Changes to Populations Flashcards
(17 cards)
What are population dynamics?
The measurement of the size of the population and the factors that can be considered that cause changes to occur
What are the key factors affecting population dynamics?
Birth and death rate
Immigration and emigration
Carrying capacity
Predation and competition
Environmental changes
What are the factors that determine if a population will rise or fall?
A stable food supply
Animals free from disease
Habitat availability
A good ratio of males to females
A large proportion of males and females at breeding age
Good weather conditions
What five main factors cause fluctuations in wildlife populations?
Migration
Climate change
Emerging diseases
Habitat destruction
Influence of man
What is migration?
The movement of an individual or a group of individuals from one habitat to another across a large distance
What positive impact can migratory species have on global ecosystems?
Contribute to genetic diversity and ecosystem resilience while also transporting nutrients across ecosystems enriching the soil and water sources
What negative impact can migratory species have on global ecosystems?
Interact with resident populations affecting food chains and competition for resources
Disrupted migration patterns can lead to population declines and habitat imbalances
Some species migrate in response to climate change altering ecosystem dynamics
Human-induced migration sometimes leads to invasive species disrupting native ecosystems
What is climate change?
A long-term change in the average weather patterns that have come to define Earth’s climates
What has caused climate change to occur?
Driven by human activities which increase heat trapping greenhouse gas levels in Earth’s atmosphere, raising Earth’s average surface temperature
What impact does climate change have on global ecosystems?
Melts polar icecaps and glaciers causing sea levels to rise which encroaches on coastal habitats and the artic tundra
Changes in rainfall patterns leads to droughts and flooding
Carbon dioxide concentration in the oceans and seas are leading to higher water temperatures which causes mass coral bleaching
Changes in weather patterns lead to changes in natural cycles and events
More frequent and severe natural disasters
What are emerging diseases?
New or increasing illnesses or infections in a new area
What impact do emerging diseases have on global ecosystems?
Biodiversity loss which leads to reduced genetic diversity and ecosystem imbalance
Disruption to food chains as well as the spread of zoonotic diseases due to the increase contact between humans and wildlife
Diseases affecting habitats causes environmental changes like deforestation
What is habitat destruction?
The physical removal or vandalism of a habitat
What impact does habitat destruction have on global ecosystem?
Loss of biodiversity
Forests, wetlands and coastal areas provide essential services like carbon dioxide absorption and water filtration, their destruction weakens these natural processes
Deforestation reduces the planets ability to absorb carbon dioxide exacerbating global warming
Disruption of breeding and nesting grounds
What is influence of man?
Humans having the power to have an effect on global ecosystem
What positive impact can humans have on global ecosystems?
Efforts to mitigate threats to global ecosystems include conservation initiatives, sustainable practises and policies aimed at reducing environmental harm
What negative impact can humans have on global ecosystems?
Urbanisation, deforestation and agriculture lead to habitat destruction
Air, water and soil pollution disrupt ecosystems affecting wildlife and plant health
Climate change, caused by human activities, alters weather patterns and ecosystems
Overexploitation of resources such as overfishing, hunting and mining, threatens the survival of species
Invasive species introduced by human activity can outcompete local wildlife
