Biodiversity and its values.

2010 - International Year of Biodiversity:

2010 has been declared as the 'International Year of Biodiversity' by UNO. 'Biodiversity is life, celebrate it'  is the slogan. In this context, its better to know what is biodiversity and why so much of importance is given to it?   

What is Biodiversity?

According to the International Convention on Biodiversity (CBD) Biodiversity is the variability among living organisms from all sources including terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part; including diversity within species, between species and of ecosystems. In a broad sense, it includes the entire life on earth.

            In the emerging age of biotechnology, biodiversity is the crucial resource for nations to  thrive.   Realising this, there has been global efforts to evolve internationally acceptable norms for conservation, sustainable utilization and equitable sharing of benefits of biodiversity, since the Earth summit of 1992. The CBD, which has been ratified by more than 170 signatory nations including India, was the starting point of such a development. The recent enactment of the Biological Diversity Act – 2002 which ascertains the sovereign rights of the nation  over its biodiversity  resources was an important step taken by India towards  fulfilling its commitment to the objectives of CBD.

Biodiversity can be understood and measured at various levels of biological organisation.  Accordingly, it is divided into three types.

Genetic diversity: Genetic diversity refers to the variations or differences  present among the  individuals of the same species and it  represents the diversity in the populations of the same species.  Such variations are due to the differences in genetic makeup of individuals. In other words, every individual plant or animal is unique in its genetic characteristics. 

As a result of genetic diversity, many varieties are seen within plant species like rice, mango,  brinjal, etc. Ex. Mango has many wild and cultivated varieties like thothapuri, mundappa, ratnagiri, badami, neelam, appemidi, etc. More than 80,000 traditional varieties existed in rice all of which belong to the same species called Oryza sativa.

Similarly, many  breeds are found in  animals like cattle,  sheep, bulls, cocks and others. Ex. Hallikar, malenadu gidda, jersey are some of the cattle breeds which are different from each other.

Species diversity:       Species diversity refers to the number of different species present in a geographical region or a habitat. It is the measure of diversity at the level of species.

Species is a group of similar looking organisms. Ex. All humans together makeup one species called Homo sapiens. All breeds of cattle together form  one species. All those different variety of mangoes constitute a single species called Mangifera indica.

As species represents the easily recognisable units of biological organisation, species diversity is the easiest method of measuring biodiversity.

Ex. About 1.7 million species exist on earth.  Species diversity of India is about 1.2  lakh and of Karnataka is about 22,000.

Ecosystem or Habitat diversity:  Ecosystem or Habitat diversity refers to the variety of ecosystems or habitats occurring in a geographical region.

An ecosystem or habitat is the assemblage of many different species living in interaction with each other and also with the surrounding non-living factors. Waterscapes and landscapes like ponds, rivers, forests,  grasslands, deserts, mountains, etc.  are examples for distinctive ecosystems. 

Each of these ecosystems has its own set of species. The set of species found in a pond ecosystem is different from the set of species in a forest. Therefore, biodiversity increases with types of ecosystems. In other words, a region supporting many different ecosystems or habitats will be richer in biodiversity than another area where only one or two ecosystems exist.

Value of biodiversity:

Human beings are traditionally dependent on plants, animals and microbes in their surroundings for various purposes such as food, medicine, cloth, cosmetics, dyes, fiber, pesticides, building materials and household articles of daily use. Modern methods of biodiversity exploitation occur on a larger scale and can be seen in industries like paper, textile, pharmaceuticals, food processing and others.

In addition to these direct materialistic benefits, biodiversity also provides invaluable indirect services to our environment such as maintaining the water cycle,  production of oxygen, cooling the environment, increasing soil fertility, etc.   All these indirect ecological benefits of biodiversity are together called ecosystem services.

All these various values of biodiversity can be classified as follows:

Consumptive use value: This refers to direct use or utilization of biodiversity by communities for their various daily existence needs like food, medicine, fuel wood, building material, clothing and others.  This type of direct use is more prevalent in rural and tribal localities where communities are still live close to nature.

For example, the tribals collect a  large number of roots, tubers, fruits and  fishes and use them as food. They also use medicinal plants to treat their common ailments.

Food and medicine are two very important consumptive products provided by biodiversity.

·         About 3000 species of plants are used world wide as sources of food. Among them, about 200 species are domesticated, developed by plant breeding and used in agricultural practices. Among these, the four major crop species rice, wheat, maize  and potato provides more than 50% of the food requirement of the world population. A few dozen animals, mainly mammals, are used in animal husbandry practices.

·         Traditional crop varieties or land races are another important source of food. These are crop varieties adapted to local conditions and used widely in traditional agriculture. For example over 30,000 traditional varieties of rice were cultivated in India. Land races also provide useful genes for the improvement of modern cultivars.

·         Local people also use a wide range of wild plants and animals as food. Many wild plants provide edible tubers, fruits, nuts and green leafy vegetables. Many birds, fishes, crabs etc. are caught from natural habitats and eaten. These species can be developed as the alternative sources of food in future.

·         According to WHO, more than 20,000 species of medicinal plants are used in the traditional medical practices all over the world, on which 80% people in developing countries are dependent.

Productive use value: This refers to production of marketable goods or products from biodiversity sources. In other words, biodiversity can be  used to gain monetary returns. For this reason, the preservation of biodiversity is essential also for industrial growth and economic development.

A large number of commercial products are provided by biodiversity. Some examples are:

·         Several commercial food products and nutritional items are prepared from plants and animals. About 120 drugs obtained from over 90 species of plants are used in modern medicine. eg. Aspirin from Filipendula ulmaria, Digitoxin from Digitalis purpurea, Vincristin from Vinca rosea, Taxol from Taxus buccata, etc. About 8000 species of plants are used in traditional medical practices of India like Ayurveda, Sidda, Folk medicine etc. Medicinal preparations  made from these plants  are marketed  by several companies.

·         Many species of plants are the source of commercial commodities like timber, canes, fiber, useful chemicals, fuel etc. Teak, Rose wood, Sal etc are the important timber yielding trees. Several species of Calamus are the source of Cane used in the making of furniture  and other items. A variety of handicrafts, baskets, mats  and other useful items are made from bamboo. 

·         Ornamental plants  are important commercially and contribute significantly to international trade. Both whole plants and cut organs like flowers, leaves have ornamental value. Ex.: orchids, cacti, cycads, tulips, anthuriums, etc.

Social and Ethical values: Biodiversity also has social and ethical values which are of indirect nature. Many traditional societies believe that all forms of life are sacred and have the right to exist on earth. They also consider that protecting them is a moral responsibility. This philosophy has manifested in the practice of  worshiping nature and its components like plants and animals.

Many species of plants and animals are considered as sacred based on religious faith grounds and are employed in the religious ceremonies and practices. Such species are called sacred species. Ex. Tulasi or holy basil is considered sacred by Hindu’s and used in worships. Similarly, plants like dhruva, bilva, atti or fig, ala or banyan, ashwatha or pipul, etc. are also considered as sacred trees and worshipped by planting near temples.

Several species of aquatic animals like fishes, crocodiles, turtles etc., are regarded as sacred and and protected in sacred landscapes like ponds and rivers associated with religious structures like temples.

Traditional societies worship and protect entire landscapes comprising of forests, rivers, ponds, lakes etc. considering that they are the abodes of gods. Such traditionally managed landscapes with ethical or religious significance are called sacred landscapes. Patches of forest protected on religious faith grounds are called sacred groves. They are locally called by different names such as devara kadu, pavitra vana and bana. Sacred groves are commonly found in the western Ghats region and in the north eastern states of India.

Aesthetic value: Aesthetic value of biodiversity exists in its inherent quality of adding or enhancing the beauty of our environment. Plants with their attractive flowers, butterflies and moths with their colourful wings, birds with their melodious chirping sounds make our nature beautiful.

A flower garden or park adds beauty to a town or city and serves as a common place where children and people can relax.  A lake provides space for recreational activities like boating and attracts tourists. 

Option value: Option value of biodiversity refers to its potential to  provide economic and other benefits to human society at some point in the future.

A plant or animal which at present has  no direct economic value may prove to be having a useful  medicinal chemical or gene sometimes in the future. For example, until it was discovered that an anti-cancerous medicine named taxol is present in its bark, the pacific yew plant (Taxus) was of no value.

   Option value suggests that every species has to be protected, irrespective of the fact that whether it is useful or not at present. It is impossible predict at present which species will be of greatest use in the future.

Global Biodiversity:

The world is  estimated to have 5 to 50 million species of organisms.  However, it has not been possible to identify and record all these species. So far,  only  about 1.7 million species have been described globally. The distribution of these species in the world is highly uneven. About seven per cent of the world’s total land area including the tropical region is home to half of the world’s species.

The top 12 countries which are highly rich in biodiversity and considered as the mega-diversity nations are Australia, Brazil, China, Columbia, Ecuador, Indonesia, Madagascar, Malaysia, Mexico, Peru, Zaire and India.

India as a mega-diversity nation:

India contains a great wealth of biological diversity in its forests, its wetlands and in its marine areas.  It has over 1,20,000 species which is over 7% of the global diversity of about 17,00,000 species. Owing to this species richness, India is considered as one among the 12 mega-diversity nations of the world. 

GROUP	GLOBAL DIVERSITY	INDIA	ENDEMICS
Prokaryotes Fungi Algae Angiosperms Insects Molluscs Fishes Amphibia Reptiles Birds Mammals	4,800 69,000 26,900 2,50,000 8,00,000 50,000 23,000 4,200 6,300 9,000 5400	850 23,000 2,500 17,500 60,000 5,050 2,500 204 446 1,250 372	- - - 5,750 - - - 110 187 70 44

Table 1. Comparison between the number of species in India and the World.

Some of the important features of biodiversity of India are:

·         The western Ghats and the Eastern Himalaya are the two regions in India which are particularly rich in biodiversity. These two are added among the 34  biodiversity hotspots identified all over the world. Hotspots are areas particularly rich in total biodiversity which consists of a high percentage of endemic species.

·         India is one of the 12 centres of origin of cultivated plants. It  is a centre of diversity of crop plants and is the  homeland of 165 cultivated species and 320 wild relatives of crop plants.

·         India has 5 world heritage sites, 12 biosphere reserves, and 6 Ramsar wetlands. Amongst the protected areas, India has 88 national parks and 490 sanctuaries covering an area of 1.53 lakh sq. km.

·         About 33% of the country’s recorded plants are endemic which means they are found exclusively in India and no where else in the world. About 62% of the known amphibian species and 50% of the lizards are endemic with the majority occurring in the Western Ghats.