AS the Indian prophecy goes:

"Only after the last tree has been cut

Only after the last river has been poisoned

Only after the last fish has been caught

Only then you will find

That money can not be eaten."

The dire prophecy should galvanise us into action-oriented programmes to tackle the problems relating to environment that we face today. We must remember that many past societies collapsed partly because of their failure to solve problems similar to those that we face now -- especially deforestation, water management, top soil loss, and climate change.

For more than 40 years, the earth has been sending distress signals. We have responded by holding seminars and passing environmental laws on Earth Day and World Environment Day. All the while, the decline of the earth's ecosystem has continued unabated.

Thomas Lovejoy of the Smithsonian Institute said: "Amazon is a library of the world's life sciences, the world's greatest pharmaceutical laboratory and flywheel of climate." Such may be said of the Sundarbans and the hill forests of Chittagong as well. Forests in our country or in Brazil are untapped storehouses of evolutionary achievement that will prove increasingly valuable to mankind as they yield their secrets.

However, biologists see biodiversity vanishing before their eyes because of deforestation, which has devastating effects on climate change and on natural processes upon which the earth's delicate balance depends.

Turning forests into isolated patches, logging, or setting fire to trees (as has happened in Brazil and Indonesia), threaten biodiversity. While covering only 6% of the earth's land surface, the world's forests are decreasing by 58,560 sq.miles each year. With other rich environments under similar assault, including coral reefs (two-thirds degraded) and salt marshes and mangrove swamps (half eliminated or radically altered), the extinction rate of species is rising everywhere.

Humanity's food supply comes from a narrow sliver of biodiversity. Throughout history, people have gathered or cultivated about 7,000 plant species for food. Today, only 20 species provide 90 % of the world's food, with maize, wheat and rice supplying more than half.

Natural pharmaceuticals offered by biodiversity are also underutilised. The biochemistry of the vast majority of species is an unfathomable reservoir of potentially more effective substances. These species have devised myriad ways to combat microbes and cancer causing runaway cells. As the enhancement of agriculture and medicine become the mainstay for the survival of the exploding population in the world, there is hardly an alternative to conserving the forests. Furthermore, the biosphere gives us renewed soil, energy, clean water, and the very air we breathe, all free of charge. The more species that compose wild communities, the more stable and resilient the planet becomes as a whole.

The forest functions like a delicately balanced organism that recycles most of its nutrients and much of its moisture. Wisps of steam float as water evaporates off the upper leaves, cooling the trees as they collect the sunlight. Air currents over the forests gather this evaporation into clouds, which return the moisture to the system as rain. Dead animals and vegetation decompose quickly and the resulting nutrients move rapidly from the soil back to the growing plants. The forest is such an efficient recycler that virtually no decaying matter seeps into neighbouring rivers.

The rain forest is an almost self-sustaining system that thrives indefinitely. But when stripped of trees, the land becomes inhospitable. Most of the forest soil becomes nutrient-poor and ill-suited for agriculture. The rain forest or the mangrove forest has an uncanny capacity to flourish in soils that elsewhere would not even support weeds. Henry Ford tried twice to carve rubber empires out of the rain forest in 1920 and 1930s. But when the protective canopy was cut down the rubber trees withered under the assault of sun, rain and pests. The story is the same here in our country.

Because of the huge volume of clouds it generates, the forest system plays a major role in the way the sun's heat is distributed around the globe. The Amazon alone stores about 75 billion tons of carbon in its trees. Since the air is already dangerously overburdened with carbon dioxide the destruction of either the Amazon or the Sundarbans could magnify the trapping of heat by atmospheric carbon dioxide.

The world needs lots of trees to store the carbon produced by a growing population and industrialisation. Forests are carbon dumps. Trees extract carbon dioxide from the atmosphere, emit the oxygen and store the carbon in their wood, leaves, roots and surrounding soil. Climate and rainfall make certain areas better suited than others to the creation and maintenance of large standing stores of carbon. It is only logical that the countries that control forest areas will begin to demand rent in one form or another for the service which they provide to the rest of the world.

Most people who live in and around forests are poor, and their population growth continues. Whether it is the Brazilian, Philippines, African, Indonesian or coastal zone of Bangladesh covering the Sundarbans, we must concede that most people actually carrying out the destruction are obeying the first rule of any living being -- to survive. To preserve an environment, whether it be wetland or forest, there must be an acceptable and rising level of economic well-being of the humans who live in and around it.

Environmentalism requires restraint. Poor people lack restraint. Without some economic surplus there will never be meaningful conservation. So economic progress or sustainable development in our part of the world is not an option that we can postpone at this crucial hour of our imperiled environment. A crash programme must be undertaken to raise the living standards of the people living in and around forests along with measures to check population growth. It has to be recognised that the preservation of the world's forests is a matter of international security.

Government agencies claim that Bangladesh has 2.52 million hectares of forest land, though studies by different agencies say it is 1.44 million hectares. The Bangladesh part of the Sundarbans spans about 6,000 sq km, including a water area of 1,700 sq km.

Shrimp culture, logging, setting up of brick kilns in agricultural land and forested areas, and rampant insecticide use, are some of the major causes of forest destruction. Brick kilns that use firewood puff away 2.4 crore trees every year -- covering about 96,000 acres of land -- as a report published in The Daily Star on June 5 shows. Shrimp cultivation increases water salinity, inhibiting growth of trees and destroying croplands that depend on fresh water. Loggers are cutting down trees deep in the forests, destroying the very resources that support human life. Consequently, the forest areas and the life forms that depend on them are disappearing at a faster rate than ever before.

Trees are the most essential bounties of nature contributing to the sustenance of life on earth. To industrialised countries trees are a treasure trove of biodiversity and green house gas sinks. To developing nations, forests are resources ripe for exploitation -- a potential farm land, a free source of fuel and a storehouse of expensive woods.

There is a close link between economic growth, human development and good management of natural resources, mainly water bodies and forests. Unfortunately, socio-economic development is threatened by environmental degradation through polluted water and extinction of forests. Researchers estimate if the current rate of pollution of land and water followed by habitat destruction were to continue, our descendants will inherit a biologically impoverished and homogenised world.

The writer is a columnist of The Daily Star.

E-mail: aukhandk@gmail.com