BIODIVERSITY

 Biodiversity encompasses the complexity and richness of life on our planet, from the tiniest microbe to the mightiest tree, and from the simplest ecosystem to the most intricate web of relationships.

The United Nations Environment Programme (UNEP) defines biodiversity as "the variability among living organisms from all sources, including terrestrial, marine and other aquatic ecosystems, and the ecological complexes of which they are part".

Biodiversity is the vast array of all the species of plants, animals, insects and the microorganisms inhabiting the earth either in the aquatic or the terrestrial habitats. The human civilization depends directly or indirectly upon this biodiversity for their very basic needs of survival–food, fodder, fuel, fertilizer, timber, liquor, rubber, leather, medicines and several raw materials. This diversity’s the condition for the long-term sustainability of the environment, continuity of life on earth and the maintenance of its integrity. 

Biodiversity is generally divided in terms of three fundamental and hierarchically related levels of biological organisms. These are:-

1. Genetic diversity: It includes the genetic variations within species, both among geographically separated populations and among individuals within single population.
2. Species diversity:  It involves includes full range of species from micro organisms to mammoth varieties of plants and animals, e.g. single celled viruses and bacteria etc. and multi-cellular plants, animals and fungi.
3. Ecosystem diversity: It studies variation in the biological communities in which species live, exist and interact.

Because genes are parts of species, and the species make up ecosystems- the concept of biodiversity reflects an interrelationship among its three components. Biodiversity is distributed uniformly across the globe. It is substantially greater in some areas than in the others.

Loss of Biodiversity

Biodiversity is diminished or destroyed in a number of ways either by natural changes or by human disruption. The loss of even a single species is considered as a tragedy as each form of life is a natural storehouse of irreplaceable substances the genetic materials (Ehrlich & Ehrlich, 1982). As species become extinct, the fine balance of nature is disturbed to great extent. The loss of even a single species can alter a food chain/food web, i.e. ecosystem disruption, and upset the delicate balance between one species that preys upon another.

Natural Causes

Species arise through processes of mutation, isolation, and natural selection. Evolution can proceed gradually over millions of years or may occur in large jumps when new organisms migrate into an area or when environmental conditions change rapidly. In a general way, the species that are replaced by their descendants are not completely lost; they just transform into a new species that means their genes will probably still survive in its offspring.

Climate change, flood, earthquake are the main natural causes of loss of biodiversity.

Human-Caused Extinction

Man has a long history of dependence on biological resource hence depletion of resources is obvious. It has never been the pursuit of mankind to completely destroy other species, but in a variety of ways through ignorance or carelessness, we have reduced biological abundance and driven species into extinction. The loss of species and ecosystems extracts a high price. The water, the air, fertile soils and productive seas as a common resource are all products of healthy biological systems. The scale of human impact on the global biodiversity is huge. It is considered that man has disturbed his own life support system.

Value of Biodiversity

Each species are connected to one another, so you can say ecosystem is for everyone. Likewise plants are beneficial for each species present on earth similarly organisms also provide food for plants; we work for each other. Ecosystems and species provide an enormous range of goods and other services - immediate as well as long term, material as well as spiritual and psychological - which are vital to our well being. The values of the earth’s biological resources can broadly be classified into:-

DIRECT VALUES

          Consumptive and productive uses.

Food Resources:- Grains, vegetables, fruits, nuts, condiments, tea-coffee, tobacco, liquor, oil from plant resources; and meat, fish, egg, milk (and milk products), honey, etc. from animal resources.

Other Resources:- Medicine, fuel, timber, household accessories, fodder, fiber, fertilizer, wool, leather, paint, resin, wax, thatch. Ornamental plants, rubber, creams, silk, feathers, decorative items, etc.

INDIRECT VALUES

           Non-consumptive uses and options for the future.

1. Carbon fixing through photosynthesis, which provides the support system for species. 
2. Pollination, gene flow, etc. 
3. Maintaining water cycles, recharging ground water, protecting watersheds. 
4. Buffering from climatic extreme conditions such as flood and drought; 
5. Soil production and protection from erosion; 
6. Maintaining essential nutrient cycles, e.g. carbon, nitrogen, and oxygen and others. 
7. Absorbing and decomposing pollutants, organic wastes, pesticides, air and water pollutants; 
8. Regulating climate at both macro and micro levels; 
9. Preserving recreational, aesthetic, socio-cultural, scientific, educational, ethical and historical values of natural environments.

• Consumptive Use: Man is mostly dependent on plant and animal resources for his’ dietary requirements. A major share of our food comes from domesticated crops and animals. Still we derive major of food from wild species. A large section of human population is dependent on food, which we gather from seas, and oceans that is harvested from free roaming wild organisms.  Unfortunately, deforestation, hunting and clearing of forests, grazing and expansion of agricultural lands removes potentially valuable food species and the wild ancestors of our domestic crops.
• Productive Use: Trade and commerce industry is very largely dependent on forests. Besides, timber, firewood, paper pulp, and other wood products, we get many valuable commercial products from forests. Many wild species e.g. milkweeds, etc. are also being investigated as a source of rubber, alkaloids, and other valuable organic chemicals.
• Medicine: Many medicinal and aromatic plants are being exploited in the wild to tap their potential for different ailment cure in the field of drug extraction. Like Himalayan forests serve as a storehouse of medicinal herbs, which are presently being used to cure many diseases. Animal products are also sources of drugs, analgesics pharmaceuticals, antibiotics, heart regulators, anticancer and ant parasite drugs, blood pressure regulators, anticoagulants, enzymes, and hormones. 
• Cultural Benefits: A particular species or community of organisms may have emotional value for a group of people who feel that their identity is inextricably linked to the natural components of the environment that shaped their culture. This may be expressed as a religious value, or it may be a psychological need for access to wildlife. In either case, we often place a high value on the preservation of certain wild species. Some tribal community are very connected to plants and animals. Like we can see the example of Chipko Andolan which was related to not cut down the plants. Similarly, in Jharkhand states tribes are very connected to plants and animal species the tribes of Jharkhand has started the campaign naming 'Jungle Bachao Abhiyan'. 

That's how species are important for a balanced ecosystem.