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Finding 1. Human actions are fundamentally, and to a significant extent irreversibly, changing the diversity of life on Earth, and most of these changes represent a loss of biodiversity. Changes in important components of biological diversity were more rapid in the past 50 years than at any time in human history. Projections and scenarios indicate that these rates will continue, or accelerate, in the future.
Species extinction is a natural part of Earth's history. However, over the past 100 years, humans have increased the extinction rate by at least 100 times compared to the natural rate, leading to a net loss of biodiversity. Some 12% of bird species, 23% of mammals, 25% of conifers, and 32% of amphibians are currently threatened with extinction, and similarly alarming threats of extinction may apply to aquatic organisms.
Many animal and plant populations have declined in numbers, geographical spread, or both. Genetic diversity has also declined globally, particularly among domesticated plants and animals in agricultural systems.
The distribution of species on Earth is becoming more homogeneous. This is caused by the extinction of species or loss of populations that had been unique to particular regions, and by the invasion or introduction of species into new areas.
Virtually all of Earth's ecosystems have now been dramatically transformed through human actions. Due to the expansion of agriculture, cities and infrastructure, the conversion of ecosystems is expected to continue between now and 2050. More...
Finding 2. Biodiversity contributes both directly and indirectly to many constituents of human well-being, including security, basic material for a good life, health, good social relations, and freedom of choice and action.
Over the last century, many people have benefited from the transformation of natural ecosystems and the exploitation of biodiversity, but the losses in biodiversity and changes in ecosystem services have adversely affected the well-being of some people and exacerbated poverty in some social groups.
Many of the actions that have caused the homogenization or loss of biodiversity have provided substantial benefits to humans. Agriculture, fisheries, and forestry, for example, have yielded revenues that have enabled investments in industrialization and economic growth. However, the benefits have not been fairly distributed among people and many of the costs of changes in biodiversity have not been taken into account by decision-makers.
When humans modify an ecosystem to improve one of the services it provides, it generally results in changes to other ecosystem services. For example, actions to increase food production can lead to reduced water availability for other uses, and degraded water quality. Although a few ecosystem services have been enhanced by humans, many other ecosystem services have been degraded.
Many costs associated with changes in biodiversity may be slow to become apparent, or may appear only at some distance from where biodiversity was changed. Some changes in ecosystems are gradual until a particular pressure on the ecosystem reaches a threshold, at which point rapid shifts to a new state occur. For instance, a steady increase in fishing pressure can cause the sudden collapse of fisheries.
Biodiversity loss is important in its own right because biodiversity has spiritual, aesthetic, recreational, and other cultural values, because many people ascribe intrinsic value to biodiversity, and because it represents unexplored options for the future. More...
Finding 3. Although many individuals benefit from the actions and activities that lead to biodiversity loss and ecosystem change, the full costs borne by society is often higher. This is revealed by improved valuation techniques and information on ecosystem services.
Even in cases where our knowledge of benefits and costs is incomplete, a precautionary approach may be justified when the costs associated with ecosystem changes may be high or the changes irreversible.
Even in cases where the costs borne by society exceeded the benefits, ecosystem conversion has often been promoted because the cost associated with the loss of ecosystem services was not taken into account, because the private gains were significant (although less than the public losses), and also because subsidies sometimes distorted the market.
The benefits that could be gained from better ecosystem management are poorly reflected in conventional economic indicators. A country could cut its forests and deplete its fisheries and this would show only as a positive gain in GDP despite the loss of the capital asset.
The costs resulting from ecosystem "surprises", such as extreme events like floods and fire, can be very high.
The costs and risks associated with biodiversity loss are expected to increase, and to affect disproportionately the poor who depend more heavily on local ecosystem service.
New tools exist to better quantify the different values people place on biodiversity and ecosystem services. However, the value of some ecosystem services is difficult to quantify, and often not taken into account in decision making. More...
Finding 4. Direct and indirect drivers will continue to cause biodiversity loss and changes in ecosystem services, either steadily or even increasingly.
The main indirect drivers are changes in human population, economic activity, and technology, as well as socio-political and cultural factors.
The main factors directly driving biodiversity loss are: habitat change, such as fragmentation of forests; invasive alien species that establish and spread outside their normal distribution; overexploitation of natural resources; excessive fertilizer use leading to excessive levels of nutrients in soil and water and other forms of pollution; and climate change More...
Finding 5. Many of the actions that have been taken to conserve biodiversity and promote its sustainable use have been successful in limiting biodiversity loss. Rates of loss are now lower than they would have been in the absence of such actions. Less biodiversity would exist today had not communities, NGOs, governments, and, to a growing extent, business and industry taken actions to conserve biodiversity, mitigate its loss, and support its sustainable use. To achieve greater progress toward biodiversity conservation, it will be necessary (but not sufficient) to strengthen a series of actions that focus primarily on conservation and sustainable use of biodiversity and ecosystem services.
Actions that focus primarily on conservation include: protected areas; species protection and recovery measures for threatened species; conservation of genetic diversity; both on and off sites (such as in gene banks); and ecosystem restoration.
Actions that focus primarily on sustainable use include: providing economic incentives; incorporating biodiversity considerations into management practices (for instance in agriculture, forestry, and fisheries); ensuring that local communities benefit from biodiversity.
Actions that address both conservation and sustainable use include: increasing coordination between international agreements that affect biodiversity and resource use; increasing public awareness, communication, and education; improving our capacity to assess the consequences of ecosystem change for human well-being; and increasing the integration between different policy areas.
However, many of all the above actions will not be sufficient unless other indirect and direct drivers of change are addressed and certain enabling conditions are met. More...
Finding 6. Unprecedented additional efforts would be needed to achieve, by 2010, a significant reduction in the rate of biodiversity loss at all levels.
Indeed, the challenge is great, as it can take many years for human institutions to act and for positive and negative impacts of human actions on biodiversity and ecosystem to become apparent.
Given appropriate actions, it is possible to achieve, by 2010, a reduction in the rate of biodiversity loss for certain aspects of biodiversity and in certain regions. The rate of habitat loss, for instance, is now slowing in some regions, though this may not necessarily translate into lower overall rates of species loss.
Decision-making at all levels could be improved through a better understanding of the impacts of drivers on biodiversity, ecosystem functioning, and ecosystem services. Since changes take place over different time frames, longer-term goals and targets - say, for 2050 - are needed in addition to short-term targets to guide policy and actions.
While biodiversity makes important contributions to human well-being, many of the actions needed to promote economic development and reduce hunger and poverty are likely to reduce biodiversity. Thus, the 2015 targets of the Millennium Development Goals of poverty alleviation and the 2010 target of reducing the rate of biodiversity loss need to be addressed jointly.
People and decision-makers today still have the power to choose among a very wide array of possible approaches, and these choices will have different implications for biodiversity and human well-being of current and future generations.
Depending on the path that will be taken, the world in 2100 could still have a substantial biodiversity or be relatively homogenized with relatively low levels of diversity. More...
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