ESS topic 3

Biodiversity

is the total diversity of living systems and exists at several levels. It is a result of habitat, species, and genetic diversity

Habitat diversity

the range of different habitats in an ecosystem or biome which is associated with variety of ecological niches

Species diversity

the variety of species per unit area that includes numbers of species present and their relative abundance

Genetic diversity

The gene diversity within one species or all species within an area. Occurs because of genetic mutations which can result in beneficial altered genes

Theory of evolution

the cumulative changes in the genetic composition of a species over many successive generations and explains how these changes give rise to completely different species to the common ancestor

Natural selection

process by which individuals with traits better suited to their environment are more likely to survive, reproduce, and pass on those advantageous traits to the next generation. This mechanism drives evolutionary change and is fundamental to the development of biodiversity.

Species evenness

the relative abundances of all species.

Endemic species

species not found anywhere else

Direct Threats to biodiversity

overharvesting, poaching, and illegal pet trade

CITES

Convention on International Trade in Endangered Species, which acts to prevent illegal trade in wildlife

Indirect Threats to biodiversity

Pollution, habitat destruction, climate change, and introduction of invasive species

Invasive species

species introduced to an area and then have to compete with endemic (native species) which can lead to extinction of the native species.

IUCN Red List

a book that assesses the conservation status of particular species to highlight plant and animals threatened with extinction

Factors used to determine Red List conservation status

Number of individuals, Reduction in population size, Geographical range, distribution, breeding potential

Known threats of species

degree of habitat fragmentation, quality of habitat

IUCN examples

Falkland Island wolf (extinct), Iberian Lynx (critically endangered), American Bald Eagle (Improved by intervention)

The tragedy of the commons

a paper which explains how short-term interest of the individual can lead to overconsumption of common natural resources at the expense of a broader society.

Economic arguments for conservation

often focuses on the value of ecotourism, genetic resources and commercial considerations of its natural capital. Species and habitat preservation also provide economic value as it maintains genetic diversity so that genetic resources will be available in the future.

Ecological for conservation

healthy ecosystems are more likely to provide ecosystem services such as pollination and flood prevention. For example, rainforests are vital to the hydrologic cycle and they stabilize the world’s most fragile soils by preventing erosion. Rare habitats should be conserved as they may contain endemic species that require specific habitats.

Aesthetic arguments for conservation

species and habitats are nice to look at and provide beauty and inspiration

Ethical arguments for conservation

include intrinsic and instrumental value of the species. Everyone has a responsibility to protect future generations and every species has the right to live

Social arguments for conservation

highlights the importance of goods and services for the well-being of humans, as many indigenous people rely on natural ecosystems

Conservation

means “keeping what we have” and aims to protect habitats and ecosystems, and hence species, from human-made disturbances such as deforestation

In-situ conservation

is the conservation of species in their natural habitat, which enables endangered species to be conserved in their native habitat.

Ex-situ conservation

the preservation of species outside their natural habitat, which includes captive breeding and reintroduction programmes.

Ex-situ and in-situ comparisons

species based conservation are that it attracts attention, and therefore funding for conservation and successfully preserves vulnerable species. Protected areas protect the whole ecosystem and the complex interrelationships that exist there

Edge effects

the edge of a protected area, there may be a change in abiotic factors, such as windier or warmer conditions compared to the interior. Edge effects may attract species not found in the deeper reserve and may attract exotic species from outside the reserve

Edge effects diagram

Buffer zones

managed or undistributed areas that can be identified around conservation areas

Rewilding

aims to restore ecosystems and reverse declines in biodiversity by returning an area to its natural processes and wildlife