desertification

Question 1

what is desertification

Answer 1

the process by which fertile land becomes desert

Question 2

what are the causes of desertification

Answer 2

poulation growth
over farming/overcultivation
deforestation
over grazing
changing rainfall patterns
soil erosion
drought
water scarcity

Question 3

hoe can planting trees prevent desertification

Answer 3

trees create shade and reduce group temperatures to prevent drought

the roots bind the soil together to prevent soil erosion

leaves and branches fall and decompose returning nutrients back into the soil

trees pull water from the soil and release it into the air which helps create rain and adds moisture to the soil

Question 4

how do rock bunds prevent desertification

Answer 4

prevents soil leave littler and water from being washed away and allows organic matter to decompose adding nutrient to the soil and allows more water to infiltrate

Question 5

how does drought cause desertification

Answer 5

long periods without rain=drought
less water=plants cannot grow=soil dries out cracks and erodes
without plants holding soil together wind and rain can blow or wash topsoil away

Question 6

how does deforestation cause desertification

Answer 6

trees and plants protect soil and keep it moist

cutting down trees =
-no leaves/branches to decompose and return nutrients back into the soil
-no shade so higher ground temp
-roots cant bind soil together means more soil erosion
-trees cannot generate rainfall

Question 7

how does overgrazing cause desertification

Answer 7

too many animals eating plants in one area means=
-animals eat plants faster than they can grow back
-hoves crush soil making it compact so water cannot penetrate
-less plants mean less nutirents retuned to the ground
-soil becomes weak

Question 8

how does overfarming cause desertification

Answer 8

farming repeatedly on the same land removes natural nutrients
-farmers add chamicals to grow crops and soil gets damaged in the long term
-land loses fertility and plant die more easily so more soil is exposed for desertification

Question 9

how does soil erosion cause desertification

Answer 9

soil being blown away by wind or washed away by rain
so topsoil is the most fertile part containing all the nutrients so if it is removed:
-plants cannot grow
-bare land dries out faster and even more soil gets removed
-eventually land becomes hard and infetile

Question 11

how does change in rainfall patterns cause desertification

Answer 11

rainfall becomes less predictable so some areas get less rain and others sudden floods
but plants rely on constant water:
-less rain means soil dries and plants die then erosion

-too much rain washes aways topsoil and land loses fertility

Question 12

how can water scaricty cause desertifiation

Answer 12

not enough water for plants and animals
without water crops die so soil is exposed and erosion increases

Question 13

what are the effects of desetification

Answer 13

food shortages (loss of fertile land means plant cant grow)

• higher food prices
  -migration
  -hunger/malnutrition
  -water scaricty ->increased use of contaminated water->more diseases
  -women and children have to travel long distances to access water ->children miss education