Telangana TSBIE TS Inter 1st Year Environmental Education Study Material 13th Lesson Concept, Types and Threats to Biodiversity Textbook Questions and Answers.
TS Inter 1st Year Environmental Education Study Material 13th Lesson Concept, Types and Threats to Biodiversity
Essay Questions
Question 1.
Define biodiversity and explain the levels or types of Biodiversity.
Answer:
The term biodiversity was introduced by Walter Rosen in 1986. Biodiversity is the shortened form of two words “biological” and ” diversity.” It refers to all the variety of life that can be found on Earth (plants, animals, fungi and micro-organisms) as well as to the communities that they form and the habitats in which they live.
An ecosystem includes all the living things (plants, animals and other organisms) in a given area, interacting with each other, and also with their non-living environments, such as weather, Sun and soil. It is, thus, the interaction of living and non-living things in a particular environment. A biome is a specific geographic area notable for the large community of plants and animals that live there. For example, tropical rainforests, deserts and grasslands.
Biodiversity is not merely the sum of all ecosystems, species and genetic material. Rather, it represents the variability within and among them. It can be distinguished from the expression “biological resources”, which refer to the tangible components of ecosystems. Biological resources are real entities (a particular species of bird, a wheat variety growing in a field, oak wood, etc.) while biological diversity is an attribute of life (the variety of bird species, the genetic variability of wheat around the world, forest types, etc.)
It has been estimated that more than 50 million species of plants, animals and micro – organisms exist in the world. Out of these, about 1.4 million species have been identified so far.
Each species is adapted to live in a specific environment, whether it is the mountain peaks or the depths of the seas, the polar ice caps or the tropical rain forests and deserts. All this diversity of life is confined to a one kilometre thick layer of lithosphere, hydrosphere and atmosphere which forms the biosphere.
Biodiversity Concepts
All life forms that make up biodiversity, including humans, are ultimately connected to all other life forms, and to their physical environment.
- No one living element of any ecosystem can survive independent of the others.
- Connections among living and non-living elements keep the environment functioning and healthy.
- Because biodiversity represents the inter-connectedness of all things, the effects of some causes can be surprising.
- Human impact on the environment, therefore, difectly or indirectly affects the function of other living things, and, by extension, ourselves.
Types of biodiversity :
Biodiversity includes four main types : They are :
- Species Diversity
- Genetic Diversity
- Ecosystem or Community Diversity
- Functional Diversity.
LEVELS OF BIODIVERSITY
Species Diversity :
Refers to the number of different species of plants, animals, fungi and micro-organisms that are represented in a given community. For example palm trees, elephants or bacteria. The number of species that live in a particular location is called species richness. Abundance is defined as the number of individuals of each species.
Genetic Diversity :
Refers to the total number of genetic characteristics in the genetic makeup of a species. The more genetic diversity a population has, the more likelihood the population will be able to adapt and survive. For example, poodles, german shepherds and golden retrievers are all dogs, but they all look different as they have different genes.
Ecosystem or Community Diversity :
Refers to a biological community of interacting organisms and their physical environment. Each ecosystem corresponds to a series of complex relationships between biotic (living) components such as plants and animals, and abiotic (non-living) components which include sunlight, air, water, minerals and nutrients such as air, water, and mineral soil. Examples : tropical or temperate forests, hot and cold deserts, wetlands, rivers, mountains, coral reefs, etc.
Functional Diversity :
Refers to the way species behave, obtain, food and use the natural resources of an ecosystem. In general a species rich ecosystem is presumed to have high functional divesity, because there are many species with many different behaviours. Functional diversity can be useful to ecologists trying to conserve an ecosystem or restore it when it is damaged, because knowing the behaviours and roles of species can point to gaps in a food cycle or ecological niches that ‘ack species.
Question 2.
Explain Bio-geo-graphical classification of India.
Answer:
India is a mega biodiverse country. In Greek language Mega means ‘Large’. In 1998, India has been recognised as one of the Mega bio – diversity country out of 17 countries in the world. India has been divided into 10 Bio – geographical realms and 26 Bio provinces. India is a land of forests, grasslands,, oceans, wet lands, coastal regions, marine eco system etc.
India is a land of 167 plant species of millets, fruits, vegetables, pulses etc. There are nearly about or more than 100 domestic species, 5, 000 flowering plants, 62% of amphibians. Totally there are 46,000 flora and 81,000 fauna species.
| BIO-GEOGRAPHIC ZONES IN INDIA | ||
| Bio-geo-graphiq zones | Biotic provinces | Types of species (plapts and animals) |
| 1. Trans-Himalaya | Ladakh mountains, Tibetan plateau | sparse vegetation; wild sheep and goat, snow leopard, black-necked crane. |
| 2. Himalaya | Northwest, West, Central and East Himalayas | grass and evergreen tall trees, oak, chestnut, conifer, ash, pine, deodar; wild sheep, mountain goat, ibex, shrew, tapir, panda, snow leopard. |
| 3. Desert | Thar, Kutch | babul, kikar, wild palm; Indian bustard, camel, wild ass, fox, viper, rat snake. |
| 4. Semi-arid | Punjab plains, Gujarat, Rajputana | thom forest, thorny shrubs,.grasses and some bamboos, xerophytic herbs, jackal, ephemeral herbs; leopard, eagle, cobra, fox, buffalo. |
| 5. Western’Ghats | Malabar plains, Western Ghats | rice cultivation, areca nut and pepper, rubber,tea, coffee and forest tree plan-tations; caecilians (i.e., legless amphibians). |
| 6. Deccan Peninsula | Central highlands, Chota-Nagpur, Eastern highlands, Central Plateau, Deccan South | dry deciduous forests, cardamom, ginger, neem, fern; elephant, crocodile, monkey, jackal, heron, kingfisher. |
| 7. Gangetic plain | Upper and Lower Gangetic plains | moist deciduous forests,rice, wheat, teak, sal, shisham, mahua; tiger, elephant, gaur. |
| 8. Coast | West and East coast, Lakshaweep | mangrove, rice, coconut, rubber; crocodile, crab, shrimp, pelican, stork. |
| 9. North-East | Brahmaputra valley, Northeast hills | semi-ever green, evergreen forest, deciduous forest, orchids, bamboos, ferns, banana, mango, citrus and pepper; tiger, rhino leopard, turtle. |
| 10. Islands | Andaman and Nicobar | coral reefs and thick forests; wild pig, civet, dolphin, bat. |
Question 3.
Describe the threats of Biodiversity.
Answer:
Consequences of loss of Biodiversity :
Biodiversity is under serious threat. The International Union for the Conservation of Nature (IUCN) estimates that 22% of known mammals, 32% of amphibians, 14% of birds, and 32% of gymnosperms (plants that do not bear flowers or fruit, e.g. : ferns and moss) are threatened with extinction. Species that were abundant within the last 200 years have gone extinct. For example, passenger pigeons, which numbered more than three billion in the mid 1800s are now extinct. Animals like the polar bear, leopard, tiger, orangutan, otter and pangolin are shrinking in numbers.
Species extinction and loss of biodiversity can be as devastating for the earth as climate change and water pollution. Each species, no matter how small, may have an important role to play in the ecosystem. If there is a drastic increase or decrease in the population of a particular species, it can cause an imbalance in the ecosystem and have unforeseen, cascading effects that cannot be reversed. For instance, the loss of elephants in an area can cause the population of deer to multiply. As the number of deer increases, the available vegetation there decreases. Grass eating animals are affected adversely and may die. The cycle does not stop there. Carnivorous animals which feed on herbivores are, in turn, deprived of prey. Another example is the decline of the honey bee population which is adversely affecting the production of several crops, as pollination fails to take place in the absence of bees.
Causes of loss of Biodiversity / Threats to Biodiversity :
The primary cause of loss of biodiversity is habitat alteration caused by human activities which directly or indirectly affect the ecosystems. These dangers to biodiversity include: population growth and resource consumption, climate change and global warming, habitat conversion and urbanization, invasive alien species, over exploitation of natural resources and environmental degradation.
The table below summarizes the main threats to biodiversity in India
| Main Threat | Reasons |
| 1. Loss and destruction of natural habitats. | Urbanization, road expansion, industrilization, noise pollution etc. |
| 2. Reduction of Agricultural land. | Pollution, tolerence, distur-bances of natural habitat. |
| 3. Water, Air and Land pollution. | Use of heavy metals, pesticides, fertilizers etc. |
| 4. Entry of other species. | International trade and transport, growth of exotic breeds. |
| 5. Diseases and its effects on wild life. | Entry of exotic breeds, pollution, habitat destruction. |
| 6. Change of climatic conditions. | Deforestion, land conversion, carbon effluents. |
| 7. Drying of soil. | Extreme use of ground water. |
| 8. Entertainment and Amusement. | Misuse of natural habitats. |
Threats to Marine Water
| Main Threat | Reasons |
| 1. Destruction of species. | Industrialised fishing. |
| 2. Eutrophication. | Use of more fertilizers and pesticides. |
| 3. Soil erosion in coastal areas. | Collection of pebles, sand, beam travelling, dredging. |
| 4. Destruction of mangrooves, coral reefs, habitats of turtles. | Population explosion, sound pollution, tourism. |