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Why Is Biodiversity Important? Who Cares?
Author And Page Information
by Anup Shah
This Page Last Updated Wednesday, November 18, 2009
This page:http://www.globalissues.org/article/170/why-is-biodiversity-important-
who-cares.
To print all information e.g. expanded side notes, shows alternative links, use the
print version:
http://www.globalissues.org/print/article/170
At least 40 per cent of the world’s economy and 80 per cent of the needs of the poor
are derived from biological resources. In addition, the richer the diversity of life, the
greater the opportunity for medical discoveries, economic development, and adaptive
responses to such new challenges as climate change.
— The Convention about Life on Earth, Convention on Biodiversity web site.
This web page has the following sub-sections:1. Why Is Biodiversity Important?2. A Healthy Biodiversity Offers Many Natural Services3. Species Depend On Each Other1. Soil, Bacteria, Plants; The Nitrogen Cycle2. Bees: Crucial Agricultural Workers3. Interdependent Marine Ecosystem4. Interdependency Vs Human Intervention4. Biodiversity Providing Lessons For Scientists In Engineering5. More Important Than Human Use Or Biological Interest6. Putting An Economic Value On Biodiversity7. More Information
Why Is Biodiversity Important?
Biodiversity boosts ecosystem productivity where each species, no matter how
small, all have an important role to play.
For example,
A larger number of plant species means a greater variety of crops
Greater species diversity ensures natural sustainability for all life forms
Healthy ecosystems can better withstand and recover from a variety of disasters.
And so, while we dominate this planet, we still need to preserve the diversity in wildlife.Back to top
A Healthy Biodiversity Offers Many Natural Services
Ecosystems such as the Amazon rainforest are rich in diversity. Deforestation threatens
many species such as the giant leaf frog, shown here.(Images source: Wikipedia)
A healthy biodiversity provides a number of natural services for everyone:
Ecosystem services, such as
Protection of water resources
Soils formation and protection
Nutrient storage and recycling
Pollution breakdown and absorption
Contribution to climate stability
Maintenance of ecosystems
Recovery from unpredictable events
Biological resources, such as
Food
Medicinal resources and pharmaceutical drugs
Wood products
Ornamental plants
Breeding stocks, population reservoirs
Future resources
Diversity in genes, species and ecosystems
Social benefits, such as
Research, education and monitoring
Recreation and tourism
Cultural values
That is quite a lot of services we get for free!
The cost of replacing these (if possible) would be extremely expensive. It therefore
makes economic and development sense to move towards sustainability.
A report from Nature magazine also explains that genetic diversity helps to prevent the
chances of extinction in the wild (and claims to have shown proof of this).
To prevent the well known and well documented problems of genetic defects caused by
in-breeding, species need a variety of genes to ensure successful survival.
Without this, the chances of extinction increases.
And as we start destroying, reducing and isolating habitats, the chances for interaction
from species with a large gene pool decreases. Side Note»»Back to top
Species Depend On Each Other
While there might be “survival of the fittest” within a given species, each species
depends on the services provided by other species to ensure survival. It is a type of
cooperation based on mutual survival and is often what a “balanced ecosystem” refers
to.
Soil, Bacteria, Plants; The Nitrogen Cycle
The relationship between soil, plants, bacteria and other life is also referred to as the
nitrogen cycle:
(Image source: Wikipedia)
As an example, consider all the species of animals and organisms involved in a simple
field used in agriculture. As summarized from Vandana Shiva, Stolen Harvest (South End
Press, 2000), pp 61–62:
Crop byproducts feed cattle
Cattle waste feeds the soil that nourish the crops
Crops, as well as yielding grain also yield straw
Straw provides organic matter and fodder
Crops are therefore food sources for humans and animals
Soil organisms also benefit from crops
Bacteria feed on the cellulose fibers of straw that farmers return to the soil
Amoebas feed on bacteria making lignite fibers available for uptake by plants
Algae provide organic matter and serve as natural nitrogen fixers
Rodents that bore under the fields aerate the soil and improve its water-
holding capacity
Spiders, centipedes and insects grind organic matter from the surface soil and
leave behind enriched droppings.
Earthworms contribute to soil fertility
They provide aerage, drainage and maintain soil structure.
According to Charles Darwin, “It may be doubted whether there are
many other animals which have played so important a part in the history
of creatures.”
The earthworm is like a natural tractor, fertilizer factory and dam,
combined!
Industrial-farming techniques would deprive these diverse species of food sources
and instead assault them with chemicals, destroying the rich biodiversity in the soil
and with it the basis for the renewal of the soil fertility.
Shiva, a prominent Indian scientist and activist goes on to detail the costs associated
with destroying this natural diversity and traditional farming techniques which recognize
this, and replacing this with industrial processes which go against the nature of diversity
sustainability.
Bees: Crucial Agricultural Workers
Bees are crucial for agriculture. (Images source: Wikipedia)
Bees provide enormous benefits for humankind as another example.
As reported by CNN (May 5, 2000), “One third of all our food—fruits and vegetables—
would not exist without pollinators visiting flowers. But honeybees, the primary species
that fertilizes food-producing plants, have suffered dramatic declines in recent years,
mostly from afflictions introduced by humans.”
As German bee expert Professor Joergen Tautz from Wurzburg University adds:
Bees are vital to bio diversity. There are 130,000 plants for example for which bees are
essential to pollination, from melons to pumpkins, raspberries and all kind of fruit trees
— as well as animal fodder — like clover.
Bees are more important than poultry in terms of human nutrition.
— Joergen Tautz interviewed by Michael Leidig, Honey bees in US facing extinction, The
Telegraph, March 14, 2007
Researchers are finding reasons for the massive decline hard to pinpoint, but suspect a
combination of various diseases, environmental pollution, environmental degradation
(leading to less diversity for bees to feed from, for example) and farming practices
(such as pesticides, large monoculture cropping, etc).
The link and dependency between plants, bees, and human agriculture is so crucial, the
two scientists writing up years of research into the problem summarized with this
warning:
Humankind needs to act quickly to ensure that the ancient pact between flowers and
pollinators stays intact, to safeguard our food supply and to protect our environment for
generations to come. These efforts will ensure that bees continue to provide pollination
and that our diets remain rich in the fruits and vegetables we now take for granted.
— Diana Cox-Foster and Dennis van Engelsdorp, Solving the Mystery of the Vanishing
Bees, Scientific American, April 2009
Interdependent Marine Ecosystem
Whaling is often controversial. (Image source: © Greenpeace)
An example from the seas (originally mentioned here years ago but removed because
the link to the story no longer worked), was described byNational Geographic Wild in a
program called, A Life Among Whales (broadcast June 14, 2008).
It noted how a few decades ago, some fishermen campaigned for killing whales because
they were threatening the fish supply and thus jobs.
A chain of events eventually came full circle and led to a loss of jobs:
The massive reduction in the local whale population meant killer whales in the
region (usually preying on younger whales) moved to other animals such as seals;
As seal numbers declined, the killer whales targeted otters;
As otter numbers were decimated, the urchins and other targets of otters
flourished;
These decimated the kelp forests where many fish larvae grew in relative
protection;
The exposed fish larvae were easy pickings for a variety of sea life;
Fishermen’s livelihoods were destroyed.
Interdependency Vs Human Intervention
But nature can often be surprisingly resilient, often without the need for human
interventions. For example, a documentary aired on the BBC (I unfortunately forget the
name and date, but in the 1990s) described two national parks in Africa where elephant
populations had grown quite large within those artificial boundaries. The usual way to
deal with this was to cull the population to try and keep the ecosystem in balance.
Without this, elephants were stripping vegetation bare, affecting other animals, too.
(Image source: Wikipedia)
A scientist pleaded with park management not to cull and let nature take its course.
Being against prevailing thought, they would not agree. In the end they agreed to let
one park have its elephants culled, while the other would be left alone.
A few years later, they found the park with the culled population had remained in poor
condition. The park where things were left alone has naturally regenerated; the large
elephant populations eventually reduced in number as they undermined their own
resource base. The natural pace at which this happened allowed vegetation to grow
back. Other wildlife grew in numbers and the ecosystem was generally back in balance.
Back to top
Biodiversity Providing Lessons For Scientists In Engineering
For a number of years now, scientists have been looking more and more at nature to
see how various species work, produce, consume resources, trying to mimic the
amazing feats that millions of years of evolution has produced.
As just one small example, some spiders can produce their silk with a higher tensile
strength than many alloys of steel even though it is made of proteins. So biologists are
looking at these processes in more depth to see if they can reproduce or enhance such
capabilities.Back to top