Topic 7 C Flashcards
(12 cards)
What is an ecosystem?
All the organisms living in a community
What is a niche?
Role of a species within a habitat
What is a population size?
Number of organisms of one species in a habitat
What is a population?
All the organisms of one species in a habitat
What is a community?
Population of different species in a habitat
How does the mark release recapture work?
Capture a sample and count, mark them with a harmless marker, release back into habitat, wait a while to allow to mix back into society and take a second sample, count how many marked
What is the equation to use to estimate population size during mark release recapture?
Number caught in first sample x number caught in second sample/ number marked in second sample
What is primary succession?
When a species colonise a new land surface, seeds and spores blown in and grow, pioneer species, abiotic conditions are harsh and only pioneer species can grow as they are adapted, die and decompose forming a basic soil, conditions less hostile allowing other species to move in and grow, these die adding more organic bacteria. nitrogen fixing bacteria turn nitrogen into ammonia which can be used by plants to allow them to grow
What happens at later stages of succession?
Different plants and animals that are better adapted for each condition move in and out compete and become the dominant species. They cause the most change. Ecosystem becomes more complex and diversity increases
What is a climax community?
When the ecosystem is supporting the largest most complex community it can, wont change much more
What is secondary succession?
Happens on land that has been cleard of all plants but soil remains, starts at a later stage
What are the conservation methods?
Management of succession, seed banks, captive breeding, fishing quotas and protected areas
