The materials or substances occurring in nature that exist without the actions of humankind are known as natural resources. The conservation of natural resources is important for the preservation of natural, biological diversity.

International Union for Conservation of Nature (IUCN) was founded on 5 October 1948 in France by Julian Huxley. It is working in the field of conservation of nature and sustainable use of natural resources.

Those species whose number of individuals is greatly reduced to a critical level and are at a high risk of extinction in the wild are known as endangered species. Some examples of endangered species are Brown spider monkey, Bengal tiger, Ganga river dolphin, Indian Rhino, Black buck, etc.

A total of 34 hotspots in the world has been identified till date by Norman Myers.

When a graph is drawn to compare the relationship between species richness and area for wide variety of texa, the graph appears to be a rectangular hyperbola.

• The species of plants contribute to the traditional medicines used by native peoples around the world are approximately 25,000.
• Some examples of traditional plants used for medicinal purposes are ginger, garlic, chamomile, tulsi, etc.

• Almost 25 percent of plant species are used for the production of the drugs currently sold in the market worldwide.
• Some plants used for the production of drugs are camphor tree, coca plant, poppy, turmeric, etc.

The extent to which numbers of different species are equal or skewed well refer to species eveness or relative abundance. Species eveness or relative abundance depends upon availability of natural resources essential for organisms.

Cryopreservation is the method of preserving living organisms or their parts at extremely low temperature. To preserve seeds that rapidly lose viability and cannot survive desiccation are preserved by this method.

The impacts of introducing a non-native or  invasive species  to an  ecosystem  will vary depending on a number of factors.

In some instances, the introduced species may not survive. If there is no  ecological niche  for the species to fill or the species cannot adapt to fill a different ecological  niche, the species will likely go extinct relatively quickly at the local level.

However, if the species is a generalist, or a species able to thrive in a variety of environments and consume many food sources, that species will likely do well. If the ecosystem has reached its stable state, this means that the  invasive species  will have to replace a native species. No two species can share the same ecological niche, thus one will be better adapted and survive. If the invasive species is better adapted, it will out compete the native species.

If the species reproduces quickly, it is also more likely to thrive in a new ecosystem. If it can reproduce and grow faster than its competitor, it will eventually out compete that species.

Typically, invasive species harm an ecosystem. For example, the Burmese python is found in the US but it isn 't supposed to be here. These snakes were likely released by humans and were pets at one time. The environment is suitable for them and they have adapted to the area.

Introducing a new species can also introduce any diseases that species has. These new diseases can spread to other native species and negatively affect them.

Introducing exotic species into new areas will increase competition for food and space. Sometimes, exotic species brings disease along with them. Exotic species in new area do not lead to extinction of native species.

More than 15,500 species worldwide is facing threat of extinction which includes amphibians, gymnosperms, reptiles, birds and mammals etc.

• The Amazon rainforest is the world ’s largest tropical rainforest and is also known as the Amazon Jungle or Amazonia.
• Approximately 20 percent of the total oxygen in the Earth ’s atmosphere is released by the Amazon forest by the process of photosynthesis.

The materials or substances occurring in nature that exist without the actions of humankind are known as natural resources. These resources can be conserved by using them wisely.

The organisms that has been completely eliminated or died out from earth are called extinct organisms. For example Dodo.

Amzonian rain forests are called as lungs of forest because it contains different kinds of vegetation that purify the atmosphere of the earth.