About Biodiversity
Value of Biodiversity and Ecosystem Services
Biological diversity - or biodiversity - is the term given to the variety of life on Earth and the natural patterns it forms. The biodiversity we see today is the fruit of billions of years of evolution, shaped by natural processes and, increasingly, by the influence of humans. It forms the web of life of which we are an integral part and upon which we so fully depend.
This diversity is often understood in terms of the wide variety of plants, animals and microorganisms. So far, about 1.75 million species have been identified, mostly small creatures such as insects. Scientists reckon that there are actually about 13 million species, though estimates range from three to 100 million.
Biodiversity also includes genetic differences within each species - for example, between varieties of crops and breeds of livestock. Chromosomes, genes, and DNA-the building blocks of life-determine the uniqueness of each individual and each species.
Yet another aspect of biodiversity is the variety of ecosystems such as those that occur in deserts, forests, wetlands, mountains, lakes, rivers, and agricultural landscapes. In each ecosystem, living creatures, including humans, form a community, interacting with one another and with the air, water, and soil around them.
The Value of Biodiversity
- A network of marine protected areas, with the aim of conserving 20%-30% of the seas and oceans, could cost between $5bn and $19bn, but help to safeguard $70bn to $80bn worth of fish catches, and the provision of marine ecosystem services valued at $4.5 to $6.7 trillion annually.
- The annual economic median value of fisheries supported by mangrove habitats in the Gulf of California has been estimated at $37,500 per hectare of mangrove fringe. The value of mangroves as coastal protection may be as much as $300,000 per kilometre of coastline.
- Nature-based tourism in Africa generates approximately the same amount of revenue as farming, forestry and fisheries combined.
- The national parks of Canada store 4.43 gigatonnes (billion metric tonnes) of carbon, a service worth between $11bn and $2.2 trillion depending on the price of carbon in the market. The protected areas of Mexico store 2.45 gigatonnes of carbon dioxide equivalent – more than five years of Mexico’s carbon dioxide emissions in 2004, and valued at $12.2 billion.
- A report in 2003 estimated the total value of annual benefits of the United Kingdom’s forests to its people to be around £1 billion. They included recreation (£393 m), biodiversity (£386 m), landscape (£150 m) and carbon sequestration (£94 m). The estimate, carried out by Britain’s Forestry Commission, did not include values such as the contribution of forests to the supply and quality of fresh water, the cleansing of pollutants from the air, and reduction of soil erosion.
- The Great Barrier Reef is estimated to contribute nearly 6 billion Australian Dollars to the country’s economy, counting only the value of tourism, other recreational activities and commercial fishing.
It is the combination of life forms and their interactions with each other and with the rest of the environment that has made Earth a uniquely habitable place for humans. Biodiversity provides a large number of goods and services that sustain our lives.
Protecting biodiversity is in our self-interest. Biological resources are the pillars upon which we build civilizations. Nature's products support such diverse industries as agriculture, cosmetics, pharmaceuticals, pulp and paper, horticulture, construction and waste treatment. The loss of biodiversity threatens our food supplies, opportunities for recreation and tourism, and sources of wood, medicines and energy. It also interferes with essential ecological functions.
Our need for pieces of nature we once ignored is often important and unpredictable. Time after time we have rushed back to nature's cupboard for cures to illnesses or for infusions of tough genes from wild plants to save our crops from pest outbreaks. What's more, the vast array of interactions among the various components of biodiversity makes the planet habitable for all species, including humans. Our personal health, and the health of our economy and human society, depends on the continuous supply of various ecological services that would be extremely costly or impossible to replace. These natural services are so varied as to be almost infinite. For example, it would be impractical to replace, to any large extent, services such as pest control performed by various creatures feeding on one another, or pollination performed by insects and birds going about their everyday business.
"Goods and Services" provided by ecosystems include:
- Provision of food, fuel and fibre
- Provision of shelter and building materials
- Purification of air and water
- Detoxification and decomposition of wastes
- Stabilization and moderation of the Earth's climate
- Moderation of floods, droughts, temperature extremes and the forces of wind
- Generation and renewal of soil fertility, including nutrient cycling
- Pollination of plants, including many crops
- Control of pests and diseases
- Maintenance of genetic resources as key inputs to crop varieties and livestock breeds, medicines, and other products
- Cultural and aesthetic benefits
- Ability to adapt to change
Why we are losing biodiversity
The threats to Biodiversity
- Habitat loss through changes of land use in particular the conversion of natural ecosystems to cropland, continues to be the biggest direct cause of biodiversity loss. Already, more than half of the Earth’s 14 terrestrial biomes have had between 20% and 50% of their total area converted to cropland.
- Unsustainable use of ecosystems and over-exploitation of biodiversity continue to be major threats. Many species are used by humans to fulfill basic needs. Many species are in a state of decline because they are being used at unsustainable levels or are being harvested in such a way that threatens the ecosystems on which they depend. These declines are widespread.
- Climate change is projected to become a progressively more significant threat to biodiversity in the coming decades. Already, changes to the timing of flowering and migration patterns as well as to the distribution of species have been observed worldwide . In Europe, over the last forty years, the beginning of the growing season has advanced by 10 days on average . These types of changes can alter food chains and create mismatches within ecosystems where different species have evolved synchronized inter-dependence, for example between nesting and food availability.
- Plants, animals and micro-organisms transported deliberately or accidentally to an area outside their natural geographical ranges can cause great damage to native species by competing with them for food, eating them, spreading diseases, causing genetic changes through inter-breeding with native species or populations, and disrupting various aspects of the food web and the physical environment. More than 530 alien species with a demonstrated impact on biodiversity have been found across 57 countries for which data were collated, with an average of over 50 such species per country (and a range from nine to over 200)
- The accumulation of pollution such as phosphorus and nitrogen, largely from excess fertilizers running off farmland, and from sewage and other effluents, causes the build-up of algae able to benefit from the added nutrients. The algae themselves can be toxic and therefore create a health hazard, but the greatest damage to biodiversity is caused when they decompose and use up large quantities of oxygen in the water, creating “dead zones” where other forms of life cannot survive. The number of such dead zones increased from 149 in 2003 to over 200 in 2006. The continuing release pollutants from urban and agricultural sources combined with projected growth in coastal development and agricultural intensification may lead to a multiplication of the number of dead zones in the coming decades, unless substantial changes in policy are implemented.
When most people think of the dangers besetting the natural world, they think of the threat to other creatures. Declines in the numbers of such charismatic animals as pandas, tigers, elephants, whales, and various species of birds, have drawn world attention to the problem of species at risk. Species have been disappearing at up to 1000 times the natural rate, and this is predicted to rise dramatically. Based on current trends, an estimated 34,000 plant and 5,200 animal species - including one in eight of the world's bird species - face extinction. For thousands of years we have been developing a vast array of domesticated plants and animals important for food. But this treasure house is shrinking as modern commercial agriculture focuses on relatively few crop varieties. And, about 30% of breeds of the main farm animal species are currently at high risk of extinction.
While the loss of individual species catches our attention, it is the fragmentation, degradation, and outright loss of forests, wetlands, coral reefs, and other ecosystems that poses the gravest threat to biological diversity. Forests are home to much of the known terrestrial biodiversity, but about 45 per cent of the Earth's original forests are gone, cleared mostly during the past century. Despite some regrowth, the world's total forests are still shrinking rapidly, particularly in the tropics. Up to 10 per cent of coral reefs - among the richest ecosystems - have been destroyed, and one third of the remainder face collapse over the next 10 to 20 years. Coastal mangroves, a vital nursery habitat for countless species, are also vulnerable, with half already gone.
Global atmospheric changes, such as ozone depletion and climate change, only add to the stress. A thinner ozone layer lets more ultraviolet-B radiation reach the Earth's surface where it damages living tissue. Global warming is already changing habitats and the distribution of species. Scientists warn that even a one-degree increase in the average global temperature, if it comes rapidly, will push many species over the brink. Our food production systems could also be seriously disrupted.
The loss of biodiversity often reduces the productivity of ecosystems, thereby shrinking nature's basket of goods and services, from which we constantly draw. It destabilizes ecosystems, and weakens their ability to deal with natural disasters such as floods, droughts, and hurricanes, and with human-caused stresses, such as pollution and climate change. Already, we are spending huge sums in response to flood and storm damage exacerbated by deforestation; such damage is expected to increase due to global warming.
The reduction in biodiversity also hurts us in other ways. Our cultural identity is deeply rooted in our biological environment. Plants and animals are symbols of our world, preserved in flags, sculptures, and other images that define us and our societies. We draw inspiration just from looking at nature's beauty and power.
While loss of species has always occurred as a natural phenomenon, the pace of extinction has accelerated dramatically as a result of human activity. Ecosystems are being fragmented or eliminated, and innumerable species are in decline or already extinct. We are creating the greatest extinction crisis since the natural disaster that wiped out the dinosaurs 65 million years ago. These extinctions are irreversible and, given our dependence on food crops, medicines and other biological resources, pose a threat to our own well-being. It is reckless if not downright dangerous to keep chipping away at our life support system. It is unethical to drive other forms of life to extinction, and thereby deprive present and future generations of options for their survival and development.
Can we save the world's ecosystems, and with them the species we value and the other millions of species, some of which may produce the foods and medicines of tomorrow? The answer will lie in our ability to bring our demands into line with nature's ability to produce what we need and to safely absorb what we throw away.
Action for Biodiversity
A new philosophy
In 1992, the largest-ever meeting of world leaders took place at the United Nations Conference on Environment and Development in Rio de Janeiro, Brazil. An historic set of agreements was signed at the "Earth Summit," including two binding agreements, the Convention on Climate Change, which targets industrial and other emissions of greenhouse gases such as carbon dioxide, and the Convention on Biological Diversity, the first global agreement on the conservation and sustainable use of biological diversity. The biodiversity treaty gained rapid and widespread acceptance. Over 150 governments signed the document at the Rio conference, and since then more than 187 countries have ratified the agreement.
The Convention has three main goals:
- The conservation of biodiversity
- Sustainable use of the components of biodiversity
- Sharing the benefits arising from the commercial and other utilization of genetic resources in a fair and equitable way
The Convention is comprehensive in its goals, and deals with an issue so vital to humanity's future, that it stands as a landmark in international law. It recognizes-for the first time-that the conservation of biological diversity is "a common concern of humankind" and is an integral part of the development process. The agreement covers all ecosystems, species, and genetic resources. It links traditional conservation efforts to the economic goal of using biological resources sustainably. It sets principles for the fair and equitable sharing of the benefits arising from the use of genetic resources, notably those destined for commercial use. It also covers the rapidly expanding field of biotechnology, addressing technology development and transfer, benefit-sharing and biosafety. Importantly, the Convention is legally binding; countries that join it are obliged to implement its provisions.
The Convention offers decision-makers guidance based on the precautionary principle that where there is a threat of significant reduction or loss of biological diversity, lack of full scientific certainty should not be used as a reason for postponing measures to avoid or minimize such a threat. The Convention acknowledges that substantial investments are required to conserve biological diversity. It argues, however, that conservation will bring us significant environmental, economic and social benefits in return.
Private companies, landowners, fishermen, and farmers take most of the actions that affect biodiversity. Governments need to provide the critical role of leadership, particularly by setting rules that guide the use of natural resources, and by protecting biodiversity where they have direct control over the land and water. Under the Convention, governments undertake to conserve and sustainably use biodiversity. They are required to develop national biodiversity strategies and action plans, and to integrate these into broader national plans for environment and development. This is particularly important for such sectors as forestry, agriculture, fisheries, energy, transportation and urban planning. Other treaty commitments include:
- Identifying and monitoring the important components of biological diversity that need to be conserved and used sustainably
- Establishing protected areas to conserve biological diversity while promoting environmentally sound development around these areas
- Rehabilitating and restoring degraded ecosystems and promoting the recovery of threatened species in collaboration with local residents
- Respecting, preserving and maintaining traditional knowledge of the sustainable use of biological diversity with the involvement of indigenous peoples and local communities
- Preventing the introduction of, controlling, and eradicating alien species that could threaten ecosystems, habitats or species
- Controlling the risks posed by organisms modified by biotechnology
- Promoting public participation, particularly when it comes to assessing the environmental impacts of development projects that threaten biological diversity
- Educating people and raising awareness about the importance of biological diversity and the need to conserve it
- Reporting on how each country is meeting its biodiversity goals.
While governments should play a leadership role, other sectors of society need to be actively involved. After all, it is the choices and actions of billions of individuals that will determine whether or not biodiversity is conserved and used sustainably.
In an era when economics is a dominant force in world affairs, it is more important than ever to have business willingly involved in environmental protection and the sustainable use of nature. Some companies have revenues far greater than those of entire countries, and their influence is immense. Fortunately, a growing number of companies have decided to apply the principles of sustainable development to their operations. For example, a number of forestry companies-often under intense pressure from environmental boycotts-have moved from clear-cutting to less destructive forms of timber harvesting. More and more companies have also found ways to make a profit while reducing their environmental impacts. They view sustainable development as ensuring long-term profitability and increased goodwill from their business partners, employees, and consumers. Local communities play a key role since they are the true "managers" of the ecosystems in which they live and, thus, have a major impact on them. Many projects have been successfully developed in recent years involving the participation of local communities in the sustainable management of biodiversity, often with the valuable assistance of NGOs and intergovernmental organizations.
Finally, the ultimate decision-maker for biodiversity is the individual citizen. The small choices that individuals make add up to a large impact because it is personal consumption that drives development, which in turn uses and pollutes nature. By carefully choosing the products they buy and the government policies that they support, the general public can begin to steer the world towards sustainable development. Governments, companies, and others have a responsibility to lead and inform the public, but finally it is individual choices, made billions of times a day, that count the most.
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