Market economies are based on market forces like supply and demand. Mixed economies fall in the middle of market and command economies (where economic choices are governed by some central entity usually the government). The former Soviet Union (USSR) is an example of a command economy where economic choices (what to buy, sell and produce) where made by the government. If Australia is becoming more of a market economy and less of a mixed economy, fewer decisions are made by the government. Here's a diagram of two major types of economies:
Command Economy <-------------- Mixed Economy --------> Market Economy
(Government makes the decisions) (A little of both) (Individuals decide)
Although global human impact (global warming) is not to be ignored, this is mainly because of the El Nino in the <span>central and eastern equatorial Pacific Ocean.
If you're in the Eastern USA, its messing with the jet stream the high/low pressure ridges, causing the cold front to not be within the Northeastern USA area this year.
If you're in other areas far enough I don't know, global warming?
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Answer:
because it begins where there is no soil. It can take several hundred to several thousand years to produce fertile soil naturally. The first pioneer species to colonize the bare rock will probably be bacteria and lichens, which can live without the soil.