· • largest assessment of the effect of humans on the earth’s ecosystems • found that over...

http://www.e-taxonomy.eu

Taxonomy Summer School1-15 September 2008

EDITPresentation title

Presenter’s positionPresenter’s name

EDIT Biodiversity

National Botanic Garden of Wales

Dr Natasha de Vere


What is biodiversity?

Biodiversity is the variety of life on earth

PopulationsIndividualsChromosomes

GenesNucleotides

Genetic diversity

Kingdoms

Phyla

Classes

Orders

FamiliesGeneraSpeciesSubspeciesPopulationsIndividuals

Organismal diversity

Biomes

BioregionsLandscapesEcosystemsHabitatsNiches

PopulationsEcological diversity


Definition of biodiversity

Large number of formal definitions; Delong (1996) reviewed 85!

“the variability among living organisms from all sources including, inter alia [among other things], terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems”.

Convention on Biological Diversity (CBD)


Measuring biodiversity

Biodiversity is a multidimensional concept that cannot be reduced to a single number

A

Which is most diverse?


Measuring biodiversity

Numbers Evenness Difference


Measuring biodiversity – species richness

Species richness is the most common measure of biodiversity.

This is because:

• Species often keep their genes to themselves.

• Easier to count (humans tend to recognise species)

• Humans can visualise variation in biodiversity as variation in species richness.

• Existing information e.g. museums and herbaria.

• Surrogate for other measures of biodiversity.


Australasian birds-of-paradise

Biological speciesconcept

40 – 42 species

Phylogenetic speciesconcept

90 species

Measuring biodiversity – species richness

Disadvantages in the use of species richness as a biodiversity measure.

• Depends on species concept used.• Need to remember it represents only one element of biodiversity.


Spatial scales, alpha, beta and gamma diversity

• Alpha diversity refers to diversity within a particular area, community or ecosystem and is typically measured as the number of species within that area.

• Beta diversity is the species diversity between areas and involves comparing the number of species that are unique to each area.

• Gamma diversity is a measure of the overall diversity across a region.


How many species are there?

13.5 million? (lowest estimate 3.5, highest 111.5)


“If all matter in the universe except the nematodes were swept away, our world would still be dimly recognisable, and if, as disembodied spirits, we could investigate it, we should find its mountains, hills, vales, rivers, lakes and oceans represented by a film of nematodes”.

The actual number of species of nematode has been estimated to be between 1 million to 100 million species, with a conservative estimate of 1019 free living nematode individuals.

Cobb (1914)

Abundance of species


Mapping biodiversity

• 90% reduction in the habitat in an area will result in the loss of approximately 50% of the species that live in that habitat.

• 99% reduction will lead to the extinction of 75% of the species.

Log S = log c + z log A

S is the number of species

A is the area

z and c are constants

In general as the size of an area increases so does the number of species


Mapping biodiversity - hotspots

• High numbers of endemic species, high habitat loss.• 34 hotspots, combined area: 2.3% of Earth’s surface.


Value of biodiversity

• Direct uses e.g. food, fibres and medicines.

• Indirect uses e.g. ecosystem services such as atmospheric regulation, nutrient cycling and pollination.

• Non-use values: • Option value (for future use or non-use). • Bequest value (in passing on a resource to future generations).• Existence value (value to people irrespective of use or non-use).• Intrinsic value (inherent worth, independent of that placed upon it by humans).



Relationship between biodiversity, ecosystem function and human well-being


• Many uses not included in economic accounts leading to biodiversity being under-valued.

• Traditional national accounts do not include measures of the depletion of resources such as mineral deposits, soil nutrients and ecosystem services.

• Depletion shows as positive gain in GDP without registering decline in assets.



How much biodiversity is required to maintain ecosystem function?

Eco-systemfunction

A B C

Species richnessSpecies richnessSpecies richness

A: Redundancy: there is a minimum number of species required to carry out ecosystem processes and beyond this species are equivalent and their loss of little significance.

B: Rivet-popping: the loss of a few species may have no apparent effect on ecosystem processes but beyond certain thresholds ecosystem services will fail.

C: Idiosyncrasy: species have complex and varied roles so changes in diversity will cause changes in ecosystem functioning where the direction and magnitude of change is unpredictable.


Loss of biodiversity


Millennium Ecosystem Assessment

• Largest assessment of the effect of humans on the Earth’s ecosystems

• Found that over the last 50 years, humans have changed ecosystems more rapidly and extensively that in any comparable period of time in human history and that this has resulted in a substantial and largely irreversible loss in the diversity of life on Earth.


Main causes of biodiversity loss


Habitat change


Climate change


Invasive species


Over-exploitation

Atlantic cod stocks off the east cost of Newfoundland


Pollution (especially nutrient loading)

Estimated total reactive nitrogen deposition from the atmosphere (wet and dry) in 1860, early 1990s, and projected for 2050 (milligrams of nitrogen per square metre per year), from MEA (2005).


Conserving biodiversity – what actions can be taken?

The Millennium Ecosystem Assessment lists a number of actions that have been at least partly successful in

reducing biodiversity loss and can be further strengthened in the future.

Protected areas Species protection

Ex situ conservation

In situ conservation

Markets for biodiversity

Ecosystem restoration

International agreements

Education

Research

Capacity building

Sustainableagriculture

Slow climate change

Slow nutrientloading

Integrate biodiversity in development

planning

Correct markets that fail to include

ecosystem services

Eliminate subsidies that damage ecosystem

services


Biodiversity and taxonomy

Article 7 of the CBD requires the parties to the Convention to: • Identify and monitor biological diversity, particularly those aspects important for conservation and sustainable use. • Monitor activity which could have significant adverse impacts on the conservation and sustainable use of biological diversity and to • Maintain and organise data derived from identification and monitoring activities.

COP 3 identified a "taxonomic impediment“ to the delivery of the CBD

The Global Taxonomy Initiative (GTI) was launched in order to try and reverse this impediment.


Biodiversity and taxonomy

Global Strategy for Plant Conservation (GSPC)

“A widely accessible working list of known plant species, as a step towards a complete world flora”.

Target 1

http://www.bgci.org/files/Worldwide/GSPC/globalstrategyeng.pdf


Over-coming the taxonomic impediment - DNA bar-coding

A DNA barcode is a short gene sequence taken from standardized portions of the genome, used to identify species.


Works with fragments

Works for alllife stages

Un-maskslook-alikes

Reducesambiguity

Expertise goes further

Democratizesaccess

Hand-heldlife bar-coder

New leaves on tree of life

Shows value of

collections

Encyclopaediaof life

Ten reasons for DNA bar-coding


DNA bar-coding process

Building the DNA bar-code library

• Well-identified specimen

• Tissue sub-sample

• DNA extraction, PCR amplification

• DNA sequencing

• Data submission

Using the DNA bar-code library

• Unidentified specimen

• Tissue, DNA, sequencing

• Comparison with reference


Case study: National Botanic Garden of Wales

“The National Botanic Garden of Wales exists to develop a viable world-class national botanic garden dedicated to

the research and conservation of biodiversity and its sustainable utilisation, to lifelong learning and to the

enjoyment of the visitor”


Rare Welsh Plants Project

Conserve some of the most threatened plant species in Wales by providing a firm scientific basis for their

conservation.


Welsh flora – DNA bar-coding project

http://www.museumwales.ac.uk/en/home/


Waun Las National Nature Reserve


Plant collections

• Welsh flora

• Mediterranean ecosystems

• Temperate woodland ecosystems

• Medicinal plants


Education and training

Presenter’s institution logo

[email protected]


[email protected]

· • largest assessment of the effect of humans on the earth’s ecosystems • found that over...

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