Sociology (the study of people and society)
The answer is Agriculture.
Most of Australia is dry and sunny, there are many desserts and dry areas, unless of course you live in Tasmania like myself where is usually pretty wet. Although we do have some hot weather (hot being 25 degrees celcius) which isn't nearly as hot as is it is on the mainland where it can get up to close to 50 degrees celcius!!
Producing and growing crops like soy, weaken the dirt, making it more vulnerable to crumble off and clog waterways or pipes.
"In republics, citizens have less direct control over government. ... (c) Why do some people hold that the United States is more properly called a republic rather than a democracy? In a Democracy there is no need for a Constitution, since the majority can simply change Law at a whim."
From google
