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Biodiversity

A. It seems biodiversity has become a buzzword beloved of politicians, conservationists, protesters and scientists alike. But what exactly is it? The Convention on Biological Diversity, an international agreement to conserve and share the planet’s biological riches, provides a good working definition: biodiversity comprises every form of life, from the smallest microbe to the largest animal or plant, the genes that give them their specific characteristics and the ecosystems of which they are apart.

B. In October, the World Conservation Union (also known as the IUCN) published its updated Red List of Threatened Species, a roll call of 11,167 creatures facing extinction – 121 more than when the list was last published in 2000. But the new figures almost certainly underestimate the crisis. Some 1.2 million species of animals and 270,000 species of plants have been classified, but the well-being of only a fraction has been assessed. The resources are simply not available. The RJCN reports that 5714 plants are threatened, for example, but admits that only 4 per cent of known plants have been assessed. And, of course, there are thousands of species that we have yet to discover. Many of these could also be facing extinction.

C. It is important to develop a picture of the diversity of life on Earth now so that comparisons can be made in the future and trends identified. But it isn’t necessary to observe every single type of organism in an area to get a snapshot of the health of the ecosystem. In many habitats, there are species that are particularly susceptible to shifting conditions, and these can be used as indicator species.

D. In the media, it is usually large, charismatic animals such as pandas, elephants, tigers and whales that get all the attention when the loss of biodiversity is discussed. However, animals or plants far lower down the food chain are often the ones vital for preserving habitats – in the process saving the skins of those more glamorous species. These are known as keystone species.

E. By sudying the complex feeding relationships within habitats, species can be identified that have a particularly important impact on the environment. For example, the members of the fig family are the staple food for hundreds of different species in many different countries, so important that scientists sometimes call figs “jungle burgers”. A whole range of animals, from tiny insects to birds and large mammals, feed on everything from the tree’s bark and leaves to its flowers and fruits. Many fig species have very specific pollinators. There are several dozen species of fig trees in Costa Rica, and a different type of wasp has evolved to pollinate each one. Chris Lyle of the Natural History Museum in London – who is also involved in the Global Taxonomy Initiative of the Convention on Biological Diversity – points out that if fig trees are affected by global warming, pollution, disease or any other catastrophe, the loss of biodiversity will be enormous.

F. Similarly, sea otters play a major role in the survival of giant kelp forests along the coasts of California and Alaska. These “marine rainforests” provide a home for a wide range of other species. The kelp itself is the main food of purple and red sea urchins and in turn, the urchins are eaten by predators, particularly sea otters. They detach an urchin from the seabed then float to the surface and lie on their backs with the urchin shell on their tummy, smashing it open with a stone before eating the contents. Urchins that are not eaten tend to spend their time in rock crevices to avoid the predators. This allows the kelp to grow – and it can grow many centimeters in a day. As the forests form, bits of kelp break off and fall to the bottom to provide food for the urchins in their crevices. The sea otters thrive hunting for sea urchins in the kelp, and many other fish and invertebrates live among the fronds. The problems start when the sea otter population declines. As large predators they are vulnerable – their numbers are relatively small so disease or human hunters can wipe them out. The result is that the sea urchin population grows unchecked and they roam the seafloor eating young kelp fronds. This tends to keep the kelp very short and stops forests developing, which has a huge impact on biodiversity.

G. Conversely, keystone species can also make dangerous alien species: they can wreak havoc if they end up in the wrong ecosystem. The cactus moth, whose caterpillar is a voracious eater of prickly pear was introduced to Australia to control the rampant cacti. It was so successful that someone thought it would be a good idea to introduce it to the Caribbean islands that had the same problem. It solved the cactus menace, but unfortunately, some of the moths have now reached the US mainland – borne on winds and in tourists’ luggage – where they are devastating the native cactus populations of Florida.

H. Organizations like the Convention on Biological Diversity work with groups such as the UN and with governments and scientists to raise awareness and fund research. A number of major international meetings – including the World Summit on Sustainable Development in Johannesburg this year – have set targets for governments around the world to slow the loss of biodiversity. And the CITES meeting in Santiago last month added several more names to its list of endangered species for which trade is controlled. Of course, these agreements will prove of limited value if some countries refuse to implement them.

I. There is cause for optimism, however. There seems to be a growing understanding of the need for sustainable agriculture and sustainable tourism to conserve biodiversity. Problems such as illegal logging are being tackled through sustainable forestry programs, with the emphasis on minimizing the use of rainforest hardwoods in the developed world and on rigorous replanting of whatever trees are harvested. CITES is playing its part by controlling trade in wood from endangered tree species. In the same way, sustainable farming techniques that minimize environmental damage and avoid monoculture.

J. Action at a national level often means investing in public education and awareness. Getting people like you and me involved can be very effective. Australia and many European countries are becoming increasingly efficient at recycling much of their domestic waste, for example, preserving natural resources and reducing the use of fossil fuels. This, in turn, has a direct effect on biodiversity by minimizing pollution, and an indirect effect by reducing the number of greenhouse gases emitted from incinerators and landfill sites. Preserving ecosystems intact for future generations to enjoy is obviously important, but biodiversity is not some kind of optional extra. Variety may be “the spice of life”, but biological variety is also our life-support system.

Sunset for the Oil Business

The world is about to run out of oil. Or perhaps not. It depends on who you believe…

A. Members of the Department Analysis Centre (ODAC) recently met in London and presented technical data that support their grim forecast that the world is perilously close to running out of oil. Leading lights of this moment, including the geologist Colin Campbell, rejected rival views presented by the American geological survey and the international energy agency that contradicted their findings. Dr Campbell even decried the amazing display of ignorance, denial, and obfuscation by government, industry, and academics on this topic.

B. So is the oil really running out? The answer is easy: Yes. Nobody seriously disputes the notion that oil is, for all practical purposes, a non-renewable resource that will run out someday, be that years or decades away. The harder question is determining when precisely oil will begin to get scarce. And answering that question involves scaling Hubbert’s peak.

C. M. King Hubbert, a Shell geologist of legendary status among depletion experts, forecast in 1956 that oil production in the United States would peak in the early 1970s and then slowly decline, in something resembling a bell-shaped curve. At the time, his forecast was controversial, and many rubbished it. After 1970, however, empirical evidence proved him correct: oil production in America did indeed peak and has been in decline ever since.

D. Dr Hubbert’s analysis drew on the observation that oil production in a new area typically rises quickly at first, as the easiest and cheapest reserves are tapped. Over time, reservoirs age and go into decline, and so lifting oil becomes more expensive. Oil from that area then becomes less competitive in relation to other fuels, or to oil from other areas. As a result, production slows down and usually tapers off and declines. That, he argued, made for a bell-shaped curve.

E. His successful prediction has emboldened a new generation of geologists to apply his methodology on a global scale. Chief among them are the experts at ODAC, who worry that the global peak in production will come in the next decade. Dr. Campbell used to argue that the peak should have come already; he now thinks it is just around the comer. A heavyweight has now joined this gloomy chorus. Kenneth Deffeyes of Princeton University argues in a lively new book (“The View from Hubbert’s Peak”) that global oil production could peak as soon as 2004.

F. That sharply contradicts mainstream thinking. America’s Geological Survey prepared an exhaustive study of oil depletion last year (in part to rebut Dr. Campbell’s arguments) that put the peak of production some decades off. The IEA has just weighed in with its new “World Energy Outlook”, which foresees enough oil to comfortably meet the demand to 2020 from remaining reserves. Rene Dahan, one of ExxonMobil’s top managers, goes further: with an assurance characteristic of the world’s largest energy company, he insists that the world will be awash in oil for another 70 years.

G. Who is right? In making sense of these wildly opposing views, it is useful to look back at the pitiful history of oil forecasting. Doomsters have been predicting dry wells since the 1970s, but so far the oil is still gushing. Nearly all the predictions for 2000 made after the 1970s oil shocks were far too pessimistic. America’s Department of Energy thought that oil would reach $150 a barrel (at 2000 prices); even Exxon predicted a price of $ 100.

H. Michael Lynch of DRI-WEFA, an economic consultancy, is one of the few oil forecasters who has got things generally right. In a new paper, Dr. Lynch analyses those historical forecasts. He finds evidence of both bias and recurring errors, which suggests that methodological mistakes (rather than just poor data) were the problem. In particular, he faults forecasters who used Hubbert-style analysis for relying on fixed estimates of how much “ultimately recoverable” oil there really is below ground, in the industry’s jargon: that figure, he insists, is actually a dynamic one, as improvements in infrastructure, knowledge, and technology raise the amount of oil which is recoverable.

I. That points to what will probably determine whether the pessimists or the optimists are right: technological innovation. The first camp tends to be dismissive of claims of forthcoming technological revolutions in such areas as deep-water drilling and enhanced recovery. Dr. Deffeyes captures this end-of-technology mindset well. He argues that because the industry has already spent billions on technology development, it makes it difficult to ask today for new technology, as most of the wheels have already been invented.

J. Yet techno-optimists argue that the technological revolution in oil has only just begun. Average recovery rates (how much of the known oil in a reservoir can actually be brought to the surface) are still only around 30-35%. Industry optimists believe that new techniques on the drawing board today could lift that figure to 50-60% within a decade.

K. Given the industry’s astonishing track record of innovation, it may be foolish to bet against it. That is the result of adversity: the nationalizations of the 1970s forced Big Oil to develop reserves in expensive, inaccessible places such as the North Sea and Alaska, undermining Dr. Hubbert’s assumption that cheap reserves are developed first. The resulting upstream investments have driven down the cost of finding and developing wells over the last two decades from over $20 a barrel to around $6 a barrel. The cost of producing oil has fallen by half, to under $4 a barrel.

L. Such miracles will not come cheap, however, since much of the world’s oil is now produced in ageing fields that are rapidly declining. The IEA concludes that global oil production need not peak in the next two decades if the necessary investments are made. So how much is necessary? If oil companies are to replace the output lost at those ageing fields and meet the world’s ever-rising demand for oil, the agency reckons they must invest $ 1 trillion in non-OPEC countries over the next decade alone. That’s quite a figure.