DESERTIFICATION: THE THIRSTY EARTH

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DESERTIFICATION THE THIRSTY EARTH
THE NEWS SUNDAY MAIL
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Bush Drought, Australia
Beyond the broad white rim of pond And the frogs
croaking, No water comes to the parched
land Though her lips are cracking. An inch of
sand to a fathom of rock Is the earths resonance
- Dry white sand where the roots clutch With a
drowned hands seizure. Course grass and brush
and stunted gum Strive here for living. No
illusion of peace has Nature left. No mask of
loving
Her face is harsh, dried hard and lined By the
drenching sun Beneath her pallid skin of dust No
smile is seen No shivering water adds its
groove To the rough sand-marking Only the dark
and sudden stream Of a blacksnakes making. No
sound of rainfall on dead leaves Only the arid
notes Of birds, and the bored frogs clacking
Their castanets
Clive Sansom Witnesses and Other Poems
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Drought vs Desert

• Desert
• a lack of rainfall
• in a state of perpetual drought

• Drought
• An extended period of below average rainfall
• with a high evaporation, rate the rainfall may
  be ineffective

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Desertification changing people, changing
places

• from nomadism to settlement growing populations
  increasing food supply
• use of marginal lands
• overcropping overgrazing
• faulty irrigation - poor drainage
• deforestation
• soil instability... water erosion high
  evaporation... wind erosion
• vulnerability to periods of drought and spreading
  of deserts

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Desertification
The process of deserts spreading onto once
marginal lands. It is the result of the complex
combination of changing climate and human impact.

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Changing Climate?
What do we know? What affects the below average
rainfall?
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Human Impact?
Population Pressures
Herders gather at shallow, hand-dug wells in the
bush
Forests cut-down for fuel and are not given time
to grow back.
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Burning off the hillside to make the dry season
gardens
Economic Realities
From Africa to ... The Amazon
The Harvest Logging companies are increasingly
moving into once inaccessible areas.
The Settlement Farmers clear and exhaust the
land, then sell out to ranchers
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Solutions
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Eight Ways to Prevent Desertification
2. Plant trees along gullies
6. Build ponds to control surface water runoff
1. Reforestation projects
4. Terrace steep land
7. Plant shelter banks and wind banks
8. Stabilize sand dunes
3. Grow tree crops on eyebrow terraces
5. Grow tree crops on eyebrow terraces
From the UN Environment Program