which are the earth's principal biological systems ? how have they been depleted and how can they be preserved
Answers
The earth has four principal biological systems. These are: fisheries, forests, grasslands and croplands. They form the basis of the world’s economic system. They supply us food and raw materials for industry. These biological systems are being depleted by excessive use. Over fishing is quite common. Forests are being destroyed to obtain firewood for cooking. In many areas of the world, these biological systems have reached an unsustainable level. Grasslands are turning into deserts and produce from croplands is decreasing. It seems they have lost their productivity. The decimation of forests is likely to cause extinction of several species. We must change our outlook and stop overusing the natural resources. We have to hand them over to the coming generations in a healthy state so that they can meet their needs. Consciousness of our moral responsibility as caretakers of the legacy of our children can help to preserve these non-renewable resources.