Environmental Studies - Biodiversity
Biodiversity, a shortened form of Biological diversity, refers to the existence of number of different species of plants and animals in an environment.
The Convention on Biological Diversity (1992) of the United Nations gives a formal definition of biodiversity in its Article 2: "Biological diversity means the variability among living organisms from all sources including, inter alia, terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems."
Biodiversity is also defined as the existence of variability among living organisms on the earth, including the variability within and between species, and within and between ecosystems.
Species Diversity
Species diversity refers to the variety of different species of plants, animals, fungi, and organisms that are present in a region. It is estimated that there are above 30 million species on the earth. Species diversity is a part of diversity. Even within a small pond, we can notice a great variety of species. Species diversity differs from ecosystem to ecosystem. For example, in a tropical ecosystem more diversity is found than in temperate ecosystem. The most diverse group of species is invertebrates - animals without backbones.
At present, conservation scientists have been able to identify and categorize about 1.8 million species on earth. Many new species are being identified. Areas that are rich in species diversity are called ‘hotspots’ of diversity.
Genetic Diversity
It is the variation in genes that exists within a species. Genetic diversity corresponds to the variety of genes contained in plants, animals, fungi, and micro-organisms. It occurs within a species as well as between species. For example, poodles, German shepherds and golden retrievers are all dogs, but they all are different in look, color, and abilities. Each human being is different from all others. This genetic variability is essential for a health breeding of a population of species.
The diversity in wild species make the ‘gene pool’ from which crops and domestic animals have been developed over thousands of years.
Ecosystem Diversity
It is the diversity of ecosystems, natural communities, and habitats. In other words, ecosystem diversity refers to the variety of ways that species interact with each other and their environment. Tropical or temperate forests, grasslands, hot and cold deserts, wetlands, rivers, mountains, and coral reefs are instances of ecosystem diversity.
Each ecosystem corresponds to a series of complex relationships between biotic (living) and abiotic (non-living) components.
Value & Productive Use of Biodiversity
The importance of biodiversity is second to none. It boosts the ecosystem of productivity where each species, irrespective of their size, have an important role to play. Greater diversity in species ensure natural sustainability for all life forms. Hence, there is a need to preserve the diversity in life on the earth.
According to the UN sources at least 40 percent of the world’s economy and 80 percent of the needs of the poor are derived from biological resources. In addition, the richer the diversity of life, the greater the opportunity for medical discoveries, economic development, and adaptive response to such new challenges as climate change.
Significance of Biodiversity
Environmental services from species and smooth running cycles of ecosystems are necessary at global, regional, and local levels.
Biodiversity is essential for maintaining the water cycles, production of oxygen, reduction in carbon dioxide, protecting the soil, etc. It is also essential for preserving ecological processes, such as soil formation, circulation of and cleansing of air and water, global life support, fixing and recycling of nutrients, maintaining hydrological balance within ecosystems, maintaining rivers and streams throughout the year, etc.
Biodiversity has many values such as consumptive use value, productive use value, social values, ethical and moral values.
A healthy biodiversity offers many valuable services as follows.
The more a region is rich in terms of biodiversity, better is the regulation of the different cycles. For example, forests regulate the amount of carbon dioxide in the air by releasing oxygen as a by-product during photosynthesis, and control rainfall and soil erosion.
Protects water resources from being depleted, contaminated, or polluted.
Helps in soil formation and protection.
Helps in nutrient storage and recycling.
Helps check pollution.
Contributes to climate stability.
Helps an ecosystem in recovery from unpredictable events.
Provides biological resources such as food, medicinal resources, and pharmaceutical drugs, wood products, ornamental plants, breeding stocks, etc.
Provides recreation and tourism facilities.
Helps in research, education, and monitoring.
Preservation of biological resources is essential for the well-being and long-term survival of mankind.
Productive Use Value of Biodiversity
Productive Use Value refers to the commercial value of products that are commercially harvested for exchange in formal markets.
Modern civilization is invariably a gift of biodiversity. The food we eat, the medicine we take in, the furniture we use, the industries, for example, are derivatives of biological diversity.
The agricultural crops of the present day have originated from wild varieties. Biotechnologists use the wild plants for developing new, high-yielding, and pest or diseaseresistant varieties. Biodiversity is home to original stock from which new varieties are being developed.
Similarly, all our domesticated animals came from their wild-living ancestral species. With the help of scientific breeding techniques, animals giving better yield of milk, meat, etc. are being developed. The animal products used by modern society come from the advances made in the fields of poultry farming, pisciculture, silviculture, dairy farming, etc.
Fossil fuels, considered to be pivotal in modern society, such as coal, petroleum, and natural gas are gifts of biodiversity from the geological past.
Most of the pharmaceutical drugs and medicines used in the present time are extracted from different plants.
Biodiversity provides rich storehouse for industrialists and entrepreneurs to develop new products. It provides agricultural scientists and biotechnologists with ample scope for developing new and better crops. New crop varieties are being developed using the genetic material found in wild relatives of crop plants though biotechnology.
The need of the hour is the preservation of biodiversity for industrial, economic, and above all, environmental safety. This is called ‘biological prospecting’.
