An ecosystem can be defined as a community of living and nonliving things. Examples of ecosystems include rain forests, prairies, desert, ocean, coral reefs and forests. Ecosystems are very interconnected; if the habitat of a particular specie is under threat, the whole ecosystem can be damaged. The are many problems with the ecosystems of the Earth, most of them caused by human activity.
The environmental cycles, or continuous circulation of water, carbon and other nutrients, are vitally important for ecosystems. Ecosystems suffer from water withdrawals from rivers and lakes for urban uses, irrigation and industrial applications. According to the website Green Facts, the concentration of carbon dioxide in the atmosphere has increased by one third since 1750, the time industrialization began.
Green Facts reports that animal and plant populations have declined over the past 50 years in both numbers and spread. The website asserts that human activity has caused between 50 and 1,000 times more extinctions pf plant and animal species in the last 100 years than would have happened due to natural processes. For example, a quarter of mammal species are threatened by extinction.
Biodiversity refers to the number of different species living in an ecosystem. A decline in biodiversity is a problem common to many ecosystems. As unique species found in only certain parts of the world become extinct, they are replaced by more generic species. For example, some species native to the Baltic Sea can be found in places such as the North American Great Lakes.
Problems with ecosystems have a sizable effect on people. Ecosystem services, including food production, timber and fisheries, are important for economic activity and employment. While exploitation of ecosystems can result in short-term economic gains, people are left with fewer resources to exploit in the future. Accordingly, it is necessary to ensure a sustainable use of the world's forests, oceans and other ecosystems. In addition, ruined ecosystems result in pollution that has a negative impact on people's health.
