Biodiversity

Biodiversity is the variety of species, their genetic make-up, and the natural communities in which they occur. It refers to the wide range of organisms—plants and animals — that exist within any given geographical region. That region may consist of a plot of land no more than a few square meters or yards, a whole continent, or the entire planet. In other words it is all about the number, variety and variability of living beings and how these change from one location to another and over time. Biodiversity does not just include the rich variety of species of living things but also the rich variety of types found within species. Thus it includes diversity within species (genetic diversity), between species (species diversity), and between ecosystems (ecosystem diversity).

Why should I be aware of this?

• Biodiversity is the basis of the multiple benefits provided by ecosystems to humans. It is important in all ecosystems, not only in those that are "natural" such as national parks or natural preserves, but also in those that are managed by humans, such as farms and plantations, and even urban parks.
• Concerns about biodiversity are relatively new. Only during the last quarter of the twentieth century did scientists begin to appreciate the vast number of organisms found on earth and the complex ways in which they interact with each other and with their environments. Biologists have now discovered and named about 1.7 million distinct species of plants and animals. As many as 50 million species, however, are thought to exist.

All about biodiversity

Biodiversity plays a major role in areas like air and water quality, global climate and scientific efforts to produce higher yielding, pest-resistant crops.

• Makes species weaker -- The reduction in biodiversity affects the ability of various communities to resist or recover from environmental change, including long-term climatic change to change.
• Increases resistance -- The numerous strains of rice, for instance, increase the probability that some strains will have the means to resist common plagues.
• Affect food supply -- The extinction of plants can affect food crops in at least two ways:
  • The extinction of the wild relatives of cultivated crops, wipes a potential source of genes for future breeding
  • It reduces the number of strains within cultivated species
• Medicine -- About 25 percent of commercially manufactured medicines are derived from plants, and new medicinal plants continue to be found. The reduction in plant varieties will have an adverse impact on the availability of several medicines.

The huge growth in human population over the past century, now totaling some 6.5 billion, is responsible for colonization of previously remote wilderness areas and for providing a market for the decimation of ancient forests and rare wildlife for commercial purposes. Land is being cleared for grazing livestock and farming, while mining, industry, corporate logging and other development are obliterating species throughout the world. Forests have the largest number of threatened species of any habitat, although the oceans have scarcely been explored for biodiversity. Tropical forests throughout the world harbour about half the world's plants and animals on only 7 percent of the planet's land area.

This phenomenon is not just limited to apples but is true for pear, wheat and most other fruits, vegetables and grains. Activities such as farming, logging and commercial fishing are endangering plants, animals and entire ecosystems at much higher rates than ever before in recorded history, according to a report issued by the United Nations Environment Program. economic markets continue to underestimate the role Early in the 20th century, for example, probably over 100,000 folk varieties of rice were cultivated in Asia, with at least 30,000 in India alone. Now 75 percent of India's crop consists of just ten varieties. Sri Lanka's 2,000 rice strains have been all but replaced by 5. Mexico, the cradle of corn domestication, cultivates just 20 percent of the varieties that were found there in the 1930's.

Importance of biodiversity

Scientists say that diversity is just as vital to the plants we grow for food as it is to those growing wild in the forests, jungles, and grasslands of the world. Diversity within a species matters too. Diversity

The reduction in the earth's biodiversity can have an adverse effect on our food supply. first, by wiping out the wild relatives of cultivated crops, a potential source of genes for future breeding, and second, by reducing the number of strains within cultivated species.

But more than just food is at stake. About 25 percent of commercially manufactured medicines are derived from plants, and new medicinal plants continue to be found.

Hub of biodiversity

Although life exists almost everywhere on the earth, certain ecosystems such as the tropical forests and coral reefs harbour the greatest diversity of species. A single tree in Peru was found to have 43 species of ants, a number equal to all the species of ants found in the British Isles. Remnants of Brazil's Atlantic Forest have been found to harbour the greatest diversity of trees in the world: 476 species in a plot of only 2.5 acres. By contrast, a plot of similar size in a North American temperate forest has fewer than 80 species of trees. This forest which once covered millions of square miles along the southern coast and well inland has been reduced by 92 percent. Destruction of these hubs of biodiversity, even to a small extent has far reaching impact on our ecosystems.

Danger to biodiversity

As a result of extensive deforestation, especially in tropical countries, many studies of forest fragmentation and its effects on biological diversity are taking place, finding that losses of even a few species can result in major ecological damage.

Natural changes tend to occur at a gradual pace, usually causing only a slight impact on individual species. However, when changes occur at a fast pace, there is little or no time for individual species to react and adjust to new circumstances. This can create disastrous results.

Habitat destruction

Rapid habitat loss is the primary cause of species becoming endangered. The burgeoning human population has cleared forests to live and farm. While activities such as hunting, overfishing, cutting trees and clearing forests have had a direct impact on biodiversity of the planet, pollution, global warming, release of greenhouse gases have had a damaging impact on hubs of biodiversity such as the coral reefs. Clearing of rainforests has resulted in loss of microbes in soils that formerly supported tropical forests.

Introduction of Exotic Species

Native species, comprising plants and animals that inhabit a particular biological landscape for a lengthy period of time, are well adapted to their local environment and are accustomed to the presence of other native species within the same general habitat. When exotic species, are introduced into new environments by way of human activities, either intentionally or accidentally, they sometimes prey on the native species. Species have been introduced to environments all over the world, and the most destructive effects have occurred on islands.

Overexplotation

Due to the trade in animal parts, many species continue to suffer high rates of exploitation. Unrestricted whaling during the 20th century is an example of overexploitation, and the whaling industry brought many species of whales to extremely low population sizes. Even today, there are demands for items such as rhino horns and tiger bones in several areas of Asia. The demand for ivory had led to indiscrminate poaching and endangered elephant population in several parts of the world.

Other factors

If a species does not have the natural genetic protection against particular pathogens, an introduced disease can have severe effects on its local population. Domestic animals often transmit the diseases that affect wild populations -- and here again human activities is the root cause of this.

Steps to save biodiversity

The 2010 biodiversity target stresses that at least 10% of all ecosystem types should be under protection to maintain nature and natural landscapes. It warns against overfishing damaging farming practices the usage of pesticides and fertiliser. It stresses on the need to promote organic agriculture practices. Roads, factories and housing destroy habitats for animals and plants. If urban and rural development continues to ignore nature, our surroundings will be dominated by concrete and pollution.

Since the adoption of the Convention on Biological Diversity in 1992, most countries have developed National Biodiversity Strategies and Action Plans.

CopperBytes

• The rapid disappearance of species was ranked as one of the planet's gravest environmental worries, surpassing pollution, global warming and the thinning of the ozone layer, according to the survey of 400 scientists commissioned by New York's American Museum of Natural History.
• A report issued by the United Nations Environment Programme concludes that at least 4,000 plants and 5,400 animals are threatened with extinction. The report observes that species have recently become extinct at 50 to 100 times the average expected natural rate.
• Only some 1.75 million, or about 13 percent of the 13 million to 14 million species on earth, have been scientifically identified.
• About 88 percent of the 2,683 varieties once grown are now extinct. And when it comes to vegetables, the numbers are even grimmer. Diversity within the various kinds of vegetables grown in the United States has been slashed by 97 percent in less than 80 years.

90 degrees

• Human beings are responsible for causing the greatest mass extinction of species since the extinction of the dinosaurs 65 million years ago. If present trends continue one half of all species of life on earth will be extinct in less than 100 years, as a result of habitat destruction, pollution, invasive species, and climate change.
• According to the World Conservation Union, of some 18,000 species of plants and animals investigated, more than 11,000 face extinction. In places such as Indonesia, Malaysia, and Latin America, where great stretches of forest have been cleared for plantations, many species have become threatened or extinct.

Additional Information

• All National Biodiversity Strategies and Action Plans can be found at Convention on biodivrsity

See Also

• Trawling
• Threatened species
• Multiple cropping
• Tropical Rain Forest
• Non Native Pests
• Afforestation
• Coral Reef
• Marine Ecosystem

References

• What is biodiversity?
• Global Issues
• Is Man Destroying His Own Food Supply?
• Why diversity matters
• FAO Corporate Document
• Whay is biodiversity
• Biodiversity: Some species could be wiped out 100 times faster than feared, say researchers
• Biodiversity Study Sees More Species in Danger
• Endangered species handbook
• Seven steps to save biodiversity