Normally, the deserts shift somewhat, and over millions upon millions of years, they can spread far. However, what we are seeing is rapid desertification, not the glacerlike process that allows animals to adapt. Take the 'Dust Bowl', a clear result of overgrazing leading to desertification.
are you seriously that lost? where did you get that load of absolute b.s. from, a dr. suess science book? the dust bowl era of the u.s. was caused by poor farming practices and an extended drought, not over grazing...even wikipedia should have that right...and it absolutely did not nor is currently leading to desertification...in case you missed it with your genius, all of the areas affected have been fertile farmland for the last 60+ years.
Unpolluted rain has a pH of 5.7, because of volcanic eruptions and other releases of CO2. However, the acid rain you hear about is many hundreds of times that level. Below 5 pH, fish eggs will not hatch, and even lower levels will kill adult fish.
However, these questions are off topic.
I did check my facts, and I found that not all sewage can be treated this way. However, upon closer examination, I've noticed that it also depends on the amount of toxins (such as heavy metals and chemicals with names that professional linguists balk at) from industry that are included in the sewage. In some cases, it is minimal, in other cases (such as industrial farming) the amount is astonishing. It's not a silver bullet, but it'll help a great deal.
-Penguin
again, more dr. seuss science...acid rain, acid snow and acid fog are nowhere near acidic to the tune of "hundreds of times" the level of rain you would find in the most remote unpopulated region on the planet...heavily industrialized areas with dense population tend to have higher levels of acidic atmospheric moisture than non industrialized areas as low as approximately ph 2.0 at some point in history (i think it was in 70s)...but right now the average is believed to be around 4.6. volcanic rifts in the ocean floor with sea life around them are far more acidic than anything humans have done after 160 years of rapidly increasing industrialization...parts of the amazon river have a ph of around 4.5-4.7 and there are plenty of fish species that live and breed in it...there goes your theory of fish habitation in acidic water.
you also need to learn the difference between "industrial wastewater" and "sewage"...although sewage can contain compounds found in industrial waste water, it is not the same and it is treated differently...at least here in the u.s. it is...and remember that the next time you see someone tossing drain cleaner in a clogged sink. the way you associated industrial farming with industrial waste treatment is astoundingly...wrong. the waste from industrial farming does not generally get treated nor mixed in with domestic or industrial waste treatment...and that's the issue environmentalists have with the industry. unfortunately the chemicals used in and around industrial farms finds its way into the ground, rivers and streams...it's taken decades of research to fully understand the environmental effects and it doesn't appear that much will change in the future.
