Biodiversity refers to the variability among living organisms, encompassing the number of species found in a region—particularly its flora (plants) and fauna (animals).
In broader terms, it encompasses all life on Earth, including plants, animals, and microorganisms, as well as the genetic material they contain. It also covers the relative abundance and genetic variation among organisms inhabiting terrestrial, marine, and aquatic ecosystems.
The term ‘biological diversity’ or ‘biodiversity’ was initially coined by Raymond F. Dasmann in 1968 in his book titled “A Different Kind of Country”. According to Heywood (1995), biodiversity is “the total variability of life on the Earth.”
Thus, biodiversity signifies the variety and variability of life forms within the natural world, often categorized by the number and diversity of living organisms.
Biodiversity is essential for sustaining human life by providing fundamental resources such as food, fuel, and shelter.
It contributes to the formation and enrichment of soil through organic matter, and enhances air quality by enabling plants to absorb carbon dioxide (CO₂) and release oxygen (O₂), thereby regulating atmospheric composition.
Forests play a vital role in soil erosion prevention and climate stabilization by acting as carbon sinks.
Moreover, biodiversity mitigates the impact of natural disasters, and its degradation can intensify problems related to these essential ecosystem services.
Hence, the loss of biodiversity threatens food security, environmental balance, and human welfare.
Biodiversity loss is defined as the extinction of species, from single-celled organisms to top predators, within a given area.
Such loss equates to the death of ecosystems and is irreversible. Once species are lost beyond natural regeneration rates, extinction is said to be occurring.
This loss is mainly driven by human-induced activities such as deforestation, urban sprawl, and land conversion for agriculture, often leading to ecosystem collapse.
In earlier centuries, hunting was the primary threat, but today, key causes include:
Coastal urbanization, for instance, has resulted in the destruction of wetlands and mangrove forests.
Extinction rates today are more than 100 times higher than historical averages, especially in the last 300 years.
Species richness may sometimes increase due to community-led conservation, but overall decline leads to negative ecological and societal consequences.
It is critical to consider both the variety and abundance of species to fully assess biodiversity loss.
This includes the degradation of both flora and fauna in terms of their quality and quantity.
Biodiversity refers to the variety of life forms on Earth, and its reduction is a serious environmental concern. In recent decades, human-induced factors have contributed far more to biodiversity loss than natural causes. The key contributors to this ongoing loss are described below:
Habitats are vital for the survival of plants and animals. When these areas are destroyed or altered due to human expansion or economic exploitation, many species are displaced or driven to extinction.
Deforestation, conversion of land for agriculture, industrial use, and urban development are major causes of habitat destruction. As natural spaces shrink and split into disconnected patches, species populations are isolated, making survival more difficult.
Fragmented habitats also restrict the ability of species to migrate, reproduce, or adapt to environmental changes. It is estimated that nearly 67% of all threatened species are impacted by habitat degradation and fragmentation.
Pollution resulting from unregulated industrialization and intensive agriculture significantly harms ecosystems. The excessive use of pesticides, fertilizers, and incidents such as marine oil spills disrupt aquatic and terrestrial life.
Persistent pollutants from urban runoff and farming operations contribute to the growth of 'dead zones'—areas in water bodies where most life cannot survive.
The accumulation of non-biodegradable waste, including plastics, in the oceans has severely affected marine mammals, birds, and fish populations. Toxic discharge and vehicular emissions further contribute to this biodiversity crisis.
Human greed and unsustainable practices have led to the rampant exploitation of plant and animal resources. This includes both legal overharvesting and illegal trade of endangered species.
Overfishing has depleted some fish populations by more than 90%, with large parts of the ocean now considered overfished and facing collapse.
Commercial hunting and global black markets in exotic wildlife have made animals like elephants, rhinos, tigers, and valuable timber species targets of exploitation. This billion-dollar illegal trade poses a major risk to biodiversity worldwide.
Modern climate change, accelerated by human activity, is occurring at a rate too fast for many species to adapt. This has made both flora and fauna increasingly vulnerable to extinction.
Consequences include rising global temperatures, ocean warming, increased sea levels, and more frequent extreme weather events. These shifts disturb the balance of ecosystems and natural resource availability.
Deforestation alone caused a 41% rise in carbon emissions between 1979 and 1989, as reported by Myers (1989). Climate change also disrupts natural cycles, including plant flowering seasons, crop calendars, and animal migrations.
Over 1,200 bird species are now threatened with extinction. Since the early 1800s, more than 100 species have disappeared, with alarming losses in honeybee populations due to 'Colony Collapse' and rising whale mortality rates linked to climate change.
Exotic species introduced—intentionally or accidentally—can severely disrupt the ecological balance of native habitats. When introduced outside their native geographical ranges, these invasive species often harm indigenous flora and fauna.
They may compete for food, prey on native species, spread new diseases, or cause genetic alterations through interbreeding. In areas lacking natural predators, such species may multiply unchecked and decimate local biodiversity.
Notable examples include pythons in the Florida Everglades and lionfish in the Gulf of Mexico. Most invasive species invasions can be directly linked to human actions.
Forest fires, often triggered by rising temperatures and prolonged dry spells, are a growing threat to biodiversity. These fires occur regularly in tropical regions and cause mass displacement of territorial animals, especially birds and mammals.
The resulting habitat destruction leaves animals with no shelter, often leading to death. In 1998, fires in the Russian Federation raised water temperatures and CO₂ levels, impairing salmon spawning. Similarly, the 2019 Australian bushfires showcased the massive ecological damage wildfires can cause.
India reported over 30,000 forest fire incidents in 2019, including a major fire at the Bandipur Tiger Reserve in Karnataka, as per the India State of Forest Report.
Volcanic eruptions can wipe out entire ecosystems surrounding the eruption zone. The sudden and massive release of ash and lava destroys all plant and animal life in the vicinity.
A historic example is the 1980 eruption of Mount St. Helens in Washington, USA. The blast and subsequent ashfall devastated nearby agriculture—damaging crops like wheat, apples, and alfalfa—and killed an estimated 1,500 elk, 5,000 deer, and 12 million salmon.
Recreational hunting and unregulated trophy collection significantly impact vulnerable species. Whether for sport, aesthetic value, or monetary gain, such practices are pushing several animals toward extinction.
African elephants have lost over one-third of their population in the last decade due to poaching driven by the ivory trade. Furthermore, overharvesting of medicinal plants for local or traditional use has endangered many native species.
In Southern Cochabamba, Bolivia, around 132 plant species are used for traditional medicine. Out of these, 10 species are now under serious threat due to unsustainable harvesting.
Traditional knowledge systems have long utilized specific animals and plants for medicinal purposes. However, this demand is contributing to widespread poaching and habitat destruction.
Rhino horn is highly valued in some Asian cultures for its supposed healing properties. As a result, rhinos are now being hunted to near extinction. Another example is the endangered red sandalwood, prized for its medicinal and aromatic uses.
Red sandalwood, native to the Eastern Ghats of Andhra Pradesh, is used for treating digestive issues and blood purification. The core of the trunk is particularly valuable, leading to illegal smuggling of the species for commercial and medicinal purposes. It is currently listed as a threatened species by the International Union for Conservation of Nature (IUCN).
While natural events like volcanoes and wildfires contribute to biodiversity loss, human actions amplify their frequency and impact. Activities such as species introduction, resource overuse, and traditional medicine demand create feedback loops that degrade ecosystems faster than they can recover.
To mitigate these effects, strong conservation laws, habitat protection, and sustainable practices are essential on a global scale. The long-term preservation of biodiversity depends on harmonizing traditional knowledge with ecological responsibility.
Biodiversity plays a central role in maintaining ecological balance. Even a slight decline in species can disrupt the food chain and negatively affect overall ecosystem functioning.
Some species act as keystone components of ecosystems. When these essential species go extinct, the entire ecological network is disturbed, leading to a collapse of mutual interactions and benefits, and eventually, ecosystem malfunction.
Biodiversity underpins critical ecosystem services such as oxygen production, soil enrichment, rainfall regulation, and water retention. Forests help purify air, enrich soil with humus, attract rainfall, and provide habitats for countless species.
Destruction of ecosystems through deforestation threatens all these natural benefits. For instance, mangrove forests can store up to five times more carbon per square kilometre than mature rainforests.
Microorganisms in soil break down organic matter, making it fertile. Wetlands act as natural filters, removing toxins from water. Pollinating insects are essential for crop reproduction. If humans had to artificially replicate these services, the global cost would run into trillions of dollars—exceeding the total value of all world economies.
Human health is closely tied to ecosystem products such as food, clean water, and energy resources. Traditional medicine still forms the backbone of primary healthcare in many regions.
Medicinal plants like neem have potent healing properties and are widely used. Communities across the globe depend on naturally available resources not just for medicine, but also for cultural practices and nutrition.
Soil microorganisms play a vital role in providing nutrients essential for agricultural productivity. Different varieties of the same crop can contain significantly different nutritional profiles, influencing dietary health.
A nutrient-rich diet, supported by agricultural biodiversity, is key to maintaining a healthy population and a resilient food system.
Indigenous communities often share a sacred relationship with local biodiversity. Plants and flowers are integral to religious and spiritual rituals, particularly in the Hindu tradition.
Religions around the world emphasize the spiritual connection with nature, and the loss of biodiversity threatens these longstanding cultural ties and sacred practices.
Timber, rubber, and forest produce are major resources derived from biodiversity. Several economies, like Malaysia’s, are heavily dependent on forest-based industries.
The depletion of biodiversity directly threatens the raw material supply for numerous commercial sectors and weakens the economic foundation of entire nations.
Ecotourism is a sustainable and profitable industry rooted in biodiversity. The Great Barrier Reef alone contributes approximately $6 billion annually to Australia’s economy through tourism and recreation.
Bird sanctuaries, forests, and other natural attractions draw nature enthusiasts worldwide. If biodiversity and natural landscapes vanish, the tourism industry will suffer immense economic setbacks and disturb ecological harmony.
The cumulative impact of biodiversity loss jeopardizes the sustainability of the Earth’s surface. As natural resources deplete and ecosystems break down, the survival of humankind faces unprecedented threats.
Protecting biodiversity is not just about saving plants and animals—it's about ensuring the resilience, health, and future of human civilization.
The term biodiversity hotspot was first introduced by British ecologist Norman Myers in 1988. These are areas that are extremely rich in biodiversity, particularly with a high number of endemic species, but are also under serious threat from human activities.
Biodiversity hotspots are zones highly vulnerable to habitat loss, often due to forest encroachment or anthropogenic development. The concept of endemism refers to species that are unique to a defined geographic location, often restricted to specific ecosystems.
According to Conservation International, an area must fulfill the following two criteria to be classified as a biodiversity hotspot:
Globally, 36 biodiversity hotspots have been identified, distributed across continents based on species richness, endemism, and levels of threat. These areas harbor the majority of endangered species and serve as ecological treasure troves.
Highlights by region include:
All biodiversity hotspots are highly threatened due to population growth and unsustainable development practices within or surrounding these regions.
To mitigate biodiversity loss in these ecologically sensitive areas, stringent environmental policies must be implemented. These policies should include:
Long-term sustainability of these regions depends on balancing conservation with development, ensuring biodiversity protection while meeting human needs.
The following table lists the 36 globally recognized biodiversity hotspots along with their locations:
After understanding the concept of biodiversity, its causes of loss, and hotspot regions, it is crucial to explore strategies for its preservation. The management of biodiversity loss involves various methods to protect and conserve biodiversity, ranging from individual species conservation to entire ecosystems.
Broadly, biodiversity management can be divided into two main categories:
In-situ biodiversity management refers to the conservation of species in their natural habitats. Hence, it is also called on-site conservation. This method preserves ecosystems in their original location and facilitates the natural processes of renewal and restoration.
Such management involves the identification of biodiversity-rich areas and designating them as protected areas. These zones not only conserve flora, fauna, and ecosystems but also contribute to the livelihood of local communities and serve as buffers against natural disasters and climate change.
Challenges: Protected areas often face threats due to their small size, insufficient funding, lack of trained personnel, and illegal activities such as poaching, logging, mining, and land encroachment.
Ex-situ management involves conserving species away from their natural habitats. It is also referred to as off-site conservation. This includes methods like:
Several international conventions and agreements have been ratified to encourage global biodiversity conservation:
Important Insight: Some scholars argue for sustainable exploitation over complete protection, believing that assigning economic value to biodiversity can strengthen conservation efforts (Spellerberg, 1992).