a recent study has revealed that trees are in significant decline in the Eastern Desert of Egypt. The desert ranks among the most extreme deserts, with average annual rainfall being less than 30 mm. However, the region has widespread dry river valleys called wadis. The researchers monitored Acacia tortilis and Balanites aegyptiaca, found in these wadis. These trees have high drought persistence as their roots can go deep enough to draw permanent sub-soil moisture. These trees also provide raw material for charcoal production.

The researchers used high-resolution imagery from 1965 from the us reconnaissance satellite corona in combination with field inventory data of 2003 to monitor the tree population. They categorised the result as surviving trees (recorded in 1965 and 2003), dead trees (recorded in 1965) or new trees (recorded in 2003) and revealed the change in the tree population.

The study revealed that on an average more than 50 per cent of mature trees disappeared between 1965 and 2003, while almost no new trees (maximum of 3 per cent at one place) came up. This mortality is much higher than the natural mortality of 0.5 per cent. Usually, water and climate are the limiting factors in such areas, but trees' death in the region is influenced by charcoal production, says the study.

According to traditional management customs in the region, green trees should not be felled in any circumstance. But this practice, the researchers say, is fast dying out. "This indicates that the traditional and sustainable indigenous resource management is changing,' says Gidske L Andersen, of the University of Bergen in Norway.

But felling, the study notes, may be an act of "drought-induced despair' with the region facing severe drought. Over time, such a trend will endanger tree populations and resources for the desert community, the study claims.