Table of Contents
Biodiversity and its conservation
There are various types of organisms present around us. The predicted number of total species on this earth varies from 5 to 50 million and the average at 14 million, but only 1.7 million have been described till today and the distribution is highly uneven.
Concept of biodiversity OR What is biodiversity
Biodiversity is the variability among living organisms from all sources, including terrestrial, marine and other aquatic ecosystems and ecological complexes of which they are part; this includes diversity within species, between species, and if ecosystem.
The term ‘biodiversity’ refers to the totality of genes, species and ecosystems of a region. The biodiversity therefore includes different types of genes, different types of organisms, species and ecosystems of a given region.
There are three types of biodiversity:
1. Genetic diversity
2. Species diversity
3. Community and ecosystem diversity
1. Genetic diversity:
The number and nature of genes determine the character of the organisms. No two individuals have exactly the same genetic makeup. This difference amongst the genes of two different organisms is called genetic diversity.
2. Species diversity:
Species is a group of similar individuals, which are able to interbreed and produce fertile hybrids. All the members of a particular species have almost similar characters. But they differ markedly from the members of another species. The variation in the members of two different species in a region is called species diversity.
3. Community and ecosystem diversity:
Genetic and species diversity finally give rise to community and ecosystem diversity.
It has three perspectives:
1. Alpha diversity___________ diversity of organisms in the same community or habitat.
2. Beta diversity_____________ the inter community diversity
3. Gamma diversity________ diversity of habitats over the total landscape or geographical area
Uses of Biodiversity:
Biodiversity helps us in many ways; such as_
a. Ecosystem services:
- Biodiversity is essential for the maintenance of food chains and energy flow.
- It helps to maintain the gaseous composition of atmosphere and climate.
- It controls natural pests, protects soil and conserves and purifies water contents.
b. Source of food and improved varieties:
Biodiversity helps modern agriculture as a source material for breeding improved varieties, as a source of biodegradable pesticides.
c. Drug and medicines:
Biodiversity provides substances with therapeutic properties.
Ex_ Quinine, which is used to treat malaria is obtained from Cinchona ladgerina
Morphine, which is used as an analgesic, is obtained from papaver somniferum.
d. Aesthetic and cultural benefits:
Ecotourism, bird watching, wildlife, pet keeping, gardening, etc are some of the examples, Which show great aesthetic value of biodiversity.
Loss of biodiversity:
When people cut down trees, fill a wetland, plough grassland or burn a forest, the natural habitat of a species is changed or destroyed. This habitat loss is the primary cause of loss of biodiversity.
Natural disturbances and calamities, such as fire, tree fall, and defoliation by insects severely affect bio-communities. These can destroy Biodiversity on a very large basis.
The introduction of unwanted materials in ecosystems also severely affixes the living organisms. Eutrophication of water bodies drastically reduces Species diversity.
New species (exotic species), when entering a geographical region, have drastic effects on existing species (endemic species). These species may cause disappearance of existing Species through changed biotic interactions.
Extinction of species:
The disappearance of natural species is a natural process. But due to increasing human greed many species are on the verge of extinction, much before their normal natural extinction. This type of extinction is definitely a cause of worry.
There are three types of extinction processes.
1. Natural extinction: due to change in environmental conditions, the species, which are not fit to survive in the changed conditions, disappear from the earth.
2. Mass extinction: when a large group of organisms become extinct within a short span of time, the process is called mass extinction.
3. Anthropogenic extinction: when the cause of species extinction is human activities, it is called anthropogenic extinction. This type of extinction causes severe depletion of biodiversity.
Conservation of Biodiversity:
Biodiversity is very important for us for the proper balance of nature. Therefore it becomes necessary for us to protect our biodiversity. There are two basic strategies of biodiversity conservation, in situ (on site) conservation and ex situ( off site) conservation.
1. In situ conservation:
- The in situ conservation involves the protection of the total ecosystem (i.e, conservation of species in their natural environment).
- For this, several protected areas, biosphere reserves, sacred forests and lakes have been recognised, which include a group of typical ecosystems.
a. Protected Areas:
These are areas of lands and/or sea which are especially dedicated to the protection and maintenance of biodiversity, and natural and cultural resources. These are managed through legal or other effective means.
Ex: National Parks and Wildlife Sanctuaries
b. Biosphere Reserves:
Biosphere reserves are specialized protected areas, which represent natural biomes and contain unique biological communities.
c. Sacred Forests and Sacred Lakes:
These are the undisturbed areas, which are protected by tribal people due to some religious causes. Sacred forests are the most undisturbed forests, free from any human intervention.
2. Ex situ Conservation:
The ex situ Conservation includes the conservation of biodiversity in artificially developed areas such as botanical gardens, zoos or zoological parks and conservation stands.
a. Botanical Gardens:
These are the large, artificial made natural surroundings where a large number of plant species are kept. Botanical gardens are significant for their plant diversity.
b. Zoological parks:
Zoological parks and gardens are the protected and enclosed areas, which are developed to provide shelter to wild animals. Main object of creating the zoological parks is to create among people an interest and curiosity for animals.