The importance of biodiversity can be seen in the ways it has contributed to the development of human culture, while human communities have also played a significant role in shaping biodiversity at the genetic, species, and ecological levels.

Biodiversity has various ecological roles. Many species perform essential functions in ecosystems, such as capturing, storing, and utilizing energy, producing and decomposing organic materials, participating in cycles of water and nutrients, fixing gases in the atmosphere, and regulating the climate. These functions are crucial for maintaining soil fertility, reducing pollution, protecting land, water, and air resources, and ensuring ecosystem stability. Therefore, the preservation and conservation of biodiversity are essential for the well-being of both human communities and the natural environment.

Biodiversity is fundamental to all ecosystem services on the planet, providing a wide range of benefits to human societies and the natural environment.

One important category of ecosystem services is provisioning services, which include the products obtained from biodiversity such as food, fiber, fuelwood, and pharmaceuticals. Biodiversity, including various plants, animals, and microorganisms, is the source of many of these products. For example, cereals and fish provide us with vital sources of nutrition, while cotton and wool provide fibers for clothing. Additionally, biodiversity is the source of many medicinal products, such as neem and tulsi. Thus, the preservation and conservation of biodiversity are essential for maintaining these essential provisioning services and ensuring the well-being of human societies and the natural environment.

Biodiversity provides a wide range of services to human societies and the natural environment, including regulating services, supporting services, and social and cultural services.

Regulating services involve biodiversity’s role in regulating local and global climate, managing the levels of oxygen, carbon dioxide, and other gases, maintaining freshwater quality through vegetation, and absorbing carbon as carbon sinks. These services are crucial for maintaining life and life processes on the planet.

Supporting services include biodiversity’s role in pollination, nutrient cycling and recycling, and greenhouse gas reduction through sequestration.

Social and cultural services include biodiversity’s provision of aesthetic pleasure, recreational opportunities, and encouragement of tourism. Many communities and cultures have co-evolved with the surroundings and resources provided by a biologically diverse environment. Therefore, biodiversity also plays an important social role.

The services provided by biodiversity include recreation, relaxation, tourism (especially ecotourism), art, design, inspiration, spiritual experiences, and a sense of place. Thus, the preservation and conservation of biodiversity are crucial for maintaining these important services and ensuring the well-being of both human societies and the natural environment.

Biodiversity plays an important role in maintaining food webs by supporting complex and stable food chains. Higher diversity in ecosystems provides more options for species to eat, increasing their chances of survival and resulting in more stable food webs and chains.

Additionally, biodiversity is critical to scientific research, education, and monitoring. For instance, it helps researchers to discover new genetic materials through gene pools. Biodiversity provides a deeper understanding of the functioning of life and the role each species plays in sustaining ecosystems, of which humans are also a part. Therefore, biodiversity is essential for scientific research, education, and monitoring, as well as for the well-being of both human societies and the natural environment.

Types of Biodiversity:

Biodiversity can be classified into three types based on its three components: genes, species, and ecosystems.

Genetic diversity is the diversity of genes within a species that allows some species to survive disruptions. This results in the existence of a variety of beautiful butterflies, roses, corals, and fruits with different hues, sizes, and shapes.

Species diversity refers to the variety of species within a particular geographic region. Species that are different from one another do not naturally interbreed. However, closely related species may share similar hereditary characteristics. For example, humans and chimpanzees share about 98.4% of their genes. Species diversity can be measured by species richness, which is the number of different species in a unit area, and species evenness, which refers to the relative abundance of different species in an area.

Ecosystem or community diversity refers to the diversity of different biological communities or ecosystems, such as forests, deserts, lakes, and corals, in a region or on the earth. As ecosystems change, species best adapted to those changes become predominant. Thus, biodiversity also depends on the nature of the ecosystems.

Degree of Biodiversity:

The measurement of biodiversity was pioneered by Whittaker. Biodiversity can be assessed using two main components: Species Richness and Species Evenness.

Species Richness measures the number of species present per unit area in a region or community. It has three components:

Alpha diversity: Refers to the diversity of species within a specific area or ecosystem and is usually expressed as the number of species in that ecosystem.

Beta diversity: Compares the diversity of species between two or more ecosystems, typically measured as the change in the number of species between the ecosystems.

Gamma diversity: Measures the overall diversity for different ecosystems in a region. Gamma diversity is subjective due to different perceptions about the boundaries of the region.

Biodiversity Degradation:

The planet’s biological wealth is declining at an alarming rate. According to the IUCN Red List, 784 species have gone extinct in the last 500 years, including 338 vertebrates, 359 invertebrates, and 87 plants. Over the past two decades, more than 30 species have been lost. The Living Planet report presents the following findings:

The rate of species extinction is up to 100 to 1000 times higher than the natural rate, with up to 1000 species becoming extinct per 10,000 species in 100 years.

The Living Planet Index, which measures biodiversity abundance levels, indicates a persistent downward trend. Monitored species populations have declined by an average of 58% since 1970.

Tropical forests have experienced a 40% decline in species since 1970, while temperate grasslands have seen an 18% decline, and freshwater habitats have witnessed an 81% decline in species populations since 1970.

Declining Biodiversity and Reasons:

Habitat loss and fragmentation are primary drivers of animal and plant extinction. These phenomena result from changes in land use, such as the conversion of natural ecosystems into cropland, urbanization, infrastructure development (e.g., roads and railways), and mining activities. The Living Planet report notes that wetlands have declined by about 30% over the last 40 years, mainly due to reclamation for agriculture and urbanization. Additionally, approximately 50% of tropical and subtropical forests and 45% of temperate grasslands have been converted for human use. Pollution also degrades many habitats, further threatening species survival. Fragmentation of large habitats into smaller fragments due to human activities affects mammals and birds that require large territories and species with migratory habits, leading to declines in their populations.

Over-exploitation of species is another major cause of biodiversity loss. Unsustainable use of ecosystems, including over-hunting or poaching of species, overfishing, and overharvesting of plant products, can lead to rapid declines in biodiversity. Human consumption patterns are often responsible for this unsustainable exploitation of natural resources. Many species that have become extinct in the last five centuries, such as Steller’s sea cow and passenger pigeon, were over-exploited by humans.

The introduction of non-native species can have a significant negative impact on native species by competing with them for resources, introducing new diseases, interbreeding with native species, and disrupting food chains and the environment. For example, the Water hyacinth was brought to India by the British for ornamental purposes, but it has since become an invasive species that clogs waterways and harms aquatic life.

Pollution, such as excess fertilizers from farmland, chemicals from urban and industrial runoff, and oil spills, can accumulate in natural water bodies, leading to the death of animals and disruption of ecosystems. Air pollution from industries and vehicles can also harm bird populations in urban areas.

Global climate change is a growing threat to biodiversity, as changes in the timing of flowering and migration and shifts in species distribution patterns have already been observed around the world. These changes can disrupt food chains and other ecological interactions in which different species have evolved to depend on each other.

Calamities like flood, drought, and drastic man-made changes also result in decline of Biodiversity.