Desertification has been defined as land degradation in arid, semi-arid and dry sub-humid areas resulting from various factors, including climatic variations and human activities.

Desertification directly affects over 250 million people. It threatens the lives of some 1.2 billion people in 110 countries who are among the world’s poorest and who depend on land for most of their needs.

A third of the Earth’s land surface, or over 4 billion hectares, is threatened by desertification.

Each year, desertification and drought cause an estimated US$ 42 billion in lost agricultural production worldwide. The annual cost of fighting land degradation is estimated at US$ 2.4 billion. Read the rest of this entry »

Deserts cover about one fifth of the Earth’s surface.

With an area of 9,100,000 km2, the Sahara is the largest desert in the world and occupies approximately 10% of the African Continent.

The driest desert of the world is the Atacama Desert in Chile. For the period between 1964 and 2001, the average annual rainfall at the meteorological station in Quillagua was just 0.5 mm.
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Because of its value and its importance in all aspects of life, water is a highly political issue.

International water law concerns the rights and obligations that exist, primarily between States, for the management of transboundary water resources. Such legal rules and principles are dedicated to preventing conflict and promoting cooperation of shared water resources.

The chief international legal document related to international water resources management is the ‘United Nations Convention on the Law of the Non-navigational Uses of International Watercourses’, adopted by the UN General Assembly in May 1997. This Convention applies to uses of international watercourses and of their waters for purposes other than navigation and to measures of protection, preservation and management related to the uses of those watercourses and their waters. Read the rest of this entry »

Erosion is defined as the wearing away and transport of the soil by running water, glaciers, wind or waves. Sedimentation is the process of settling and depositing by gravity of suspended matter in water.

Water transforms landscapes and moves large amounts of soil and fine-grained materials in the form of sediment. Sediment is:
1) eroded from the landscape,
2) transported by river systems and eventually
3) deposited in a riverbed, wetland, lake, reservoir or the ocean.
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Water is used by industry in a myriad of ways: for cleaning, heating and cooling; for generating steam; for transporting dissolved substances or particulates; as a raw material; as a solvent; and as a constituent part of the product itself (e.g. in the beverage industry).

• The water withdrawals for industry is:
• World: 22% of total water use.
• High-income countries: 59% of total water use.
• Low-income countries: 8% of total water use.

Industries based on organic raw materials are the most significant contributors to the organic pollutant load with the food sector being the most important polluter. Read the rest of this entry »