Sustaining the planet is one of the most significant challenges to us. Tremendous increase in population, loss of biodiversity, climate change are defining issues that we are facing today.
By 1800, the population reached 1 billion, and increased up to 7 billion in October 2011. The population explosion causes lack of resources such as land, food, water, minerals and increase in waste products which lead to pollution.
Humans have destroyed the habitats of animals and plants by clearing land for agriculture, industrialization and urbanization to cope with increasing population. In addition, human activities such as pollutants, introducing invasive species, wars lead to decline in animal and plant species, and some of them are currently under threat.
Ex. Introducing goats by sailors on Pinta Island threaten the giant tortoises by interspecific competition, as the goats are relatively fast breeding mammals compared to others.
Human population is now reaching 8 billion, and there is a carrying capacity in our planet as space, life-sustaining resources are limited.
