NCERT

Conserving Biodiversity of the Country      

India is one of the 12 mega biodiversity countries in the world. The country is divided into 10 biogeographic regions. The diverse physical features and climatic situations have formed ecological habitats like forests, grasslands, wetlands, coastal and marine ecosystems and desert ecosystems, which harbour and sustain immense biodiversity. Biogeographically, India is situated at the tri-junction of three realms – Afro-tropical, Indo-Malayan and Paleo-Arctic realms, and therefore, has characteristic elements from each of them. This assemblage of three distinct realms makes the country rich and unique in biological diversity.

The country is also one of the 12 primary centres of origin of cultivated plants and domesticated animals. It is considered to be the homeland of 167 important plant species of cereals, millets, fruits, condiments, vegetables, pulses, fibre crops and oilseeds, and 114 breeds of domesticated animals.

About 4,900 species of flowering plants are endemic to the country. These are distributed among 141 genera belonging to 47 families. These are concentrated in the floristically rich areas of North-East India, the Western Ghats, North-West Himalayas and the Andaman and Nicobar Islands. These areas constitute two of the 18 hot spots identified in the world. It is estimated that 62 per cent of the known amphibian species are endemic to India of which a majority is found in Western Ghats.

Approximately 65 per cent of the total geographical area has been surveyed so far. Based on this, over 46,000 species of plants and 81,000 species of animals have been described by the Botanical Survey of India (BSI) established in 1890 and Zoological Survey of India (ZSI) established in 1916, respectively. This list is being constantly upgraded, specially in lower plants and invertebrate animals. The Forest Survey of India established in 1981 assess the forest cover with a view to develop an accurate database for planning and monitoring purposes.

  • Conservation and sustainable use of biological resources based on local knowledge systems and practices is ingrained in Indian ethos. The country has a number of alternative medicines, like Ayurveda, Unani, Siddha and Homeopathic systems which are predominantly based on plant based raw materials in most of their preparations and formulations. Herbal preparations for various purposes including pharmaceutical and cosmetic purposes form part of the traditional biodiversity uses in India.
  • Approximately, 4.2 per cent of the total geographical area of the country has been earmarked for extensive
    in-situ conservation of habitats and ecosystems. A protected area network of 85 national parks and 448 wildlife sanctuaries has been created. The results of this network have been significant in restoring viable population of large mammals such as tiger, lion, rhinoceros, crocodiles and elephants.
  • The Indian Council of Forestry Research and Education (ICFRE) has identified 309 forest preservation plots of representative forest types for conservation of viable and representative areas of biodiversity. Out of these plots, 187 area in natural forests and 112 are in plantations, covering a total area of 8,500 hectares.
  • Six significant wetlands of India have been declared as “Ramsar Sites” under the Ramsar Convention. Under the World Heritage Convention, five natural sites have been declared as “World Heritage Sites”.
  • To conserve the representative ecosystems, a Biosphere Reserve Programme is being implemented. Twelve biodiversity rich areas of the country have been designated as Biosphere Reserves applying the UNESCO/MAB criteria. These reserves aim at conserving the biological diversity and genetic integrity of plants, animals and microorganisms in their totality as part of the natural ecosystems, so as to ensure that self-perpetuation and unhindered evolution of the living resources.

Conserving Biodiversity of the Country      

Biodiversity of India

  • Biodiversity of India

India has a rich and varied heritage of biodiversity, encompassing a wide spectrum of habitats from tropical rainforests to alpine vegetation and from temperate forests to coastal wetlands. India figured with two hotspots – the Western Ghats and the Eastern Himalayas.

India contributes significantly to latitudinal biodiversity trend. With a mere 2.4% of the world’s area, India accounts for 7.31% of the global faunal total with a faunal species count of 89,451 species.

Few month ago we have started YouTube Channel Science World please visit for daily science fact video

Bio-geographical regions of India

India has two major realms called the Palaearctic and the Indo-Malayan, and three biomass, namely the tropical humid forests, the tropical dry/deciduous forests, and the warm desert/semi-deserts. India has ten biogeographic regions including the Trans-Himalayan, the Himalayan, the Indian desert, the semi-arid zone(s), the Western Ghats, the Deccan Peninsula, the Gangetic Plain, North-East India, and the islands and coasts. India is one of the 12 centres of origin of cultivated 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. India’s record in agro-biodiversity is equally impressive. There are 167 crop species and wild relatives. India is considered to be the centre of origin of 30,000-50,000 varieties of rice, pigeon-pea, mango, turmeric, ginger, sugarcane, gooseberries etc and ranks seventh in terms of contribution to world agriculture.

what is Gradient in biodiversity

Gradients in Biodiversity       (please subscribe and share our YouTube channel Science World)                  

Latitudinal Gradients in Biodiversity

The word ‘tropical’ usually evokes images of a dense jungle packed with all sorts of different creatures, or a coral reef full of fishes of many different colours. However, ‘the tropics’, i.e. the zone extending approximately 30º north and south of the Equator (Pringle 2000), includes also huge extents of desert and savannah which appear, on the contrary, to contain low numbers and diversities of living organisms.

Are then, the tropics, more biologically diverse than other climatic zones? In fact, this is the most universally accepted and oldest recognized pattern in ecology. The tropics have extraordinarily high species richness or, viewed from a different perspective, areas outside the tropics have extraordinarily low species richness (Blackburn and Gaston 1996).

Generality of latitudinal diversity gradients

Despite this recognition of the generality of latitudinal diversity gradients, our knowledge is biased towards some taxonomic groups, regions and ecosystems. First, studies have been biased towards vertebrates, which make up less than 5% of species on Earth. For example, many mammals peak in species richness in the tropics (Kaufman 1995), while some insect groups show reversed latitudinal gradients (Kouki et al. 1994).
Second, diversity gradients described for the northern hemisphere seem to be invalid for the southern hemisphere (Platnick 1991, Boyero 2002). For example, terrestrial vertebrates are more species rich in Central America than North America, but that is not the case in tropical versus temperate Australia (Schall and Pianka 1978). Species richness of Odonata per unit area is similar in tropical and temperate South America, while it is about 29 times greater in Central America than in North America. The so-called ‘boreal bias’ (Platnick 1991) exists because the vast majority of studies have been performed by ecologists from North America and Europe.

Third, most of the available information comes from terrestrial or marine ecosystems, while fresh waters have received little attention, even though they contain 20% of the Earth’s vertebrate species (Rohde 1998). Nevertheless, available data show that freshwater fish and macro invertebrates are more diverse in the tropics. For example, the number of fish species in tropical lakes far exceeds that of temperate lakes (e.g. 1450 species in the lakes Victoria, Tanganyika and Malawi versus 212 species in the North American Great Lakes and Lake Baikal; Rohde 1998).

A similar pattern is found in rivers (e.g. 2000 species in the Amazon and 700 in the Congo, versus 250 species in the Mississippi and 70 in the Danube, Pringle 2000). Some stream macro invertebrates are more diverse in the tropics in Australia  and America (e.g. 25 species of Odonata and 32 of Ephemeroptera per unit area (106 km) in North America, versus 717 Odonata and 206 Ephemeroptera in Central America; Boyero 2002).

The causes for latitudinal gradients in biodiversity

The determinant of biological diversity is, clearly, not latitude per se, but the environmental variables correlated with latitude. More than 25 different mechanisms have been suggested for generating latitudinal diversity gradients, but no consensus has been reached yet (Gaston 2000).

One of the factors proposed as a cause of latitudinal diversity gradients is the area of the climatic zones. Tropical land masses have a larger climatically similar total surface area than land masses at higher latitudes with similarly small temperature fluctuations (Rosenzweig 1992). This may be related to higher levels of speciation and lower levels of extinction in the tropics Moreover, most of the land surface of the Earth was tropical or subtropical during the Tertiary, which could in part explain the greater diversity in the tropics today as an outcome of historical evolutionary processes (Ricklefs 2004).

The higher solar radiation in the tropics increases productivity, which in turn is thought to increase biological diversity. However, productivity can only explain why there is more total biomass in the tropics, not why this biomass should be allocated into more individuals, and these individuals into more species (Blackburn and Gaston 1996). Body sizes and population densities are typically lower in the tropics, implying a higher number of species, but the causes and the interactions among these three variables are complex and still uncertain (Blackburn and Gaston 1996).

Higher temperatures in the tropics may imply shorter generation times and greater mutation rates, thus accelerating speciation in the tropics (Rohde 1992). Speciation may also be accelerated by a higher habitat complexity in the tropics, although this does not apply to freshwater ecosystems. The most likely explanation is a combination of various factors, and it is expected that different factors affect differently different groups of organisms, regions (e.g. northern versus southern hemisphere) and ecosystems, yielding the variety of patterns that we observe.

The importance of understanding latitudinal gradients in biodiversity
Understanding the global distribution of biodiversity is one of the most significant objectives for ecologists and bio geographers (Gaston 2000). But, beyond purely scientific goals, this understanding is essential for applied issues of major concern to humankind, such us the spread of alien invasive species, the control of diseases and their vectors, and the likely effects of global environmental change on the maintenance of biodiversity (Gaston 2000).

Tropical areas, usually located in developing countries, play a prominent role in this picture, as their rates of habitat degradation and biodiversity loss are exceptionally high. Just as very little information existed on ‘natural’ conditions of temperate ecosystems before they were dramatically altered, this information is very scarce today for the tropics. The difference is that, today, it is not too late to collect this information

how we can characterized Community biodiversity

  • Community Diversity (You can visit my educational YouTube channel Science World)

 Ecologists have developed ways to characterize species diversity in a given area:

  • Within-habitat diversity or alpha-diversity: refers to a group of organisms interacting and competing for the same resources or sharing the same environment. Measured as # of species within a given area.
  • Between-habitat diversity or beta-diversity: refers to the response of organisms to spatial heterogeneity. High beta-diversity implies low similarity between species composition of different habitats. It is usually expressed in terms of similarity index between communities (or species turnover rate) between different habitats in same geographical area (often expressed as some kind of gradient).
  • Geographical diversity or gamma-diversity: This term is used for the rate of turnover or replacement of species b/w similar habitat in different geographical areas. Such as difference in species. Diversity of habitat are the total landscape or geographical area is called GAMA DIVERSITY.

world heritage site in India

Science World

The Buddhist caves at Ajanta contain some of India’s most magnificent paintings. The 29 caves were excavated beginning around 200 BC, but they were abandoned in 650 AD in favour of Ellora. Five of the caves were temples and 24 were monasteries, thought to have been occupied by some 200 monks and artisans. The Ajanta Caves were gradually forgotten until their `rediscovery’ by a British tiger-hunting party in 1819.

The Buddhist, Hindu and Jain caves at Ellora, carved between 600 and 1000 AD, include 34 monasteries and temples dug side by side in the wall of a high basaltic cliff not far from Aurangabad. It seems that the caves were started by the Buddhist builders of Ajanta when they deserted that site, but later non-Buddhist caves were created simultaneously in a flowering of creative competition between the different religions.

The Buddhist caves at Ajanta contain some of India’s most magnificent paintings. The 29 caves were excavated beginning around 200 BC, but they were abandoned in 650 AD in favour of Ellora. Five of the caves were temples and 24 were monasteries, thought to have been occupied by some 200 monks and artisans. The Ajanta Caves were gradually forgotten until their `rediscovery’ by a British tiger-hunting party in 1819.

The Buddhist, Hindu and Jain caves at Ellora, carved between 600 and 1000 AD, include 34 monasteries and temples dug side by side in the wall of a high basaltic cliff not far from Aurangabad. It seems that the caves were started by the Buddhist builders of Ajanta when they deserted that site, but later non-Buddhist caves were created simultaneously in a flowering of creative competition between the different religions.

What are possible level of Biodiversity? (with examples)

  • Level of Biodiversity (For more Educational topics click on Science World)

Biodiversity is said to have three level or components that are:

  1. Ecological diversity: Indian ecosystem biodiversity is described at each three levels (biogeographical region, biotic province &biome.) largest identified ecosystem is biogeographical zone. The vast area covered by biogeographical zone contains a wide diversity of smaller units called biotic provinces. Finally in each biotic province various kinds of biomes. Biome classification follows the following terminology, distinguishing b/w forest, grasslands, wetlands, desert and other such ecosystems on the basis of their physical appearance & dominant biotic or Abiotic element. Vast range of terrestrial and aquatic environment on earth has been classified into no. of ecosystem. Such as: TROPICAL RAIN FOREST, GRASSLAND & WETLANDS.
  2.  Species diversity: It refers to variety of species in a region. With increase in fortunately, genetic diversity can be estimated by species diversity, and this has become the standard unit of measurement in most biodiversity surveys. Species have the advantage of being natural biological divisions and easily identifiable; their diverging appearances were the basis by which they were classified in the 18th century, and modern phylogenetic techniques more often than not produce species divisions similar to those of classical taxonomic divisions. For many groups of organisms, such as birds and flowers, public interest means that identification of many species is already known by large numbers of people. The degree of genetic variability at the species level, and indeed at any taxonomic level, can be maximized by taking species that differ by one another by as many characters as possible. If these characters represent different genetic elements, then the divergent species should represent greater genetic diversity.
  3. Genetic diversity

It refers to the variation of genes in species. Some argue that the fundamental unit of biodiversity is the gene. Genetic diversity is the degree of variability of the genetic material of an organism. Species are defined by the differences in their genes. High genetic diversity indicates populations that can more easily adapt to changing situations and environments, and also a greater assortment of materials that can be found, increasing the chances of finding a useful compound.  However, exact assessment of genetic diversity is both time-consuming and prohibitively expensive, requiring modern laboratories and expensive chemicals. We have so far been able to account for all the genes in just one species of bacteria! Realistically, investigators could only examine a minute fraction of the genetic diversity to be found using this approach, and time is often a constraint.

What is Biodiversity and its types

Biodiversity Introduction by Science World

‘Biodiversity’ is a term frequently used. It is short for ‘biological diversity’. A concise definition of biodiversity is “the variety of life on earth”. Biodiversity is an over-arching concept which includes wildlife, habitats and conservation. Biodiversity is important to us for aesthetic and even spiritual reasons but also for practical and utilitarian ones. There is a widespread and deep concern for our countryside, wildlife and habitats as shown by the huge membership of wildlife and conservation organisations.

As we know that biology is the study of living organisms or living things. It is a combination of two words ‘bios’ which means life and ‘logos’ means happening. It deals with all aspects of life in which different types of species involved. As environmental science is a vast field which deals with all types of living things such as plants, animals or insects etc. There are different branches of environmental science one of them is biodiversity. The study of variation of different living organisms such as plants and animals in a specific area for the sake of food, living, and shelter is called as biodiversity.

Biological diversity or biodiversity refers to the variety of life forms: the different plants, animals and microorganisms, the genes they contain, and the ecosystems they form. This living wealth is the product of hundreds of millions of years of evolutionary history. The process of evolution means that the pool of living diversity is dynamic: it increases when new genetic variation is produced, a new species is created or a novel ecosystem formed; it decreases when the genetic variation within a species decreases, a species becomes extinct or an ecosystem complex is lost. The concept emphasizes the interrelated nature of the living world and its processes.

Biological diversity is usually considered at three different levels: genetic diversity, species diversity and ecosystem diversity.

Genetic diversity refers to the variety of genetic information contained in all of the individual plants, animals and microorganisms. Genetic diversity occurs within and between populations of species as well as between species. Species diversity refers to the variety of living species.

Ecosystem diversity relates to the variety of habitats, biotic communities, and ecological processes, as well as the tremendous diversity present within ecosystems in terms of habitat differences and the variety of ecological processes.

At the ecosystem level, biodiversity provides the conditions and drives the processes that sustain the global economy – and our very survival as a species. The benefits and services provided by ecosystems include:

The activities of microbial and animal species – including bacteria, algae, fungi, mites, millipedes and worms – condition soils, break down organic matter, and release essential nutrients to plants. These processes play a key role in the cycling of such crucial elements as nitrogen, carbon and phosphorous between the living and non-living parts of the biosphere.

Plant species purify the air and regulate the composition of the atmosphere, recycling vital oxygen and filtering harmful particles resulting from industrial activities.