It is caused primarily by human activities and climatic variations.

Attention should be paid to the implications of each of these farming types in relation to semi arid and dry sub humid ecosystems.

During the next day, its eye became obscured after the mountains of New Caledonia affected Rewa's circulation by creating a hot and dry Foehn wind.

In hot and arid regions, day foraging ants face death by desiccation, so the ability to find the shortest route back to the nest reduces that risk.

Divided along its length by a mountain range, the isthmus's weather is generally wet on the Atlantic (Caribbean) side but has a clearer division into wet and dry seasons on the Pacific side.

Climate Cambodia's climate, like that of the rest of Southeast Asia, is dominated by monsoons, which are known as tropical wet and dry because of the distinctly marked seasonal differences.

The stakeholders and institutions of the affected countries have not yet succeeded in adopting innovative and attractive approaches for medium and long term investments in their arid, semi arid and dry sub humid areas.

Desertification is defined by the United Nations Convention to Combat Desertification as land degradation in arid, semi arid and dry sub humid areas resulting from various factors, including climatic variations and human activities .

Reasserting its commitment to promoting desertification control, eradicating extreme poverty, promoting sustainable development in arid, semi arid and dry sub humid areas and improving the livelihoods of people affected by drought and or desertification,

In Asia, cooperation under TPN 2 on agroforestry and soil conservation in arid, semi arid and dry sub humid areas continued through a workshop that was organized in January 2005 in India.

(j) Finally, since the United Nations Convention to Combat Desertification is recognised as a tool contributing to the goal of eliminating poverty, it would be appropriate to regard the level of investment for managing natural resources in arid, semi arid and dry sub humid areas as an important development indicator.

It is also noted that in a context of a sustained population dynamic in arid, semi arid and dry sub humid dry areas, the strategies to be devised must take account of the characteristics of the land that can be exploited in a sustainable way, so as to support the populations' lifestyles and ways of making a living.