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As the history of Easter Island suggests, wood has been essential to dozens of human civilizations, and the inability to manage forests sustainably has undermined and destroyed several of them. Today, we have a global forest economy in which the demands of affluent Japanese or Europeans are felt thousands of kilometers away – in tropical Africa, Southeast Asia, and Canada. Since mid – century, the demand for fuel wood has nearly tripled, while paper use has gone up nearly six times. In addition, forestlands are being cleared for slash – and – burn farming by expanding populations and for commercial crop production and livestock grazing. As population pressures intensify in the topics and subtropics, more and more forests are being cleared for agriculture

A combination of logging and clearing land for farming and ranching has weakened forests in many areas to the point where they are vulnerable to fire. A healthy rainforests will not burn. But large segments of the world's rainforests are no longer healthy. During the late summer and fall of 1997, forests burned out of control in Indonesia. For month, heavy smoke filled the air in the region, causing millions of people to become ill. Some 1,100 airline flights were canceled. Earnings from tourism dropped precipitously.

Although the fires in Indonesia captured the news headlines, there was even more extensive burning in the Amazon, which received much less attention because it was more remote.

And in the spring of 1998, forests began to burn out of control in southern Mexico. The nearby state of Texas had several dangerous air alerts as the smoke moved northward. At times, it drifted as far north as Chicago. In early summer 1998, fires also started burning out of control in Florida. Even with personnel and equipment from some 23 states brought in to help, efforts to tame the fires failed. One entire country was evacuated along with parts of several others – and this in a country that probably has the most sophisticated fire – fighting equipment in the world.

No one could have of the burning around the world during this 12 – month span. But in retrospect, there was a human influence in each of these situations. A combination of forests weakened by the forces just cited, EL Nino – related droughts, and in some cases, as in Florida, record high temperatures contributed to this wholesale burning.

Fisheries actually preceded agriculture as a source of food, but ours is the first generation to reach – and perhaps exceed – the sustainable yield of oceanic fisheries. In fact, in just the last half century the oceanic fish catch increased nearly five times, doubling seafood availability per person for the world as a whole. Marine biologists doubt, however, that the oceans can sustain a catch much above the 95 million tons of the last few years.

According to the U. N. Food and Agriculture Organization, 11 of the world`s 15 most important fishing areas and 70 percent of the major fish species are either fully or overexploited. The welfare of more than 200 million people around the world who depend on fishing for their income and food security is threatened.

If the biologists are right, then the decline in seafood catch per person, which started in 1989, will persist for as long as population growth continues. Those born shortly before 1950 have enjoyed a doubling in seafood availability per person, whereas those born in recent years can expect to see a halving of the catch per person during their lifetimes. The beginning of the new millenium marks the turning point in oceanic fisheries, a shift from abundance to one where preferred species become scarce, seafood prices rise, and the conflicts among countries for access to fisheries multiply.

Although the yield data are not as those for oceanic fisheries, the world`s range lands cover roughly twice the area of croplands, supplying most of the beef and mutton eaten worldwide. Unfortunately, as with fisheries, overgrazing is now the rule, not the exception. Sustaining future yields of meat, and in some cases milk as well, and providing livelihoods for ever – growing pastoralist populations will put even more pressure on already deteriorating range lands. Yet another of our basic support systems is being overwhelmed by continuously expanding human needs.

Biodiversity and Climate Change

Perhaps the best single indicator of the Eart`s health is the declining number of species with which we share the planet. Throughout most of the evolutionary history of life, the number of plant and animal species has gradually increased, giving us the extraordinarily rich diversity of life today. Unfortunately, we are now in the early stages of the greatest decimation of plant and animal life in 65 million years.