Biology Reference
In-Depth Information
woodland plants. Based on research in the Park by the Trollopes and others, it was realized
that the problem was the regular man made fires were set when there was little wind, less dead
vegetation, and under controlled conditions so the fires were not as intense as natural
lightening related fires, or for that matter, those set by illegal Mozambique immigrants trying to
escape the civil war and poverty. Intense fires burn also tree canopies that would not be
damaged as much by man-made fires. Hence more intensive fires are now set on an adaptive
cycle based on rain and vegetation and allowance for naturally set fires. It has also been found
that late spring and winter fires result in the best grass production. Intensity of fire does not
affect damage to the grass root sward which obviously is underground. Once woodlands take
over grasslands it is difficult to reverse since there is typically more moisture and resistance to
fires and only severe droughts will bring woodland overpopulation back into control for the
production of grass. The fires of Yellowstone clearly demonstrated much of the above. Sally
Archibald from the CSIR in South Africa has been analyzing fires in Africa and has noted the
balance between forest and savanna is affected by fire and the concern is that if this balance
changes, animals will run into trouble as the vegetation changes because the animals are not
free to move as they once were able to since man made borders not restrict migration to better
pastures. This also has relevance because the upset in the balance between woodlands and
savanna grasslands was probably responsible for the die off several Southern species 9,500
years ago when the Cape horse, giant hartebeest, and giant buffalo (Pelorovis antiquus, 2200
lbs., maybe up to 4,000 lbs., 10 feet - 120” wide horns, twice modern buffalo, and wider than
Texas Longhorn of 84” - the mount above the Stelzig store entrance in Terminal C in Houston
must be close to that record and the manager believed it was 9 feet wide) became extinct. Over
successful hunting, as is possibly the case in North America, does not appear to have been a
factor. There has also been found on satellite surveys using NOAA MODIS monitoring of 823
tropical and subtropical parks that there is a correlation between fires within parks and the
level of corruption, poverty, and lack of control. This is because fires indicate wood
extraction from parks for charcoal production and clearing for agriculture. Normally fires are
uncommon in tropical forests because of the high moisture content.
As we travel on the road south east to Mazunga we pass villages, some of them remnants of
a more prosperous past, at least for whites. At one point some 300,000 whites lived in the then
named Rhodesia, but now only some 10,000 remain, probably 7,000 of them in Harare,
formerly called Salisbury. The villages are now more like third world country villages with
open drains clogged with trash, unkempt gardens with growing weeds, unfinished buildings,
sometimes broken glass if they were built far enough before cash ran out. Many also had
barbed wire fences and window grates for security and unleashed dogs and half naked children
on the potholed, once paved streets. A long the rural parts of the road are rusted signs and
broken gates to farms or ranches with faded European names of past owners on askew name
places.
The fences are torn down and telephone and electricity wires dangle between askance
poles. Where there were game fences to keep out wild animals from rural areas, these were
often broken down.
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