Feature

Biodiversity Spice of Life

Variety is not only the spice of life, it may well be a vital ingredient for a healthy planet.

By Colin O'Donnell

Biodiversity is a concept which has gained a great deal of attention in recent years. The controversial biodiversity treaty at the Rio Earth Summit saw nations arguing over the advantages and disadvantages of encouraging biodiversity, and numerous conferences have looked at the scientific and political problems involved.

The generally accepted aim of conservation biology seems to be the preservation and restoration of biological diversity.

The three most widely used approaches to achieving this goal are through reserve systems which sample the full range of biodiversity; through threatened species programmes; and, increasingly, through restoration programmes and the reconstruction of relatively stable and productive ecosystems.

Although conservation biology is seen as a new science, both it and the maintenance of biodiversity are not new concepts. We have been practising conservation biology in New Zealand for many years, under such umbrellas as reserve design, wildlife and plant management, and endangered species programmes.

However, by identifying conservation biology as a discipline of science, the people working in a broad spectrum of conservation research and management programmes have been given political and public focus, and a more effective network for information sharing.

It is now respectable, and indeed necessary, for scientists to broaden their advocacy roles by calling for the conservation of biological resources in political arenas. Too often in the past, scientists have aired their findings in scientific forums, forgetting, or relying on others, to translate that information for people to use. By identifying conservation biology as a valid scientific pursuit, a responsibility is being engendered for scientists to be far more effective communicators and educators in the wider community.

Biodiversity is becoming one of the catch-phrases of conservation biology, not only because the maintenance of biodiversity makes strong biological and social sense, but because it has strong political appeal.

What is biological diversity? Put simply, it is the amount of variety of life -- and our future depends on it. The preservation of biodiversity not only includes maintaining as many species as possible, but also maintaining the full range of genetic variation present in those species and the range of ecosystems they form.

Biodiversity is not a fixed entity. It is a constantly changing pool, which is increased by new genetic variation and reduced by extinction and habitat degradation. Conserving biodiversity is becoming a major task, particularly in more fertile areas, heavily disturbed areas and urban environments.

Groups such as invertebrates, non-vascular plants, micro-organisms and fungi in particular are poorly known, and their conservation causes many problems. For these groups, which include many species not yet discovered -- let alone described by science -- it will be essential to identify and protect species assemblages characteristic of different ecosystems rather than described single species.

There are ethical and practical reasons for conserving biological diversity. Ethically, all species have a right to exist. Practically, the quality of human life depends on food, medicines and industrial products coming directly from nature. This is especially relevant for centres of diversity such as tropical forests, which are so under threat today.

We depend on ecosystem processes, for example, to maintain water quality, soil productivity, recycling and energy. We depend on knowledge of species and their interrelationships to maintain agriculture, forestry and horticultural practices. The loss of biological diversity is occurring at an alarming rate, with as many as 10,000 species, and many more distinctive populations, becoming extinct each year. This irreversible change is occurring much more rapidly than changes in our global climate.

New Zealand has a unique range of animal and plant species, many of which are ancient in origin. The Department of Conservation is developing a biodiversity policy for conservation management planning in New Zealand. It will build on the progress already made, and provide a philosophical framework for much conservation activity in the future. It will also acknowledge the contribution New Zealand can make towards global protection of biodiversity.

A discussion document, Protection and Conservation of New Zealand's Natural Biodiversity, is being prepared by DOC, and will be circulated for wider comment in the future.

Colin O'Donnell is in DOC's Science and Research Division.