WHAT IS A HABITAT?
It is important to remember that the living and non-living parts of an ecosystem are dependent upon one another. "Nothing can live alone." Each living organism requires a certain set of physical and chemical conditions. Climate and soil conditions determine the kinds of animals that live there.
If the correct sets of physical and chemical conditions exist, organisms thrive. Large herds of grazing animals exist only where grasses are abundant. If trees invade the area, animals that prefer trees become more common. Where trees produce too much shade, the growth of grass is limited, and the number of grazing animals declines.
Although large animals are more obvious, an ecosystem includes many different kinds of organisms. Each organism has its own special "home" within the ecosystem. The place in an ecosystem where an organism prefers to live is its habitat. But, a habitat is more than just a place to live. It must meet all of the needs of the organism. A good habitat provides enough food and water, suitable living space, and cover. Cover describes those places where animals hide to escape predators or where the young are protected from harm. Cover also provides the animals with shelter from harsh weather.
If the cover, food, water, or living space disappears, the wildlife will also disappear. The disappearance of these necessities may be due to natural changes in an ecosystem, or...
it may be due to human activities.
HOW ARE WE DESTROYING THE WORLD'S HABITATS?
The total human demand on the planet's natural resources exceeds the Earth's capacity by 25%.
Mining, the burning of fossil fuels and polluting industrial activities, intensive agriculture involving excessive chemicals, deforestation for timber and agriculture, the creation of road networks that fragment ecosystems, the paving of the Earth's surface, and the over extraction of water from aquifiers - all these activities are changing the environment irrevocably. The delicate balance between the species that make up the Earth's rich and varied ecosystems has been disrupted, and thousands of life forms are being pushed towards extinction by the activities of a single species.
By destroying ecosystems, we are sowing the seeds of our own destruction, because it is on these very ecosystems that we depend for our survival. Forests absorb carbon dioxide and stop soil from being washed away, mangroves filter impurities and protect the coastline, oceans help regulate the climate.
Signs of a warming climate are apparent across the world, and the change is occurring so rapidly that many species will have no time to adapt. Rising temperatures are leading to less predictable weather patterns, and more extreme weather events. This is interfering with plant growth and natural animal breeding, often upsetting mutually dependent relationships and putting many species, not least humans, under increased strain. The way of life - the very survival - of millions of people and hundreds of thousands of species, is threatened.
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