4.1 BIODIVERSITY - CONCEPTS

Biodiversity

·         Biodiversity itself is a combination of two words, Bio (life) and diversity (variety).

·         It is the number and variety of organisms found within a specified topographical region.

·         It brings up to the varieties of flora, fauna, and micro-organisms, the genes they contain and the ecosystems they form.

·         It relates to the variability among living organisms on the earth, including the variability within and between the species and that within and between the ecosystems.

·         Biodiversity is an arrangement in continuous evolution, from the viewpoint of an individual organism as well as from a viewpoint of species.

·         It is not found uniformly on the earth.
[See Video: https://www.youtube.com/watch?v=aqtdaIkxnQo]
                    https://www.youtube.com/watch?v=iR2AyybowPc

Biodiversity can be discussed at three levels:

·         Genetic diversity

·         Species diversity

·         Ecosystem diversity

Genetic Diversity

·         Genetic biodiversity refers to the variation of genes within species.

·         Genes are the basic building blocks of several life forms.

·         Species are the groups of individual organisms having definite resemblances in their physical characteristics.

·         Human beings inherently belong to the Homo sapiens group.

·         They also differ in their features such as physical appearance, height, etc. This is due to genetic diversity.

·         This genetic diversity is vital for a healthy breeding of population of species.

Species Diversity

·         Species Diversity refers to the variety of species.

·         It relates to the number of species in a demarcated area.

·         The diversity of species can be measured through its abundance, richness, and types.

·         The regions rich in species diversity are called hotspots of diversity.

Ecosystem Diversity

·         The wide differences between types of ecosystem and the diversity of habitats and ecological processes happening inside each ecosystem type set up the ecosystem diversity.

·         The boundaries of communities and ecosystems are not very strictly demarcated.

·         Hence the demarcation of ecosystem boundaries is intricate and difficult.

Importance of Biodiversity

·         The concept of biodiversity is an integral part of many human cultures.

·         Biodiversity plays the following roles:

o    Ecological

o    Economic

o    Scientific

·         It has contributed in several ways to the development of human culture and, in turn, human communities.

·         It has played a major role in shaping the diversity of nature at the genetic, species and ecological levels.

Ecological Role of Biodiversity

·         Each organism contributes something of use to other organisms besides extracting its needs.

·         The major functions done by species which are important for ecosystem function and human survival are:

o    Capture and store energy

o    Produce and decompose organic materials

o    Help to cycle water and nutrients throughout the ecosystem

o    Fix atmospheric gases and help to regulate the climate

·         The more diverse an ecosystem, better are the chances for the species to survive through adversities and attacks, and subsequently, is more productive.

·         Hence, the loss of species would decline the ability of the system to maintain itself.

·         The more the diversity of species in an ecosystem, the more stable the ecosystem is likely to be.

Economic Role of Biodiversity

·         Biodiversity is an important resource in their day-to-day life for all humans.

·         It is comprehended as a reservoir of resources to be drawn upon for the manufacture of food, cosmetic products, and pharmaceuticals.

·         Some of the significant economic commodities that man derives from biodiversity are:

o    Food crops

o    Livestock

o    Forests

o    Fish

o    Medicinal resources

·         The vital part of biodiversity is ‘crop diversity’, which is also known as agro-biodiversity.

·         This idea of biological resources is accountable for the deterioration of biodiversity.

Scientific Role of Biodiversity

·         All species can contribute some evidence to show how life evolved and will continue to evolve.

·         Biodiversity helps in sensing how life functions and the role of each species in sustaining ecosystems.

·         The level of biodiversity is a good indicator of the state of the relationships of human beings with other living species.

Loss of biodiversity

·         About three-fourth of the human population resides in the Tropical regions which occupy only about one-fourth of the total area of the world.

·         The tropical rain forests contain 50 percent of the species on the earth.

·         The excessive population has resulted in the rampant exploitation of resources and deforestation.

·         The destruction of the Tropical regions has resulted in the loss of natural habitats which is catastrophic for the whole biosphere.

·         Natural calamities like forest fires, droughts, floods, volcanic eruptions, earthquakes, etc. cause damage to both flora and fauna of the earth.

·         Pesticides and other pollutants like toxic heavy metals and hydrocarbons destroy the feeble and sensitive species.

·         Loss of biodiversity in an area may cause

o    Decline in plant production

o    Lowered resistance to environmental perturbations

o    Increased variability in definite ecosystem developments such as water use, plant productivity, and disease cycles and pests.

IUCN

·         The IUCN issues data about endangered species universally as the Red List of threatened species.

·         The organization has categorized the threatened species of plants and animals into three categories for the purpose of their conservation.

o    Endangered Species

o    Vulnerable Species

o    Rare Species

Endangered Species

·         It comprises those species which are in danger of extinction.

Vulnerable Species

·         This comprises the species which are probable to be in danger of extinction in near the future if the factors threatening to their extinction continue.

·         Survival of these species is not guaranteed as their population has decreased greatly.

Rare Species

·         The population of these species is very small in the world and they are restricted to limited areas or thinly scattered over a wider area.

Conservation of Biodiversity

·         Biodiversity is important for human existence.

·         All forms of life are so closely interlinked that disturbance in one gives rise to imbalance in the others.

·         As the problem of loss of biodiversity tends to continue, the need of the hour is to educate people to adopt environment-friendly practices and reorient their activities in a way that the development is harmonious with other life forms.

·         The critical problem is not only the conservation of species nor the habitat but the extension of process of conservation.

·         There is an increasing awareness of the fact that such conservation with sustainable use is possible only with the participation and cooperation of local groups and individuals.

Development of institutional structures

·         To create awareness and ensure participation and cooperation, a development of institutional structures at local levels is essential.

Convention on Biodiversity

·         The Government of India signed the Convention on Biodiversity at the Earth Summit.

·         The Earth Summit was held in Rio de Janeiro, Brazil in June 1992.

·         Along with India, 155 other nations have also signed this.

World Conservation Strategy

·         The world conservation strategy has suggested the following steps for biodiversity conservation:

o    Efforts should be made to preserve the species that are endangered.

o    Prevention of extinction needs proper management and planning.

o    Varieties of forage plants, livestock, food crops, timber trees, animals and their wild lineages should be preserved.

·         Every country should recognize habitats of wild flora and fauna, and ensure their protection.

·         Habitats where species breed, feed, rest and nurture their young should be maintained and protected.

·         International trade in animals and wild plants should be regulated.

Wild Life (Protection) Act, 1972

·         To protect, preserve and propagate the diversity of species within natural boundaries, the Government of India passed the Wild Life (Protection) Act, 1972.

·         Under this act only, the sanctuaries and national parks were established and biosphere reserves declared.

Megadiversity

·         There are some countries which are situated in the tropical region; they possess a large number of the species diversity in the World. They are called mega diversity centres.

·         There are 12 such countries, namely Mexico, Columbia, Ecuador, Peru, Brazil, Democratic Republic of Congo, Madagascar, China, India, Malaysia, Indonesia and Australia in which these centres are located.

Hot spots

·         Hotspots are defined according to the vegetation.

·         Plants are vital as they determine the primary productivity of an ecosystem.

·         Most of the hotspots depend on species-rich ecosystems for food, firewood, cropland, and revenue from timber.

[Source: https://byjus.com/]