Biodiversity
22nd May
World Biodiversity Day
What is Biodiversity?
The variety of life on Earth, its biological diversity is commonly referred to as biodiversity.
The number of species of plants, animals, and microorganisms, the enormous diversity of genes in these species, the different ecosystems on the planet, such as deserts, rainforests and coral reefs are all part of a biologically diverse Earth.Appropriate conservation and sustainable development strategies attempt to recognize this as being integral to any approach to preserving biodiversity. Almost all cultures have their roots in our biological diversity in some way or form.
Declining biodiversity is therefore a concern for many reasons.
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.
A healthy biodiversity offers many natural services
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
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.
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:
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.
Bees: crucial agricultural workers
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
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
An example from the seas (originally mentioned here years ago but removed because the link to the story no longer worked), was described by National 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.
Large carnivores essential for healthy ecosystems
Three quarters of the world’s big carnivores are in decline. A study in the journal Science, notes that these large animals — such as lions, leopards, wolves and bears — are in decline, due to declining habitats and persecution by humans..This also has a negative impact on the environment, perhaps partly formed by outdated-views that predators are harmful for other wildlife. As the study notes, human actions cannot fully replace the role of large carnivores because these large carnivores are an intrinsic part of an ecosystem’s biodiversity.
As a simple example, the loss of a large carnivore may mean in the short term the herbivores they prey on may increase in numbers but this can also result in a deterioration of the environment as the herbivores can graze more, largely unchecked. Human intervention to perform the same services would be more costly.
Interdependency vs Human Intervention
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.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.
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.
More important than human use or biological interest
Many people may support environmental causes to help preserve the “beauty” of Nature. However, that is in a strange way, not really a justifiable excuse as it is a subjective, human or anthropomorphasized view.For many decades, various environmentalists, biologists and other scientists, have viewed the entire earth as a massive living organism or system due to the interdependent nature of all species within it. Some cultures have recognized this kind of inter-relationship for a very long time. Some have termed this Gaia.
While there are disagreements and differences on how this works, it suggests that ecological balance and biodiversity are crucial for all of earth, not just humans.
Putting an economic value on biodiversity
It was noted earlier that ecosystems provide many services to us, for free.Although some dislike the thought of trying to put an economic value on biodiversity (some things are just priceless), there have been attempts to do so in order for people to understand the magnitude of the issue: how important the environment is to humanity and what costs and benefits there can be in doing (or not doing) something.
The Economics of Ecosystems and Biodiversity (TEEB) is an organization — backed by the UN and various European governments — attempting to compile, build and make a compelling economics case for the conservation of ecosystems and biodiversity.
In a recent report, The Economics of Ecosystems and Biodiversity for National and International Policy Makers 2009, TEEB provided the following example of sectors dependent on genetic resources:
| Sector | Size of Market | Comment |
|---|---|---|
The Economics of Ecosystems and Biodiversity for National and International Policy Makers 2009  , p.17
| ||
| Pharmaceutical | US$ 640 bn. (2006) | 25-50% derived from genetic resources |
| Biotechnology | US$ 70 bn. (2006) from public companies alone | Many products derived from genetic resources (enzymes, microorganisms) |
| Agricultural seeds | US$ 30 bn. (2006) | All derived from genetic resources |
| Personal care, Botanical and food & Beverage industries | US$ 22 bn. (2006) for herbal supplements
US$ 12 bn. (2006) for personal care US$ 31 bn. (2006) for food products | Some products derived from genetic resources. represents ‘natural’ component of the market. |
- Halve deforestation by 2030, and
- Cut emissions by 1.5 Gt of CO2 per year.
- It would cost from US$ 17.2 – 33 billion per year
- The estimated benefit in reduced climate change is US$ 3.2 trillion
- The above would be a good return on the initial investment. By contrast, waiting 10 more years could reduce the net benefit of halving deforestation by US$ 500 billion.
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