The Global Biodiversity Assessment
ROBIN PELLEW
In the mid-1970s, a mysterious disease started
devastating rice crops in Indonesia. The Green Revolution had encouraged
the introduction of new, high-yielding but genetically uniform varieties
of rice, highly vulnerable to attack by pathogens. Within a couple of
years the virus was threatening more than a million hectares, putting
hundreds of millions of people throughout Southeast Asia at risk.
The International Rice Research Institute (IRRI) rapidly screened all
6,273 varieties in its collections for resistance to the virus. Only one
possessed it - a low-yielding, spindly species, collected from the wild in
Southern India but thought to have no commercial value. The resulting new
variety, IR36, is now planted as yet another genetic monoculture over
millions of Asian hectares - vulnerable to the next pathogen whose natural
selection outpaces the plant breeders.
Will there still be an uncultivated wild variety of rice possessing the
genes needed to save people from starving when the next pathogen strikes?
Or will it already be extinct?
If climate change radically alters the patterns of agriculture throughout
the world, as inevitably it will, where will the genetic material come
from to produce the new crop varieties on which human survival will
depend? Gene banks, like the IRRI's, may provide a partial answer, but the
greatest gene bank of all is nature, and this is being destroyed at an
increasing rate.
This is the conclusion of the Global Biodiversity Assessment, the
most comprehensive analysis of the science underpinning biological
diversity ever undertaken. Funded by a $2 million grant from the Global
Environment Facility, it is the work of over 1,500 scientists from all
over the world coordinated by UNEP.
The Assessment finds that the Earth's biological resources are under
serious threat. Biodiversity - the myriad of genes, species and ecosystems
that collectively make up what we call Nature - may have taken 4 billion
years to evolve, but it seems destined to be largely destroyed in just
four human generations. Rates of species extinction are estimated to be 50
to 100 times the natural background rate: this could increase to 1,000 to
10,000 times with the forest loss projected for the next 25 years.
Unless direct action is taken now to protect biodiversity, we will lose
forever the opportunity of reaping its full potential benefit.
Our knowledge is fragmentary. Only some 1.75 million, or 13 per cent, of
the total number of species on Earth, estimated by the Assessment at
between 13 and 14 million, have even been scientifically described. We
know more about the stars than about the life-forms that cohabit our own
planet - a reflection, perhaps, of the disproportionate amount of research
funding spent on astronomy compared to biology.
Unlike the climate change and ozone treaties, the Convention on Biological
Diversity was not preceded by a comprehensive scientific assessment.
Scientists persuaded politicians and lawyers that biological resources
were being destroyed so fast that the future well-being of the human race
could be imperilled. This urgency drove the negotiations of the treaty,
but its implementation has floundered in political infighting over
conflicting priorities for budget allocations, largely because of the lack
of consensus on the science base. The purpose of the Assessment is to
provide the scientific foundations needed to develop effective policies
for conserving biodiversity and for benefiting from the use of its
resources.
Sections of the report cover the magnitude and distribution of biological
diversity; its maintenance and loss; inventory and monitoring; functional
properties and dynamics at the ecosystem level; economic and
non-consumptive values; human impacts; and conservation measures. A key
chapter looks at biodiversity's role in providing the raw materials for
biotechnology: many countries have a dominant interest in ensuring both
continued access to genetic resources and equitable sharing of the
benefits.
The Assessment concludes that the best way to save biodiversity is to
value it, whether as a resource for direct use on a sustainable basis, or
for its indirect functions, such as maintaining freshwater supplies or
providing a sink for greenhouse gases.
Biodiversity is the barometer of how well we are doing in sustainable
development. So long as we continue to lose it, our development is not
ecologically sustainable. And though there are signs of greater awareness,
we still have a long way to go.
Dr. Robin Pellew is Director, WWF-UK.
Global Biodiversity Assessment is published for UNEP by Cambridge
University Press, as a 1,140 page report (hardback $120/paperback $44.95)
and a 56 page Summary for Policy Matters ($14.95). The editorial team
comprised R. T. Watson (Chair), V. H. Heywood (Executive Editor), I.
Baste, B. Dias, R. Gamez, T. Janetos, W. Reid and R. Ruark.
Copies are available from Cambridge University Press or UNEP's
distributors, SMI (Distribution Services) Limited, PO Box 119, Stevenage,
Hertfordshire SG1 4TP, England.
