Population And Sustainability Flashcards
0
Q
Threats to the Galapagos
A
- increasing population from tourism as more jobs= more pressure more waste
- over fishing- quotas met lots of opposition
- tourism- stricter measures needed
- exotic species- bring goats/rats eating vegetation/eggs
1
Q
Galapagos (captive breeding)
A
- 14 giants tortoises left
- 100 offspring released
- only successful if habitat maintained
2
Q
Galapagos conservation projects (project isabela)
A
- specifically trained hunters to lower goat population
- ‘judas’ goats released with trackers to find the rest
- complete by 2006
- vegetation returned
- endangered insects improved
- tortoises pop improved
3
Q
Endemic species
A
- found in only one are or country
- ie galapagos islands
4
Q
- increasing forrest efficiency
A
- matching the tree to the conditions
- the optimum distance between each tree
- control pests and pathogens
- use all the tree ie for fuel
- very best use of land
5
Q
Long rotation time
A
- leaving sections of the forrest for many years before re-foresting
- time for species variation to build up
- less disturbance from machinery
- although less cost effective
6
Q
Selective cutting
A
- felling only largest/most expensive trees
- although some disruption minimum + habitat maintained
- good on slopes prevents erosion unlike clear felling
- & maintain nutrients in the soil
7
Q
Clear felling
A
- removal of all trees from an area at once
- not gd for the ecosystem
8
Q
Sustainable forestry
A
- can mean removing timber in a way such that it will still be available in years to come
- or maintaining the ecosystem
- ie selective cutting or long rotation time
9
Q
Coppicing
A
- doesnt destroy woodland
- may improve biodiversity
- cut at the base and new stems available to grow
- small in diameter though
- plus labour intensive and not very cost effective
10
Q
Rotational coppicing
A
- coppicing different areas each year to allow them to grow
- good for biodiversity
- allows light to woodland floor
11
Q
Coppice with standards
A
- some trees in each area not cut & allowed to grow full ie standard
- after can be replanted or coppiced
12
Q
Reasons for conservation
A
- economic - so constant timber supply forever + ie fish levels
- social - tourism + jobs + happiness
13
Q
Conservation
A
- the active management of habitats in order to maintain/ increase biodiversity
- not necessarily a natural process
14
Q
Biodiversity
A
- range of habitats & communities & species in an area & the genetic variation that exists within each species
15
Q
Interacting factors
A
- different factors together tend to control poo size& distribution
- ie barnacles
- not too high temp change to much dependent on high/low tide
- not too low not enough rock space + predation
- not much balanus & chthalmus together as balanus grows faster
16
Q
Interspecific competition
A
- competition between organisms of different species
- when the niche of 2 organisms overlap
- bigger overlap= bigger competition
- can out compete so do co-exist
17
Q
Niche
A
- the role or position of an organism in an ecosystem
- ie habitat abiotic/biotic factors it affects/affects it
18
Q
Intraspecific competition
A
- competition between members of the same species
- important in limiting pop size - part of natural selection
19
Q
Competition
A
- when 2 organisms require a resource that is in short supply
20
Q
Predator-prey relationships
A
- prey pop increase = increase predator pop as more food
- limits prey pop + more comp for food = predator pop falls
- as predator pop decrease - prey pop increases
- rare as - predator only has 1 prey
- if predator is the main limiting factor for prey
- & food = max limiting factor for predators
21
Q
Carrying capacity
A
- the upper limit on size of a population that can be sustained
- tends to be caused by a collection of factors
22
Q
Sigmoid growth curve
A
- the patter of growth shown by many organisms when first introduced to a new enviroment
- ( lag phase then log phase)
- ie pop of a microorganism in a closed system
23
Q
Limiting factor
A
- anything that stops a population from increasing in size
- ie food availability/predators/parasites/nesting sites
24
Population
- a group of organisms of the same species that live in the same place at the same time & can interbreed
