Please, help me to answer this question

Omar,

I am reminded of two different occurances where we
lsot alot of vegetation. The first is the great
dustbowl time in the United States in the 1930s. This
saw huge dust storms range across the midwest ripping
the topsoil off everything. A good picture and blurb
of it can be found here:
http://en.wikipedia.org/wiki/Dust_Bowl

The second one I can think of happened in Beijing
during the 1970s. During this time, the Chinese were
trying to eradicate the mosquito population by
destroying their habitat. They went around and
destroyed much of the grass and many trees. This in
turn caused the desert to get closer to beijing and
the air in the 80s and 90s had much dust in it. They
were fixing this in the late 90s when i was last there
by planting grass everywhere and it has greatly
reduced the amount of dust in the air.

You may wish to do some research into the process
of Desertification for more look at impacts in which
vegetative areas were destroyed. Good leaping point
is http://en.wikipedia.org/wiki/Desertification.

- Ryan Z

--- Lucio de Souza Coelho wrote: