Explain the three causes for biodiversity depletion.
- Biodiversity means a different type of species whether plants or animals that reside in a particular area which gives the area its diversity. But in recent times, a great deal of biodiversity is being depleted due to many and mostly human activity. The following are the 3 main causes for depletion of biodiversity:-
- Habitat loss: Human activity like deforestation for the purpose of agriculture, urbanization, the establishment of industries etc are the causes that have led to a decrease in the forest cover of the earth surface. Animals that are adapted to live there lose their habitat due to which they neither have a home to reside nor they have time to become adapted to the new surrounding that is being built. Besides due to these human activities fragmentation of the forest takes places which disrupts the migration routes or many animals and also divides the group of animals into different parts compared to when the forest was continuously and the animals lived as a whole ecosystem along with forest. These activities have led to the disappearance of many species in many parts of the earth.
- Overexploitation: Natural resources have been used by us for a very long time. But as the human population increases the requirement also increases but the source that is providing us with the materials that we require is finite or doesn't get enough time to replenish before we start using it again. Sometimes we exploit them too much where they are forced to work more than their capacity to provide us with it. For example, if we use an agriculture land to produced certain crop but don't give it a break between 2 crops to replenish its nutrient table then after some time the land becomes barren and then chemical fertilizers are used which are not good for our health either. Or when a certain pond or river is used for obtaining fishes and when it is overfished the fish population starts declining and after some time there will be no fish left in the pond to fish.
- Alien/ invasive species: For our own benefit or enjoyment we have introduced certain species in areas where they don't belong. These species are called invasive species. They don't belong to that ecosystem, so when they are introduced there they start competing with the native species already present there and in some cases, they even overrule the native species due to which the native species either all extinct or migrate to the different place. For example, Water hyacinth or water lily that is invasive for the native water plant present in the pond or river, African catfish ( Clarias gariepinus) which is a threat to the native catfish already present here.