Issues relating to biodiversity Flashcards
What is biodiversity?
All biotic beings!
The variability among living organisms from all sources including terrestrial, aquatic and marine eocystems.
the global stocks of biological diversity generate a flow of services to all societies on earth.’
What are the three components of biodiversity that have a hierarchal and niche overlap?
Ecological diversity – Biomes, bioregions, Landscapes, Ecosystems, Habitats, Populations
Taxonomic diversity – Kingdoms, Phyla, Famililes, Genera, Species, Sub species, Populations, Individuals
Genetic diversity – Populations, Individuals, Chromosomes, Genes, Nucleotides
How is biodiversity measured?
Biodiversity cannot be measured precisely, however species richness can be used (number of species in a given area).
What is the problem measuring biodiversity with species richness?
- What constitutes a species is not well defined.
- Species that are taxonomically similar may be ecologically different
- Species vary in abundance within communities, with few being dominant
- Counting species does not take into consideration how varied each species is, for example, genes provide the adaptive variability for resilience to environmental change, and different populations retain different adaptation.
How many species are there in the world?
It is estimated that there are between 7 and 30 million different species on the earth, but there may be up to 100 million. However, the current best estimate ranges from 12.5-14 Million species.
How many species have been scientifically described?
1.75 – 2 Million species
What is the pattern of gradients in species richness is there
Species richness decreases polewards from the tropics
Why should biodiversity be conserved?
Biodiversity is under threat from anthropogenic driven changes such as habitat loss and climate change. In addition to this, biodiversity provides humans with significant benefits, such as food and clean water from ecosystem services.
What are the reasons biodiversity should be conserved?
Moral and ethic responsibility Aesthetics Ecosystem services Knowledge Living beings are intrinsic in nature (end in themselves).
What would happen if we lost biodiversity?
Crisis. Loss of food, building materials, recreation. Basically the loss of ecosystem services which contribute to human well-being.
What are the specific concerns for biodiversity?
Population growth and increasing rates of consumption
Key concerns;
Half of the habitable planet has already been disturbed, at least partially by humans
Verge of mass extinction of species
Rapidly accelerating losses of species and habitats
Incomplete knowledge of ecosystems and the diversity within them
How rapid is the accelerating loss of species?
Over the last 200 years it is estimated that human actions have raised the current rate of extinction of mammals by 40 times that of the expected rate.
How bad is the loss of species situation in Europe?
64 endemic species are now extinct
38% of bird species are under threat
45% of butterfly species are under threat
5% of sea and land molluscs are under threat
Where have the highest rates of extinction been?
On Islands, mainly due to being endemic species.
What socio-economic factors have been linked to losses in biodiversity?
Demographic change
Poverty and equality
Policies, markets and politics
Social change and development
