How Do I Understand Biodiversity?

How Do I Understand Biodiversity?

India covers about 2 per cent of the land area of the world but possesses more than 8 percent of world’s biodiversity. This biodiversity is not evenly distributed in India. It is more concentrated in Western Ghats & in the north- eastern states such as Arunachal Pradesh & Assam. These areas are therefore, called “Biodiversity Hotspots.” Andaman & Nicobar Islands also have remarkable biodiversity.

Indian biodiversity is characterized by high endemism. It means a number of species have limited ranges, being confined to particular areas only & not found anywhere else in the world. Such species obviously have high conservation value, should receive highest priority in any conservation programme as their loss implies that the world heritage becomes so much the poorer.

But why should we care to protect and conserve biodiversity, many people would ask. The simplest answer to this question is this: the variety of species provides a gigantic gene bank which becomes an unlimited source of food & fibre, medicines, antibiotics & pesticides and raw materials for different industries, small & large scale. Wild genes are much stronger in resisting diseases & can impart this strength to domesticated plants such as crops to make them pest resistant. Forest food is an important supplement in the diet of many communities in India. Wild plants can also be an additional source of energy as Pongamia ( Karanj ) and Jetropha have shown.

If biodiversity is so useful, how do we account for it? Do we know how many plants and animals are immediately useful to human beings, how many are likely to be useful in future and how many are not directly useful? To account for each & every species of plants from lichens to trees and of animals from bacteria to larger animals like whales and elephants, is a mind-boggling task. No nation has achieved this feat so far. We have initiated an effort to document biodiversity as much as possible by preparing biodiversity registers for the countryside & for urban areas. But it is feared that a lot of biodiversity is going to be lost by the time we complete this task!

Why is this so? For biodiversity is not only the number & variety of species & sub- species of plants & animals, higher & lower, but also includes the variety of habitats & niches available in a particular area. Habitat is the address & niche is the profession of each species. It is extremely difficult to separate out & count each & every habitat & niche as they are connected to each other & to larger divisions like biomes in a maze of linkages. Our ecological knowledge is not adequate to understand all these linkages. In our precipitate haste to industrialize & urbanize, we may be unintentionally destroying a number of habitats & niches. The collapse of linkages must be having a devastating impact on biodiversity!

This way we are destroying forever not only the gene bank but also the verybasis of ecological knowledge & understanding.

The reasoning so far makes clear that biodiversity knowledge is not enumeration of species & sub species only. We must also try to understand what habitats & niches species & sub- species represent? The wonderful diversity of attractive flowers that adorns many a lateritic plateau & open area in Western Ghats, during monsoons, is a case in point. These areas are “open” because of unrestricted grazing & trampling by our domestic animals & cutting of wood by human beings. The character of biodiversity on these plateaus when they were not “open” must be quite different from what it is today. If we enclose this area & protect it from grazing & cutting, the present diversity of attractive flowers is likely to be replaced by some other set of plants. Which is important for us? The attractive flowers which is an expression of nature’s reaction to a variety of impacts? Or the more sedate variety of plants which emerges when these impacts are
removed?

Cast in this mould, the question of biodiversity enumeration & conservation appears to be quite an intricate one. We must understand that biodiversity is nothing but an expression of certain physical conditions. In a country like India, which boasts of human settlements dating back to thousands of years, human beings have been constantly modifying these conditions. Biodiversity must have been modifying too. In the name of preserving certain apparently “natural” areas, we have evolved a system of protected areas like sanctuaries & national parks. Yet they are not completely immune from human interference. It means that the biodiversity that these areas manifest must have been modified over the years. A study in Germany has shown that 65 % of biodiversity is found outside protected areas. It is likely that this biodiversity is the result of human modification of habitats & in a sense “man- made diversity, while the 35 % which remains within protected areas are an expression of physical conditions which existed some years ago.

The significance of biodiversity then seems to depend on decisions made by human beings in a particular country or nation. People must decide how much area they would continue to modify & how much they would leave to relapse into physical conditions that existed in the past. As such biodiversity is quite a dynamic concept. Enumeration of biodiversity cannot be once for all. Each time we enumerate or document we must put a date on it. We should repeat this exercise every 5 or 10 years. In fact we should have a census of biodiversity every 5 or 10 years, as we census human beings. If we can describe & quantify physical conditions of the area, each time we enumerate, we may begin understanding the linkages between biodiversity & physical conditions. An NGO from Pune enumerated the biodiversity of Metropolitan Area at the turn of century. In some cases as in birds, they were able to establish the change in the character of biodiversity as some older records were available. If they repeat the exercise, and also record modifications in physical conditions, linkages between these two can be established with much more certainty. Indeed if somehow the scale of human impact can be quantified, the character of biodiversity can be related to the scale of human impact. This is directly useful in restoration & conservation of biodiversity.

Together with physical conditions, biodiversity also helps to define the character of nature’s services. If in an area atmosphere, soil and water are polluted, nature’s services such as providing atmospheric balance, soil formation & self- cleansing ability of flowing water, will be affected. The existing biodiversity will be an indicator of such disturbed conditions. The linkage between the degree of disturbance & the character of biodiversity can thus be established.

If the restored area is monitored annually we will understand how physical conditions & biodiversity begin to “relapse” to conditions that existed before they were modified by human beings.

Some people have differentiated between the “natural” & “domesticated” biodiversity. In the above sense, it is extremely difficult to locate & define natural & pristine biodiversity. The better differentiation would be between biodiversity that is only indirectly useful to human beings and has more or less intrinsic value and biodiversity which is directly useful & is associated with them.

How then do I understand biodiversity? I feel biodiversity is one of the components of Nature. If we single it out, accord it greater value, try to glorify it, we obtain a distorted view of nature. Biodiversity should be cast in its proper perspective: the time scale, physical conditions & most important, the character & intensity of human impact.

If conservation of biodiversity through protection & elimination of human impact, is planned, one must accept that it will mean a kind of relapse into conditions that existed sometime in the past. If biodiversity is to be taken care of in a human milieu, we must minimize human impact in certain natural processes such as the drainage pattern, the balance of erosion & deposition and stepping stones & corridors for the movement of life forms.

Prakash Gole