps persons
mostly along north coast to maracas bay

Question 10

explain agricultural produce lost

Answer 10

crops and livestock when become covered by landslides especially when farming takes place on hills

Question 11

explain soil washed into river courses

Answer 11

from landslides which river courses cannot hold volume of water it should resulting in any addition of water may lead to flooding

Question 12

how to mitigate landslides

Answer 12

afforestation, retaining walls, benching and terracing, hazard maps

Question 13

explain afforestation

Answer 13

trees planted along steep slopes so soils retained by plant roots and prevent soil from moving down hill
plant grasses like vetiver are planted because of their thick fibrous roots

Question 14

explain retaining walls

Answer 14

constructed against slopes to prevent materials from landslides from moving usually found along roadways

Question 15

explain benching and terracing

Answer 15

steps or benches cut into slopes to reduce the amount and speed at which materials move down a slope
reduces angle of slope

Question 16

landslide hazard map

Answer 16

use of hazard landslide maps to know where to avoid building