Moi, your drawing this argument from
one book you read and we discussed
here at CEMB. The evidence from that book about Arab pastoralists wrecking the agriculture of North Africa was based on one research paper which I believe was produced by a graduate student. Whilst I think it is a fascinating study and very believable, I would rather wait for peer review of the idea from other academics in the field before accepting it and posting it all over the internet as fact.
What happens if in a year from now, an expert in the field of climate change or history looks at the theory and tears it apart as nonsense? You will feel pretty dumb for having spouted off about it then. Let's keep calm headed and stick to criticizing Islam based on well substantiated facts and then when these assertions in Scott's book have been supported with stronger evidence, then we can add that to the arsenal of criticisms, but not yet.
Another paper on this idea with some pretty good evidence:
LOWDERMILK, W C. "CONQUEST OF THE LAND THROUGH SEVEN THOUSAND YEARS".
First published as USDA Bulletin No. 99, U.S. Department of Agriculture, Soil Conservation Service, 1939
http://www.wasco.oacd.org/linked/conquest.pdfCheck out pages 15-19
And conclusion:
While the land of North Africa has been seriously damaged, as one can see written on
landscape after landscape, the country is still capable of far greater than its present production.
In Roman times a high degree of conservation of soils and waters was reached with an intensive
culture of orchards and vineyards on the slopes and intensive grain growing in the valleys.
All this depended on efficient conservation and use of the rainfall. We find numerous references
to such practices in the literature of the time. But, as nomads swept in out of the desert, their
extensive and exploitive grazing culture replaced these highly refined measures of land use and
let them fall into disuse and ruin. Erosion was unleashed on its destructive course, and the
capacity of the land to support people was seriously reduced.
The veteran student of North Africa, Professor Gautier, answered my query as to whether
climate of North Africa had changed since Roman times, in the following way: "We have no
evidence to indicate that the climate has changed in an important degree since Roman times, but
the people have changed."
We conclude that the decline of North Africa is due to a change in a people and more especially
to a change in culture and methods of use of land that replaced a highly developed and intensive
agriculture and that allowed erosion to waste away the land and to change the regime of waters.
Note that this is not a new paper, but the author was a renown expert on soil conservation.
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