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	Issue 8

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Cattle, sheep, and the arid heart
There are too many cattle in Central Australia just now. About half a million are grazing on properties in the Alice Springs region — an all-time high. They have bred up during the remarkably wet last 3 years and, because cattle prices are low, property-owners are holding onto their stock in the hope that markets will improve. But such wet years can't go on much longer — they never have before. What happens then?
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Harnessing heat from the sun
The energy the world needs has always been supplied by the sun. The fossil fuels that industrial society consumes in such great quantities — oil, coal, and natural gas — supply energy from the sun gathered by green plants over millions of years and stored. And, of course, solar energy lights and warms the earth and sustains the vegetation that the rest of life depends on for food.
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What happens to animals in a bushfire? Scientists have made very few studies of the effects of summer bushfires on Australia's forest animals — mainly because it is extremely difficult to set up experiments. Download Article

Phosphorus, and feeding the world Without phosphate fertilizers, the world could not grow enough food to support its present 4000 million people, let alone the 7000 million expected by the end of the century. Download Article

Helping to work out where to build The planners of the Albury-Wodonga growth centre expect its population to increase from 50 000 to 300 000 by the end of the century. Their task is to work out the best way to cope with the influx. Download Article

Ozone falls as the winds weaken The ozone content of the stratosphere above Australia seems to have decreased slightly over the past few years. But the evidence doesn't point to supersonic jet exhausts, spray-can gases, or any other pollutants as the cause. The decrease appears to be due to a reduction — probably temporary — in high-altitude wind strengths. Download Article

Living with wildlife on the farm When is a pest not a pest? Some cynics might answer‘when it s been investigated by the CSIRO Division of Wildlife search’. Such an answer would be unfair. Even so, it does contain a grain of truth. On closer study, a number of animals and birds have turned out to be not the major agricultural posts they were cracked up to be. Download Article

A lesson from rusty match tress Poplars are decorative trees, and rows of them make good wind breaks. Perhaps less-well known is the fact that most of the match-sticks sold in Australia are poplar wood. Download Article