By 2050, the world is expected to have 9 billion people - as against 6 billion today. The tragedy is that while the biggest sources of biodiversity are in tropical countries, they are the least informed about what they possess, leading to charges of "bio-piracy" against industrial countries which plunder these resources and make extortionate profits on them.

The UN has a Convention on Biological Diversity in place since 1993, which has been signed by most countries, but the protection it offers to countries to protect their natural resources remains largely on paper.

One of the biggest threats to biodiversity is the conversion of forest land to produce more crops. While it is true that the bulk of the food grown by 2050 will come from increasing the productivity of existing farm land, an additional 120 million hectares will have to be brought under the plough in developing countries in the next 30 years, according to the Food and Agriculture Organization. Most of this will be in Latin America and sub-Saharan Africa as half the unused crop land lies in just seven countries - Argentina, Brazil, Bolivia, Colombia, Sudan, Angola and the Democratic Republic of Congo (DRC). Brazil, Angola, Bolivia, Colombia and DRC are among the 25 most biodiverse countries in the world.

The International Union for Conservation of Nature estimates that as many as 350 species of birds, or 3.5 per cent of such fauna, may be extinct in 50 years; birds are a vital indicator of the vitality of the ecosystems.

Another danger is to the marine ecosystem, largely due to reckless over fishing. As is well documented, fishing vessels hunt for the most lucrative species like shrimp. When they trawl the oceans, they regularly dump other species back into the sea, which is an ecological disaster. According to the United Nations Environment Program's World Conservation Monitoring Centre, large species like whales have been hunted to near-extinction. Apart from being polluted from countless sources, the marine ecosystem has to cope with a new hazard, which is the rapid spread of aquaculture. Shrimp is being "farmed" along coasts, which alters the natural balance of these sensitive areas, while a few countries are now also breeding species like tuna - known as "chicken of the sea" - in giant cages submerged in the oceans.

One of the little known, and highly controversial, hazards is due to global warming, which is already changing ecosystems at an alarming rate. The Inter-governmental Panel on Climate Change, which consists of 2,500 scientists from around the world, estimates that the average global surface temperature will be up to 2 degrees Celsius higher in 2050, and atmospheric accumulation of carbon dioxide will be much higher too. As some areas grow hotter while others become cooler or wetter, not to mention the widespread inundation of low-lying coastal areas, flora and fauna are exposed to drastic changes.

A final threat emanates from the genetically modified (GM) crops, which narrow the number of plants being grown on farms. Between 1996 and 1999, for instance, the amount of land devoted to such crops in the US shot up from 1.5 million to over 28 million hectares. At the turn of the century, more than half the soybean and cotton crop, and nearly a third of the corn, was genetically engineered in the US. Apart from shrinking the genetic base, there is the risk of some of these genes escaping into wild relatives of the crops. GM crops have also been known to kill the caterpillars of a species of butterfly, leading to extinction. Elsewhere, the spraying of crops with insecticide, against which the GM crop was genetically protected, has led to the decline of birds there.

Biodiversity offers considerable promise for food, medicine and fiber. Even before the advent of biotechnology, the world was already far too dependent on four or five main crops for food - rice, wheat, corn and potato. The greater the variation in plants available in different ecological niches around the world, the better it is for food security. History is replete with examples - the Irish potato famine in the 19th century is a classic example - where staples were wiped out by disease. On the other hand, there is the example of a tropical plant which can yield a substance 1600 times sweeter than sugar, though scientists have not yet been able to produce it commercially.

Many countries that use traditional systems of medicine know only too well that the forest is a storehouse of invaluable plants which can cure a wide range of ailments. In India, the practice of Ayurveda (a traditional system of medicine) has been very adversely affected by the wanton destruction of forests and other natural habitats. In the US, a quarter of all drugs sold in pharmacies is derived from plants. Another 13 per cent originate from micro-organisms and 3 per cent more from animals. Thus, as much as 40 per cent of pharmaceuticals even in the US are derived from wild plants and animals.

India is an example of a developing country where nearly 7 per cent of the world's crops originated, including rice, mango and pepper. It is blessed with great variations in climate and topography, making it rich in biodiversity. However, the destruction of habitats and severe land degradation is posing major threats to these precious resources. This has led to the loss of traditional agro-systems, which have high crop and livestock diversity. According to the acclaimed National Biodiversity Strategy and Action Plan (NBSAP), the biggest recent threat is the large-scale introduction of exotics and modern cross-breeds, both as far as plants and domesticated animals are concerned. High yielding varieties of wheat, for instance, have replaced indigenous varieties in the Green Revolution areas. Extensive cross-breeding has threatened the existence of local dairy animals, like the Toda buffalo.

NBSAP, drawn up two years ago, recommends that India ought to declare certain areas off-limits for major development projects. It also calls for an ecosystem tax in cities, since urban areas draw water and wood from forests, and a tax on the seed, pharmaceutical, cosmetics and biotechnology industries. Tourists too ought to pay a tax for benefiting from the preservation of natural habitats. It has also proposed more public participation through hearings, rallies and biodiversity festivals, in protecting India's biodiversity.