Biodiversity Flashcards
(44 cards)
What is biodiversity?
Biodiversity refers to the variety of living species on Earth, including plants, animals, bacteria and fungi.
When discussing biodiversity, what are the three main types of diversity?
- Species diversity
- Genetic diversity
- Ecosystem diversity
What is biosphere integrity?
Change that preserves the overall dynamic and adaptive character of the biosphere
What are the two subcomponents of biosphere integrity?
- Genetic diversity
- Function integrity
How is genetic diversity often measured?
As species extinction rate
How is function integrity measured?
As energy available to ecosystems (net primary production (NPP) and human appropriation net primary production (% HANPP))
What is the current status of the species extinction rate?
> 100 species per million species per year are going extinct. The pre-industrial value was 0.1-1 species per million species per year.
What are the different conservation statuses?
- Not evaluated (NE)
- Data Deficient (DD)
- Least Concern (LC)
- Near Threatened (NT)
- Vulnerable (VU)
- Endangered (EN)
- Critically Endangered (CR)
- Extinct in the Wild (EW)
- Extinct (EX)
How many species are threatened with extinction?
Roughly 42,100 species are threatened with extinction.
- amphibians: 41%
- mammals: 26%
- conifers: 34%
- birds: 14%
- sharks and rays: 37%
- reef corals: 33%
- selected crustaceans: 28%
How many species have gone extinct since 1500?
680 species
Which type of diversity is often overlooked?
Genetic diversity. “Keeping genetic diversity is important as there are some traits that might benefit humans”
What is genetic diversity?
Genetic differences between animals within species.
What are traits?
Specific characteristics of an organism
What is an ecological niche?
Matching of species to specific environmental conditions
Why is there an increase in tree cover?
Increase in tree cover is due to an increase in monoculture crops e.g. palm tree plantations in Indonesia. This is why tree cover has increased, however, habitat integrity has decreased.
What are the most vulnerable ecosystems in the world? Why?
- Tropical coral reefs: high sensitivity to present warming and ocean acidification
- Savannas: vegetation shifts due to increasing atmospheric CO2
- Tropical forests & high latitude and altitude ecosystems: vegetation shifts mainly due to drying
- Mediterranean-climate ecosystems: due to high levels of climate warming
- Coastal ecosystems (one of the most affected): due to multiple factors
Not only is there a decrease in diversity, but also _____?
Abundance
What is an example of decrease in abundance?
Insect biomass is experiencing 75% decline.
What impacts can a decrease in abundance have?
Decrease in abundance can lead to cascading effects on food webs and alter the functioning of ecosystems.
What indicators are used to measure biodiversity?
- Alpha diversity - mean species diversity in sites or habitats at a local scale (within habitat)
- Beta diversity - the ratio between regional and local species diversity (between communities) - this can be obtained by comparing the number of species unique to each ecosystem
- Gamma diversity - the total species diversity in a landscape (between habitats/in a region)
!! these indicators do not consider abundance !!
What indicator is used when monitoring abundance?
The Shannon Diversity Index - the higher the Shannon index value, the more diverse the community is, meaning both a variety of species and a more even distribution among them
What are direct drivers of biodiversity loss?
- Climate change
- Over-exploitation
- Pollution
- Land and sea use
- Invasive species
- Others
What are indirect drivers of biodiversity loss?
- Population demand (demographic and sociocultural)
- Economic demand (and technological)
- Institutions and governance
- Conflicts and epidemics
What are examples of declines in nature?
- Natural ecosystems have declined (47%)
- More species are being threatened with extinction (25%)
- Decrease in naturally abundant species (23%)
- Global biomass of wild mammals has decreased (82%)