Biodiversity

The prefix ‘bio’ literally refers to something related to life and diversity refers to the variety. Biodiversity is the number and variety of organisms found within a specified geographic region. This term popularised by the American socio-biologist Edward Wilson.

It refers to varieties of plants, animals and micro-organisms, genes they contain and the ecosystems they form. It relates to the variability among living organisms on earth, including the variability within and between species and that within and between the ecosystems.

Biodiversity is a system in constant evolution, from view point of species & individual organism. Biodiversity today is the result of 2.5-3.5 billion years of evolution. The average half-life of a species is estimated at between one and four million years, and 99% of the species that have ever lived on earth are today extinct.

Before the advent of humans, earth supported more biodiversity than in any other period. Since then, biodiversity has begun a rapid decline, bearing the brunt of extinction due to overuse. 

The estimates regarding the number of species that we have globally today vary from 2 – 100mn, with 10mn being the best estimate. New species are regularly discovered most of which are yet to be classified (an estimate states that about 40% of fresh water fishes from South America are not classified yet). However today, we are losing species faster than the rate of their discovery annually.

Biodiversity can be discussed at 3 levels: 

1. Genetic Biodiversity: Refers to variation of genes within species. Essential for healthy breeding of population of species.
   • Adaptation leads to speciation.
   • For example, W. Ghats have a greater amphibian species diversity than eastern Ghats
2. Species Diversity: Variety of species. Relates to no. of species in a defined area. Can be measured though richness, abundance & type. 
   • For example, Desert, rain forests, mangroves, coral reefs, wetlands, estuaries, and alpine meadows.
   • Alpha diversity is the species diversity present within each functional community. 
   • Beta diversity is represented by the species diversity between any two patches and their communities. 
   • Gamma diversity of the landscape is the species diversity along the entire range of the mountain slope.
3. Ecosystem Diversity: broad differences between ecosystem types and the diversity of habitats and ecological processes occurring within each ecosystem type constitute the ecosystem diversity. 

The ‘boundaries’ of communities (associations of species) and ecosystems are not very rigidly defined, and so is the boundary of ecosystems as well.

Species diversity X diversity between communities = Biodiversity of larger geographical area

Importance of Biodiversity: 

Biodiversity plays the following roles:

• Ecological: no ecosystem evolves and sustains without any reason – every organism, besides extracting its needs, also contributes something of useful to other organisms.

1. Loss of species would decrease the ability of the system to maintain itself. Just like species with high genetic diversity. Ecosystem with high biodiversity have greater chance of adapting to environmental change.
2. It provides services such as water purification and supply, waste assimilation and the cleaning of air and water, regulation of pests and diseases and soil nutrient cycling and fertility.
3. Biodiversity helps mitigate unpredictable global changes and natural disasters.

• Economic role: It is a resource; One important part ‘crop diversity’ – also called agro-biodiversity. 

1. Biodiversity is seen as a reservoir of resources to be drawn upon for the manufacture of food, pharmaceutical, and cosmetic products. 
2. Important economic commodities from biodiversity:  food crops, livestock, forestry, fish, medicinal resources.
3. Provides Pollinators.
4. This concept of biological resources is responsible for the deterioration of biodiversity.

• Scientific role: Gives insight into how life evolved & will continue to evolve. Helps us understand – how life functions – role of each species in ecosystem.

• Social role:

1. More than 70% of the world’s poor live in rural areas and are directly dependent on the ecosystem/biodiversity goods for their survival.
2. A rich biodiversity is the basis for good health, food security, economic growth, livelihood security and climatic conditions.
3. Many ecosystem or biodiversity goods and services act as a safety net to indigenous peoples, poor and vulnerable groups, women and children. For example, Minor forest produce.

Loss of Biodiversity:  

• Only about one-fourth of the total area of the world, contain about three- fourth of the world human population. Overexploitation of resources and deforestation have become rampant to fulfil the needs of large population. 

• As these tropical rain forests contain 50% of the species on the earth, destruction of natural habitat proved disastrous for the entire biosphere.

• Natural calamities such as earthquakes, floods, volcanic eruptions, forest fires, droughts, etc. cause damage to the flora and fauna of the earth, bringing change the biodiversity of respective affected regions.

• Pesticides and other pollutants such as hydrocarbons and toxic heavy metals destroy the weak and sensitive species.

• Exotic species: natural biotic community can suffer extensive damage. [Invasive species]

• Poaching: animals like tigers, elephants, rhinoceros, crocodiles, minks and birds were hunted mercilessly by poachers for their horn, tusks, hides, etc. It has resulted in the rendering of certain types of organisms as endangered category.

IUCN Red List

International Union of Conservation of Nature and Natural Resources (IUCN) has classified the species of plants and animals into various categories for the purpose of their conservation.

The IUCN Red List or Red Data List (1964) assesses the conservation status of species worldwide. It shows us where and what actions need to be taken to save the building blocks of nature from extinction. It provides a straightforward way to factor biodiversity needs into decision-making processes by providing a wealth of useful information on species.

1. Species that have gone extinct: 
   1. Extinct (EX): last remaining no. of species has died, or is presumed beyond reasonable doubt to have died. For example, dodo.
   2. Extinct in Wild (EW): known only in captivity, in cultivation, or in a naturalized population well outside the past range.
2. Threatened or Threatened with extinction: evaluated on 5 biological factors: 

1. Geographical distribution, 
2. Population size, 
3. Rate of decline, 
4. Degree of population & 
5. Distribution fragmentation.

1. Critically Endangered (CR): Extremely high risk of extinction in immediate future. For example, Java Rhino.
   • Condition: If 90% of the population has been wiped out in the last 10 years, apart from other factors.
2. Endangered (EN): Extremely high risk of extinction in near future. 250. For example, tiger.
   • Condition: If 70% of the population has been wiped out in the last 10 years.  
3. Vulnerable (VU): High risk of extinction in medium term future. 1000. For example, Lion Cheetah.
   • Condition: If 50% of the population has been wiped out in the last 10 years.

1. Lower Risk:

1. Near Threatened (NT): Does not qualify the five criteria at present; but close to fulfilling one of the criteria. Conservation dependent.
2. Least Concerned (LC): No immediate threat.
3. Data Deficient (DD): Inadequate information to kame direct or indirect assessment.

• Other

1. Not evaluated (NE): Species for which data is not available.

Other Major Definitions

Rare Species: Population very small – confined in very small area. Endemic Species: found in some particular areas usually isolated by natural or geographical barriers. For example, Andaman teal, Nicobar pigeon, Andaman wild pic, Mithun in Arunachal Pradesh.

Conservation of Biodiversity: 

Government of India along with 155 other nations have signed the Convention on Biological Diversity at the Earth Summit (UN) held at Rio-de Janeiro, Brazil in June 1992. The world conservation strategy has suggested the following steps for biodiversity conservation:

1. Efforts should be made to preserve the species that are endangered.
2. Prevention of extinction requires proper planning and management.
3. Varieties of food crops, forage plants, timber trees, livestock, animals and their wild relatives should be preserved;
4. Each country should identify habitats of wild relatives and ensure their protection.
5. Habitats where species feed, breed, rest and nurse their young should be safeguarded and protected.
6. International trade in wild plants and animals be regulated.

To protect, preserve & propagate the variety of species within natural boundaries, GoI passed a Wildlife (Protection) Act, 1972, under which National parks & Sanctuaries were established & biosphere reserves declared.

Mega diverse countries

There are some countries which are situated in the tropical region; they possess a large number of the world’s species diversity – Mega diversity centres. 

• Some areas are richer in species than others. Only 2.4% of terrestrial surface holds more than 60% of its diversity.
• These are 36 biologically rich areas around the world that have lost at least 70% of their original habitat.
• There are 17 such countries, namely Mexico, Columbia, Ecuador, Peru, Brazil, Zaire, Madagascar, China, India, Malaysia, Indonesia, Australia, South Africa, Philippines, Papua New Guinea, United States and Venezuela in which these centres are located.

In order to concentrate resources on those areas that are most vulnerable, (IUCN) has identified certain areas as Biodiversity hotspots. Hotspots are defined according to their vegetation. 

• For example, Madagascar has about 85% of the plants and animals are not only found nowhere else in the world, but its people are also among the world’s poorest and rely on slash and burn agriculture for subsistence farming.
• The islands of Hawaii have many unique plants and animals that are threatened by introduced species and land development.

Biodiversity hotspots: 

Biodiversity Hotspots are the regions with very high levels of species richness, high degree of endemism (i.e. species confined to that region & not found anywhere else) and threatened with destruction that conservationists identify for maximum protection.

Initially 25 biodiversity hotspots were identified but subsequently nine more have been added to the list, bringing the total number of biodiversity hotspots in the world to 36. 

Four of these hotspots – cover our country’s exceptionally high biodiversity regions. 

1. W. Ghats, 
2. Sundaland (Indonesian archipelago) and Nicobar island, 
3. Indo-Burma, India and Myanmar
4. Eastern Himalayas have been recently added as the Biodiversity hotspot.

Although all the biodiversity hotspots put together cover less than 2% of the earth’s land area, the number of species they collectively harbour is extremely high and strict protection of these hotspots could reduce the ongoing mass extinctions by almost 30%.

These hotspots are also regions of accelerated habitat loss. 

Patterns of Biodiversity; 

1. Latitudinal gradients: In general, species diversity decreases as we move away from the equator towards the poles. Ecologists and evolutionary biologists have proposed various hypotheses; some important ones are 
2. Speciation is generally a function of time, unlike temperate regions subjected to frequent glaciations in the past, tropical latitudes have remained relatively undisturbed for millions of years and thus, had a long evolutionary time for species diversification;

1. Tropical environments, unlike temperate ones, are less seasonal, relatively more constant and predictable. Such constant environments promote niche specialisation and lead to a greater species diversity.
2. There is more solar energy available in the tropics, which contributes to higher productivity; this in turn might contribute indirectly to greater diversity.

1. Species Area Relationships: German naturalist and geographer Alexander von Humboldt observed that within a region species richness increased with increasing explored area, but only up to a limit. In fact, the relation between species richness and area for a wide variety of taxa (angiosperm plants, birds, bats, freshwater fishes) turns out to be a rectangular hyperbola.

 log S  =  log C  +  Z log A

S = species richness; A = Area;  C = y-intercept

Z = slope of line(regression coeff.) = Value b/w 0.1  to 0.2;

A stable community should not show much variaton in productivity from year to year. 

 Biodiversity in the world: 

• According to IUCN(2004), the total no. of plants & animal species are slightly more than 1.5Mn. But no clear idea about how many are yet to be discovered. Extrapolation estimations: 20mn to 50mn; A more conservative & scientific estimate: 7mn.
  • More than 70%  of all species recorded are animals
    • About 50% of all species are insects.
  • Plants(including algae, fungi, bryophytes, gymnosperms & angiosperms)  are not more than 22%
    • Fungi species are more than fishes, amphibians, reptiles & mammals combined.
  • These estimates do not give any figure for prokaryotes. Conventional taxonomical methods are not suitable for identification of microbial species. And many species are not even culturable under lab conditions.

Biodiversity in India: 

India is one of the 17 mega-diverse countries and is rich in biodiversity &its associated traditional knowledge systems.

There are more than 20,000 species of ants, 3,00,000 species of beetles, 28,000 species of fishes and nearly 20,000 species of orchids.

Biodiversity or Biological Diversity: Immensely rich in wildlife & cultivated species, diverse in form & function but closely integrated in a system through multiple network of interdependencies.

• India has 8% ( 1.6mn) of species in the world. This is twice or thrice then number yet to be discovered.
• Over 81K species of fauna & 47K species of flora (incl. 15K flowering that are endemic(indigenous)) found so far.
• Risk to Bioiversity:
  • Some estimates suggest: 10% of India’s recorded wild flora & 20% of its mammals are on threatened list. Many of these would now be categorised as ‘critical’: verge of extinction, For example, Cheetah, pink-headed duck, mountain quail, forest spotted owlet, & plants like madhuca insignis (Wild Mahua variety) & hubbardia heptaneuron (grass variety).
  • 79 species of mammals, 44 of birds, 15 of reptiles & 3 of amphibians are threatened.
  • 1500 plants endangered. 
  • Flowering plants & vertebrate animals have recently become extinct at a rate estimated to be 50-100 times the average expected natural rate.
• India has 2.4% of world area but 8.1% of species diversity = one of 17 Mega diversity country in the world.
  • 45k species of pant; 90k species of animals have been recorded. 
    • 1.2K species of birds.
  • If only 22% of species are discovered globally; proportionately India has 1L plants & 3L animal species.
  • But many face threat of extinction; We might never be able to record them.
• Due to its large size, range of topography, altitude and climate, India exhibits a rich variety of ecosystems such as forests, grasslands, deserts, wetlands, mangroves and coral reefs.
• These provide basic needs such as food, fibre, medicine, fodder, fuel wood and timber.
• India’s tribal population is also dependent on forests and natural resources to a significant extent.

 The Threats: India’s developmental activities are greatly affecting biodiversity and natural resources such as water, forests, fisheries and marine resources.

• India possesses around 18% of the world’s population, but only 2.4% of land and 4.2% of water resources.
• Rapid development that pertains to industry and infrastructure is required to achieve a high GDP growth rate. Emissions from industry and the transport sectors are at a high level.
• There is also indiscriminate discharge of solid wastes, industrial effluents and domestic sewage with considerable impact.

How to tackle the threats?

• The resources are being over-exploited which in turn is affecting their renewability.
• Proactive efforts are needed in ecosystem management that involves both the government and community.Biodiversity conservation has traditionally been the responsibility of the environment sector.
• Some measures have been helpful such as the: 
  • enforcement of legal decisions, 
  • ‘polluters pay principles’ and 
  • the incorporation of protected areas.
• As the developmental sector generally ignores its responsibility towards biodiversity conservation, a more responsible approach towards biodiversity management is needed.

What is meant by mainstreaming?

• Mainstreaming or inclusion means integrating/including actions related to conservation.
• This can be done by promoting the sustainable use of biodiversity in strategies relating to production sectors such as agriculture, fisheries, forestry, tourism, and mining.
• It also refers to including biodiversity considerations in poverty reduction and national sustainable development plans.

Benefits of Mainstreaming:

• Mainstreaming will help to reduce the negative impacts on biodiversity.
• For example, in agriculture, minimising the use of and optimising the application of chemical fertilizers and pesticides can reduce negative impacts on soil, groundwater, surrounding habitats and wildlife.
• Small-scale farming or aquaculture activities undertaken in a sustainable manner might prove beneficial to wild species.
• Positive biodiversity impacts might also be optimised through promoting people’s access to benefits derived from the use of biological resources.
• Community-based joint forest management, promotion of traditional multi-species and multi-variety agricultural practices, securing access to medicinal resources for local use, strengthening traditional and cultural practices and governing the use of wild resources are examples.
• Further, the fair and equitable sharing of the benefits arising out of the use of biological resources and the knowledge associated by users (industries) to the providers (communities) will act as incentives to local communities in the conservation and sustainable use of bio-resources.

(This is one of the objectives of CBD, and the Biological Diversity Act of India)

 Conclusion:

• Achieving many national and international biodiversity goals such as the National Biodiversity Strategies and Action Plans and the Aichi Biodiversity Targets, as well as meet CBD objectives, biodiversity integration into developmental sectors is a prerequisite.
• After understanding its (industry) relationship with biodiversity, each sector should come up with appropriate mechanisms for conservation and sustainable biodiversity use.
• Further, research institutions should be roped in to provide appropriate management strategies, with budget options.
• Public and private entrepreneurs, entities and the communities should come forward to conserve biodiversity.

What is biodiversity, and why is it significant in UPSC preparation?

Biodiversity refers to the variety of life forms, including plants, animals, microorganisms, and ecosystems. It’s significant for UPSC aspirants as it covers environmental conservation, sustainable development, and India’s ecological challenges.

How is biodiversity classified, and why is this classification important for UPSC?

Biodiversity is classified into genetic, species, and ecosystem diversity. Understanding this classification helps aspirants analyze environmental issues, conservation policies, and biodiversity management strategies, integral to UPSC exams.

What are biodiversity hotspots, and which ones are important from India’s perspective in UPSC exams?

Biodiversity hotspots are regions with exceptionally high levels of biodiversity facing threats of habitat loss. India’s biodiversity hotspots include the Western Ghats, Eastern Himalayas, Indo-Burma, and Sundaland, making them essential for UPSC preparation.

Why is biodiversity conservation crucial for India’s ecological balance and sustainable development, as asked in UPSC?

Biodiversity conservation ensures ecosystem stability, supports livelihoods, maintains water cycles, and mitigates climate change impacts. UPSC aspirants need this understanding to address environmental and policy-related questions effectively.

What are the key threats to biodiversity in India frequently discussed in UPSC exams?

Major threats to biodiversity in India include habitat destruction, pollution, invasive species, climate change, and unsustainable resource use. Addressing these threats is central to India’s environmental policies and frequently features in UPSC questions.