Mother Earth Takes a Battering New Scientist 6 Sept 97
AN Australian scientist has presented the first report card of a massive intemational scientific undertaking called the Global Change and Terrestrial Ecosystems project. The project, with an annual budget of US$44 million, pulls together ecological and environmental research done at the local level so that a picture of the state of the planet can be built up. The report of the project's first six years of work was presented last month by Brian Walker, head of the CSIRO Division of Wildlife and Ecology, who used a conference of the Ecological Society of America in New Mexico as his forum. Walker is a former chairman of the project's scientific steering committee which vets the research and coordinates the exercise. Walker's report was only a summary-the full version is about to be published by Cambridge University Press-but the summary had plenty of bite. The expected population increase of about a billion people a decade will cause increasing demand for food and fibre, Walker said. To meet the expected needs crop yields will need to increase consistently by over 2 per cent every year. That means more intense agriculture in areas already cropped. It will also require conversion of forests and grasslands into new farms Many of these will be on marginal land which is likely to erode and be degraded. The long-term consequences of these changes are profound, he said. We will lose many species as forests are converted to cropland. This will have consequences for ecosystem functioning that are as yet unknown. Problems like die-back, already a serious problem in Australia because of its impact on eucalyptus trees, are likely to worsen. Old-growth areas, with their ecological complexity of flora and fauna, will decline. The biosphere in general will be weedier and structurally more simple. All this means that our biological systems will be less able to cope with changing conditions-bad news now that an altered global climate seems inevitable. Can anything meaningful be done to prevent these changes or at least lessen their impact? The driving force is increasing population. Finding a socially acceptable way to stabilise the human population is an urgent task. In this context it was interesting last weekend to hear some calculations done by former senator John Coulter who was speaking in Sydney at conference called Stabilising Australia's Population. Population growth is usually seen as an economic stimulus. But Coulter showed that the two Australian states with the lowest rates of population growth, South Australia and Victoria, are the two with the highest rates of increase in economic output per head. The two with the highest rates Of population growth, Queensland and Westem Australia, have by far the lowest rates of increase in wealth per head.