How are the earth’s principal biological systems being depleted?

The earth’s principal biological systems are four. They are fisheries, forests, grasslands and croplands. They are the foundation of the global economy. Their productivity has become impaired due to human pressure on them. Forests have been cleared. Grasslands have been converted into barren wasteland. Forests are cut down for fuel. Fisheries are exploited on a large scale for protein. The world’s increasing population is the cause behind the depletion of these biological systems.

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The four principal biological systems of the earth are croplands, fisheries, forests and grasslands. Their productivity has become impaired because of human pressure on them. Forests have been cleared. Grasslands have been converted into wastelands. People are overfishing for protein. The world’s increasing population is the cause behind the depletion of these biological systems.