(ESS) Topic 3: Biodiversity and conservation

- An introduction to biodiversity - Origins of biodiversity - Threats to biodiversity - Conservation of biodiversity

biodiversity

the total diversity of living systems

→ arises from evolutionary processes

• includes:

  • species diversity

  • habitat diversity

  • genetic diversity

species diversity

the number of species (richness) and their relative proportions (evenness)

habitat diversity

the range of different habitats in an ecosystem or biome

genetic diversity

the range of genetic material present in a population of a species

(caused by random mutations)

qualification of biodiversity

… is important to conservation efforts so that areas of high biodiversity may be identified, explored, and appropriate conservation put in place where possible

impact of human activity

the ability to assess changes to biodiversity in a community over time is important for assessing the …

natural selection

1. Within a population of one species, there is genetic diversity, which is called variation.

2. Due to natural variation, some individuals will be fitter than others.

3. Fitter individuals have an advantage and will reproduce more successfully than less fit individuals.

4. The offspring of fitter individuals may inherit the genes that give that advantage.

→ contributes to the evolution of biodiversity over time

1. geographic

2. behavioural

3. genetic

3 types of isolation → factors affecting natural selection

speciation

the formation of new species when populations of a species become isolated and evolve differently from other populations

causes of isolation of populations

• climatic change

• plate movements

• mountain formation

• changes in rivers

• sea level change

causes of mass extinction

• tectonic plate movements

• super-volcanic eruption

• climatic changes (including drought and ice ages)

• meteorite impact

mass extinction

cause new directions in evolution and therefore increased biodiversity

movement of tectonic plantes

• … results in the formation of mountains, islands, and ocean basins, which act as barriers and corridors for the dispersal of species

  • leads to isolated populations that evolve independently, increasing biodiversity

• contributes to volcanic activity and earthquakes, which can cause rapid environmental changes and mass extinctions

human influence

… that causes (much faster) species extinctions include habitat destruction, introduction of invasive species, pollution, overharvesting and hunting

causes of species loss

• natural

  • volcanoes

  • drought

  • meteors

  • ice age

• human influenced

  • habitat destruction

  • introduction of invasive species (Grey squirrel)

  • pollution (eutrophication)

  • overharvesting

  • hunting

factors used to determine the conservation status of a species

• population size

• degree of specialization

• distribution

• reproductive potential and behaviour

• geographic range and degree of fragmentation

• quality of habitat

• trophic level

• probability of extinction

International Union of Conservation of Nature (IUCN)

the Red list of endangered species is published by

tropical biomes

… contain some of the most globally biodiverse areas and their unsustainable exploitation results in massive losses in biodiversity and their ability to perform globally important ecological services

Most … occur in less economically developed countries, therefore there is conflict between exploitation, sustainable development and conservation.

Tasmanian tiger

extinct species

Iberian lynx

critically endangered species

American bold eagle

species whose conservation status has been improved by intervention

1. tropical rainforest

2. coral reef

3. mangrove forest

3 biomes found in the tropics

1. stop erosion

2. natural filter

3. provide shelter

4. carbon sinks

4 services provided by mangrove forests

CITES

international governmental legislation to control species movement at the borders

(species based conservation)

streangths of CITES

• ensures international animal trade doesn’t harm endangered species

• wide-ranging

• 3 levels of protection

• legally binding

• international

weaknesses of CITES

• voluntary

• low penalties

• lacks own financial mechanism

• downlisting may have negative impact (African elephant)

streangths of zoos

• educate public about need for conservation

• breeding programs increase populations while ensuring genetic diversity

• provide proper diet and controlled environment

• protect against disease

weaknesses of zoos

• reentroduced animals can have problems surviving in the wild

• not all species breed well in captivity

• ethical issues

• created habitats are different from natural habitats

flagship species

charismatic species selected to appeal to the public and therby help protect other species in an area

charismatic species

aestetically pleasing animals

• dreadging

• removal of mangrove forests

• starfish

• sugar cane plantations

• coral bleaching (global warming)

• pollution

6 threats to biodiversity of the Great Barrier Reef from human activity

1. aeshetic

2. ecological

3. economic

4. ethical

5. social

5 types of reasons for conservation of biodiversity

Intergovernmental organisation

EEA, UNEP, IUCN

• enforces desicions for biodiversoty conservation via laws

• slow to respond

• may be against public opinion

• possibly politically or economically driven desicions

• financed by national budget

(give 3 examples)

Non-governmental organisation

Greepeace, WWF

• enforces desicions for biodiversoty conservation via protests, public pressure and suing governments or bussinisses

• fast to respond

• radical - often met with negativity

• financed by private donations

(give 2 examples)

in-situ conservation

conservation of species in their natural habitat

(nature reserves, conservation areas)

ex-situ conservation

conservation of species outside their natural habitat

(botanic gardes or zoos, captive breeding, reintroduction programs)

• size

• shape

• edge effects

• buffer zones

• corridors

criteria for consideration when designing protected areas

(list 5)

• IGOs

• GOs

• bussinisses

• local people

• scientific research

human influence on protected areas

(list 5)

species-based conservation strategies

• CITES

• captive breeding and reintroduction programmes, and zoos

• selection of “charismatic” species to help protect others in an area (flagship species)

• selection of keystone species to protect the integrity of the food web

Danum Valley Conservation Area

• tropical rainforest biome

• North East Borneo in Malaysa and Indonesia

• 43800 hectares

• Malaysan and Ingodensian government + Royal Society in UK + Sticky Rice Travel Tourism company

  • large protected area

  • corridors between two other conservation areas

  • managed by locals

  • surrounded by bufferzone

  • variety of habitats

  • endangered species:

    • Western tarsier

    • Sunda pangolin