The Concept of Biodiversity
We have an immense range of forests, wetlands, grasslands, deserts, freshwater bodies, marine areas, coral reefs, hills and mountains in our world. Various organisms like plants, animals and microorganisms inhabit all these areas.
An association of all the plants at a particular place is called a Plant Community and the association of all the animals at the same place is called an Animal Community. Both the plant and animal communities inhabit a particular place living completely merged and interacting among them. Members of a community not only interact with the members of other communities, they interact with the members of their community and with the physical environment around them, as well.
The physical environment surrounding a community is called as its habitat. Thus, a habitat is the place or area where communities live.
The association of all the communities of plants, animals and microorganisms at a particular place is called as biota or the Biotic Community.
In a biotic community we may observe some species of plants and animals or microorganisms in abundance or in scarcity. Vast variability exists in the distribution or occurrence of different life forms in different habitats. The variability of life forms in a particular habitat is considered as the biodiversity of that habitat.
The biodiversity of an area is important for running the processes of nature in that area. If the biodiversity of an area is depleted or disturbed for some reason, the processes of nature may not run properly in that area. It will lead to a condition which is called as Natural Imbalance. This natural imbalance causes further damage to nature and its biodiversity. So, the balance of nature must be maintained at all costs.
Since humans and also all the other organisms of the natural environment derive their livelihood and all the other things from nature, it may be a suicidal tendency if someone disturbs this balance and causes any damage to the biodiversity. Here, we are going to study about the real concept of biodiversity, its benefits and values, and its various types demarcated by ecologists.
Definitions of Biodiversity
Biodiversity is a composite word made from two words- Biological and Diversity. This word was used for the first time by the Science of Conservation in the year 1975 as Natural Diversity. The word biodiversity is supposed to have been coined by W. G. Rosen in 1985 while he was planning for the National Forum on Biological Diversity held in 1986. The word biodiversity appeared first in a publication in 1988 when entomologist C. O. Wilson used it as a title of the proceedings of that forum.
According to a report of the United Nations Environmental Programme -2002(UNEP-200), biodiversity refers to the variability among living organisms from all sources including terrestrial, marine and other ecosystems, and the ecological complexes of which they are parts. This includes diversity within species, between species and, within and between ecosystems.
The same opinions regarding biodiversity were also expressed in the United Nations Earth Summit in 1992 which was organized in Rio de Janeiro. The Ministry of Environment and Forests, Government of India reported in 1998 that biodiversity is the species richness of plants, animals and microorganisms, including their genetic make-up and the communities they form.
According to another opinion, -the varieties of life forms, their variations and abundance with the variation of the components of their habitat is called as biodiversity or biological diversity.
Further, some ecologists say that Biodiversity is the sum of all the different species of plants, animals, fungi and other microorganisms living in the environment and the variety of habitats where they live. In a nutshell, the range of organisms, present in a given ecological community or system is called as biodiversity.
The ecologists of the world also accept another definition of biodiversity according to which- “The totality of genes, species, and ecosystems of a region is called as biodiversity.” This definition presents a unified view of the traditionally accepted three levels of the identification of biodiversity, – the genetic diversity, the species diversity, and the ecosystem diversity.
Values of Biodiversity
The word ‘Value’ has different meanings. In Mathematics, value is the amount represented by a letter or symbol. For example, we write that the value of π (Pie) is 3.14 or 22/7. In regular practice, by value, we mean the amount of money or other goods for which something can be exchanged. In religion and culture, we mean value, the belief about what is right or wrong and what is important in life. We refer to cultural, religious, moral and social values. Truth and non-violence are universal values of life. Here in the present case, by value we mean the quality of being useful or important.
Biodiversity has great qualities of being useful to man and also to the environment. Our ancestors realized the importance of the existence and well-being of all the life forms along with the physical components of nature constituting their habitats. They realized the importance of forces in nature and experienced their impacts on life. That’s why they prayed for the maintenance, regulation and well-being of the diversity of life on this earth to which they regarded as ‘mother’.
In the same spirit we celebrate the “Earth Day” on 22nd April every year across the world. The year 2006 was celebrated as the Year of Biodiversity in India. The earth has an amazing biodiversity interwoven with each other. We celebrate the earth day to take care of the mother earth and all of its life forms. Thus, the value of biodiversity is interwoven in all the religions and cultures across the world
Loss of Biodiversity
Loss of biodiversity relates to any type of tragedy, danger, death or reduction that is caused due to anthropogenic pressures in populations of species of plants and animals inhabiting different segments of the biosphere.
The loss of biodiversity has been a natural process since time immemorial. Several episodes of multiple losses of species have occurred in the history when large populations of animals and plants died off.
Naturalists call these episodes as Mass Extinction. Most of the scientists agree that life on earth is now faced with the most severe extinction episode since the event that drove away the dinosaurs to extinction. Nobody knows exactly how many species are being lost because no one knows exactly how many species exist on the earth.
Estimates vary. However, the most widely accepted figures lie between 10 and 13 million species. Of these, as many as 27000 species are becoming extinct each year. It means at least 3 species are going extinct every year. Here are some examples of the actual loss of species across the world-
About 816 species are known to have gone extinct in the wild over the past 500 years due to anthropogenic activities. Some 2,000 species of Pacific Island Birds have gone extinct since the colonization of human species. Varieties of basic sources of food such as wheat, corn, apples, potatoes, etc. have gone extinct during the last 15 years. It is reported that about 1500 indigenous varieties of rice have become extinct during the last 15 years in Indonesia.
Causes of loss of Biodiversity
The loss or degeneration of Biodiversity worldwide is not a sudden process. Rather it took decades that too mainly due to growth of human population and exploitation by human beings. In a nutshell, some of the major causes of the degeneration of biodiversity are listed below. –
1. Growth of human population and activities of exploitation, overuse and misuse of resources by human beings.
2. Unsustainable pattern of consumption of resources of nature.
3. Increasing production of wastes and pollutants followed by different types of hazards in air, water and on land.
4. Development of urban areas, deforestation, mining activities etc.
5. International conflict.
6. Continuing inequalities in the distribution of wealth and resources.
7. Loss of habitats, habitat destruction and habitat fragmentation.
8. Decline and loss of species due to various reasons like illegal trade, poaching of animals, smuggling of wood, natural calamities, overuse etc.
9. Climate change and global warming.
10. Deposition of Nitrogen in the soil due to increasing use of nitrogenous fertilizers in agriculture.
11. Oil spills on sea surface cause death of various bird and fish species.
12. Introduction of invasive species.
