Importance And Threats To Biodiversity

Importance Of Biodiversity

Ecosystems and their species perform important biological services, for example, green plants remove carbon dioxide and release oxygen into the atmosphere, which helps keep the environment healthy and fit for human life. Economic arguments also provide compelling reasons for conserving species.
Biodiversity has a number of functions  on the Earth. These are as follows:

• Protecting areas from soil erosion, floods and other harmful weather conditions: Vegetation cover helps to protect soils from erosion.  Woodlands and hedges provide useful windbreaks in farm areas, and the vegetation on mudflats and sand dunes can help protect coastal areas from erosion by the sea and wind.

• Reducing the risk of local and global climate change: Ecosystems help maintain a healthy balance of gases in the atmosphere. Trees and other plants store carbon and help prevent the build-up of carbon dioxide in the atmosphere, reducing the risk of global warming.

• Recycling nutrients: Bacteria and fungi play a crucial role in recycling nutrients in ecosystems.  Some plants play a crucial role in the fixation of nitrogen in the soil. Nitrogen fixation is the process of converting atmospheric nitrogen into ammonia.

• Pollination and biological control: Some animals, especially birds, bats and insects perform important functions as pollinators of food plants such as vegetables and fruit, and are also often the natural enemies of weeds, pests and diseases that can harm crops.

• Controlling pollutants: Plants like reeds act as natural filters, helping to remove waste from surface waters and many bacteria can help break down low level pollutants.
• Monitoring the health of the environment: Some species can indicate a change in the environment. For example, the breeding failure among birds of prey can point to a build up of pesticides in the system. Lichens such as those found growing on your university walls and on the trees may be sensitive indicators of levels of air pollution.

• Biodiversity and food:The provision of food is the most fundamental benefit that humans get from other life forms, and humans have always depended on animals and plants for meat, fruit, vegetables, nuts, and other natural products. 80% of human food supply comes from 20 kinds of plants. But humans use 40,000 species for food, clothing and shelter. Biodiversity provides for variety of foods for the planet.

• Medicines: Wild species have been used as sources of drugs for thousands of years. The medicinal potential of plants and animals is often considered a compelling reason to conserve biodiversity as some species are highly valued for their medicinal uses.

• Biodiversity and human health:The shortage of drinking water is expected to create a major global crisis. Biodiversity also plays an important role in drug discovery and medicinal resources. Medicines from nature account for usage by 80% of the world’s population.

• Commercial uses: Human societies have traditionally used plant and animal products like wool and fur for clothing, and wood for building construction and fuel. Other plant and animal products used in industry include feathers, skins, glues, rubber, oils, waxes, starches and dyes.

• Cultural and aesthetic values: Historically, some species have played an important role in the folklore and traditions of many cultures. Species may also have heritage value as national symbols: for example, in Ireland, the three leafed clover (Trifolium sp.) symbolizes the nation’s identity and heritage. Biodiversity also has important recreational and aesthetic values.  Biodiversity also has educational and inspirational value.

Threats To Biodiversity

“Extinction is the most irreversible and tragic of all environmental calamities. With each plant and animal species that disappears, a precious part of creation is callously erased.” – noted American conservation biologist “Michael Soule.”

1. Deforestation and habitat loss: Deforestation is a direct cause of extinction and loss of biodiversity. An estimated 18 million acres of forest are lost each year, due in part to logging and other human practices, destroying the ecosystems on which many species depend. Habitat destruction changes the conditions needed for particular plants and animals to survive. Tropical rainforests in particular, such as the Amazon, hold a high percentage of the world’s known species, yet the regions themselves are in decline due to humans.

2. Over exploitation: Over-hunting, over-fishing and over-harvesting contribute greatly to the loss of biodiversity, killing off numerous species over the past several hundred years. Poaching and other forms of hunting for profit increase the risk of extinction; the extinction of an apex predator — or, a predator at the top of a food chain — can result in catastrophic consequences for ecosystems.

3.  Invasive species: The introduction of non-native species into an ecosystem can threaten endemic wildlife (either as predators or competing for resources), affect human health and upset economies.

4. Pollution: Pollution can have a huge impact, altering the balance within ecosystems, and is the cause of death for millions of animals and plants around the world every year. From the burning of fossil fuels (releasing dangerous chemicals into the atmosphere and, in some cases, depleting ozone levels) to dumping 19 billion pounds of plastic into the ocean every year, pollution completely disrupts the Earth’s ecosystems.

And also acid rain, which is typically caused by the burning of fossil fuels, can acidify smaller bodies of water and soil, negatively affecting the species that live there by changing  breeding and feeding habits.

Reference

This Article is completely based on by the lecture of Dr. Azmol Hasan Bhuiya, Professor, Department of Botany, University of Dhaka

 Some info and pictures have been added by author