Topic 3.3 Biodiversity Flashcards
Species definition
A group of organisms that can reproduce with each other to produce fertile offspring.
Biodiversity definition
The measure of the variety of living organisms in a habitat and their genetic diversity.
Abiotic factors
-Air
-Temperature
-Minerals
-Salinity
-Light intensity
-Soil pH
-Water
-Humidity
-Turbidity
-Soil composition
Biotic factors
-Predation
-Food availability
-Competition
-Mutualism
-Parasitism
-Disease
Species richness
The number of different species in an area.
Species evenness
Relative numbers of different types of organisms (calculate the proportions of each species as a percentage of the total abundance).
Index of diversity
Species richness and abundance are both taken into account in a formula
The Simpson’s Diversity Index formula
d= diversity index
N= total number of organisms
n= total number of organisms of each species
Σ= sum of
What might cause e biodiversity measurements to vary across the world?
-Natural events (eg. floods)
-Climate change (eg. severe drought)
-Abiotic factors
-Human activities (eg. deforestation)
-Time of day sampled
-Areas with higher photosynthetic rate
-Time of year sampled
Endemic species
A species is classified as endemic to an area if it is found nowhere else in the world.
To be classified as a hotspot area it must have 1500 endemic species.
Genetic diversity
The total number of different alleles in the gene pool of a population.
The greater the number of different alleles within a population, the greater the genetic density of that species.
Gene pool
Refers to the combination of all genes (including alleles) present in a reproducing species.
A large gene pool has extensive genomic diversity and its better able to withstand environmental challenges.
Describe the link between genetic diversity and species survival
-Traits that make them resilient
-Drop in genetic diversity can lead to extinction
-Genetic bottleneck occurs when a population is greatly reduced in size
-The greater the genetic diversity, the more likely the species will be able to adapt to environmental change.
Ethical
-Denying future generations to use renewable recourses if biodiversity is destroyed
-Nature is a source of pleasure for some
-Human activities could cause mass extinction due to global climate change
-If biodiversity is lost when a species becomes extinct, unique combinations of DNA are lost.
Economic
-Ecosystems provide us with fibres for clothing
-Ecosystems help maintain air quality
-A healthy ecosystem is important for human health and wellbeing
Provisioning services
-Food
-Medicines
-Fuel
-Fibres for clothing
Regulating services
-Pollination
-Pest control
-Prevention of soil erosion
-Sewage treatment
-Climate regulation
Supporting services
-Cycling of carbon
-Cycling of nitrogen
-Soil formation
-Nutrient cycling
Conservation
The protection of a species or an area/habitat to prevent damage.
Ways humans reduce biodiversity
-Illegal wildlife trade
-Overfishing
-Population (increase), growth in consumption
-Pollution
-Destruction of natural habitats
-Climate change
Ways to improve biodiversity
-Consume less and more responsibly
-Eat meat and dairy responsibly
-Reduce food waste
-Education (or future generations)
-Walk shorter journeys
The five threats to biodiversity
-Land and sea use change
-Pollution
-Species overexploitation
-Climate change
-Invasive species and disease
In-situ conservation
The conservation of a species in its natural habitat and the maintenance and recovery of viable species in their original surroundings.
Examples of in-situ conservation
National parks, sanctuaries, natural reserves.
Ex-situ conservation
The conservation of components of components of biological diversity outside their natural habitats.
Examples of ex-situ conservation
Aquariums, botanical gardens, DNA banks, zoos
Seed bank
A place where seeds are stored and to preserve genetic diversity for the future. They are usually in flood, bomb and radiation-proof vaults holding jars of seeds from a different plant species. The seeds are typically kept at low humidity and cold conditions.
Advantages of in-situ conservation
-It conserves species and its habitat
-Ecosystem integrity is also maintained as the species are able to play a vital role in the functioning of the ecosystem
-Cheaper than ex-situ
-Protects the biodiversity and the crucial elements of the ecosystem.
Disadvantages of in-situ conservation
-The habitat may be too fragmented to ensure a sustainable population
-Too much genetic diversity may have been lost to allow change in in their natural environment
-Wildlife reserves may be damaged by ecotourism
-The conditions that caused the area to have a loss of species may still e present
Advantages of ex-situ conservation
-Protects organisms from predation and poaching
-Help attract funding and awareness
-Techniques such as artificial insemination are used to maximise reproductive success and genetic diversity.
Disadvantages of ex-situ conservation
-Limited genetic diversity
-It may be difficult to provide a suitable environment
-Many animals may also be unable to be reintroduced into the wild as they will not have learnt the necessary behaviour.
Ex-situ conservation in plants
-The genetic material of extinct species would be lost forever, which could possible be a disaster for human survival (plants are a vital importance to all our lives).
-Crossbreeding crop plants back to original wild plants, or using wild plants to supply genes for genetic engineering, are ways in which the longterm health of our crop plants can be maintained.
-Botanic gardens maintain collections of the world most interesting and unusual plants.
Conflict involved with in-situ conservation
-It costs money to maintain and conserve the area which could be spent on health and education
-People need the land to live and earn money, but their activities can lead to pollution, erosion and many other problems
-Many people struggle to survive snd need the land to grow food to feed themselves and their families
-Lack of complete control over many factors which influence the survival of individuals
-Fear of natural threats like predation and poaching
-Uncontrollable factors like diseases and climate change that could lead to extinction of a species.
How a site is chosen to be conserved suitable for in-situ (3 techniques)
The three main in-situ techniques are defined as genetic reserve, on-farm and home garden conservation.
Genetic reserve conservation
Genetic reserve conservation of wild species involves the location, designation, management and monitoring of genetic diversity in a particular natural location.
On-farm conservation
On-farm conservation involves the maintenance if traditional varieties by farmers in agro-ecosystems.
Home garden conservation
Home garden conservation serves as the refuges for crops and crop varieties that were one more widespread in the larger agro-ecosystem or that developed over generations in the gardens themselves, and they provide micro-environments for crop evolution.
Allele definition
Different forms of a particular gene, found at the same locus (position) on a chromosome. A single gene could have many alleles.
Why should we maintain biodiversity?
-More stable, resilient populations
-Ecotourism opportunities
-Provide sources of medicine
-Stabilise soils
-Increase the gene pool
