Desertification, climate change and sustainable development.

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Desertification, climate change and sustainable

development

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Introduction

• Desertification is a creeping global problem Deserts cover about 30 % of the earth’s land, and situated mainly between tropical and subtropical regions north and south of the equator, at about 30 north and 30 south latitude. Furthermore, determining which changes are natural and which are human caused is difficult because little is known about the long-term natural dynamics of arid lands.

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Topics of Discussion

• The causes of desertification  and the consequences of desertification

• The measures combating the world desertification• Desertification and global climate change • Desertification and sustainable development• Legal aspects for combating desertification

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Definitions and classifications

• A desert is an area where evaporation exceeds precipitation. Precipitation is typically less than 25 centimeters a year and is often scattered unevenly throughout a year

The classification of deserts based on the level of rainfall combined with different average temperatures. There are tropical, temperate and cold deserts.

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Climate graphs showing typical variations in annual temperature and precipitation in tropical, temperate and polar deserts

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The causes of desertification  

 Overgrazing on fragile arid and semiarid rangelands

 Deforestation without reforestation

 Surface mining without land reclamation

 Irrigation techniques that lead to increased erosion

  Salt buildup and waterlogged soil

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The causes of desertification  

Farming on land with unsuitable terrain or soils

Soil compaction by farm machinery and cattle hoofs

Wind factor

 

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The consequences of desertification

   Worsening drought

    Famine

  Declining living standards

Swelling numbers of environmental refugees

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The measures combating the world desertification

• Each world region has its own unique mix of activities to combat the desertification. Some areas are subject to deforestation or salt buildup due to irrigation, while others suffer from exploitative cropping that depletes soil fertility and aggravates erosion, or from overuse of the land by grazing animals. There is a spectrum of problem evaluations and proposed solutions.

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The most effective ways to combat desertification   Drastically reduce overgrazing

     Reducing deforestation and increasing reforestation

      Reduce the destructive forms of planting, irrigation and mining

  Rationale land use

  Restoring soil fertility by planting trees and grasses with anchor the soil and hold water

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Desertification and global climate change

• Climate change could worsen the effects of desertification. According to the United Nations Framework Convention on Climate Change (FCCC), "countries with arid and semi-arid areas or areas liable to floods, drought and desertification ... are particularly vulnerable to the adverse effects of climate change

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Desertification and sustainable development

Land degradation affects the quantity and quality of freshwater supplies. Drought and desertification are associated with lower water levels in rivers, lakes, and aquifers. For example, unsustainable irrigation practices can dry the rivers that feed large lakes; the Aral Sea and Lake Chad.

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Legal aspects for combating desertification

• The Convention to Combat Desertification was formulated in 1992. This convention has been ratified by more than 60 countries. Along the way, however, the term desertification has been critiqued as being geographically limited.