Populations and Sustainability Flashcards
State the 3 stages of a sigmoidal population growth curve
Slow growth
Rapid growth
Stable state - carrying capacity
State the features of slow growth in a sigmoidal population growth curve
small number of organisms
slow increase
State the features of rapid growth in a sigmoidal population growth curve
exponential increase
no constraints to limit population increase
State the features of stable state in a sigmoidal population growth curve
reached carrying capacity
further increase prevented by external constraints
birth rate approx. = death rate
Define carrying capacity
size of a population that an ecosystem can support
Define limiting factor
A factor that prevents a population from increasing above carrying capacity
Name 3 biotic limiting factors
predators
disease
competition
Name 5 abiotic limiting factors
temperature water soil ph light intensity space humidity
Describe the 3 stages of how intraspecific competition changes population size
1- population increases
food and resources plentiful
more individuals survive and breed
2- population decreases
increasing intraspecific competition for food and resources
death rate > birth rate
3 - population increases
fewer organisms now competing
more individuals survive and breed
Define immigration
Individuals moving into an area
Define emigration
Individuals moving out of an area
Define density-independent factors
tend to be physical
have major effect regardless of population size
eg. fire/flood/light intensity
Define density-dependent factors
impact is proportional to size of population
eg. disease, competition
define the competitive exclusion principle
If 2 species are competing for the same resources, that which is less well-adapted will be outcompeted
Define conservation
Maintenance of biodiversity through human action or management
Define reclamation
restoring ecosystems that have been damaged or destroyed
Give an example of reclamation
controlled burning, halts succession - increases biodiversity
State 3 aims of conservation
maintains:
- diversity between species
- genetic diversity within a species
- habitats
Define preservation
restricting or banning human interference so ecosytsmes are kept in their original states
Give an example of a preservation technique and where it could be used
No visitation eg. nautire reserves or marine conservation zones
Give one social, economic and ethical importance of conservation/preservation
economic - maintains resources and sources of income over a long period of time
social - able to continue enjoying natural beauty 0 benefits to wellbeing
ethical - we should not have a right to interfere and destroy ecosystems - moral responsibility for the future
Outline a small scale sustainable timber production technique
Coppicing/pollarding
cut back trees to stump/ trunk
trees re grow in 7 - 20 years
done on rotation
why is rotational coppicing/pollarding beneficial?
maintain biodiversity by creating a large range of habitats
allows consistent income
Outline a how a large scale timber production technique can be sustainable
logging
- replace trees
- cut down biggest trees only
- don’t replant too close together
- inspect trees regularly for pests/diseases
- leave some areas undisturbed
Outline the environmental disadvantages to unsustainable timber production
- soil erosion
- habitat loss
- reduced soil fertility
- new roads for trucks
- therefore air and noise pollution
What is the aim of sustainable timer production
forests managed to provide continuous supply of timber and maintain biodiversity
What is the aim of sustainable fishing
catching the maximum fish without a decline in fish population
Name 5 techniques used in ensuring sustainable fishing
Quotas Permits Mesh sizes Restrictions on unsustainable methods Sanctions/ penalties
State 2 disadvantages for imposing sustainable fishing practices
Difficult to monitor
Dead fish thrown back into sea so quota not breached
State some disadvantages to land based fish farming
disease
small gene pool
expensive
ethical concerns
Name the 6 case studies for populations and sustainability
Masai Mara Nature Reserve - Kenya Terai Region - Nepal Galapagos Islands - Ecuador The Lake District - England Snowdonia National Park - Wales Peat bogs
What is the ecosystem like in the Masai Mara?
Savannah regions
Fertile regions close to river (rich grass and woodland)
Open plains far from rivers - trees and shrubs
Zebra, wildebeest, buffalo, elephants, leopards, lions, rhino
Acia - but many were removed to reduce habitats for disease vectors and via grazing/fires
How has ecotourism affected the masai mara?
ecotourism - sustainable tourism - reduce impact and aid conservation
ADVANTAGES:
- does not exploit environment or communities
- consults locals on developments
- ensures infrastructure benefits locals too
DISADVANTAGES:
-use fo trails and transport - soil erosion and habitat changes
Outline a conservation effort in the masai mara
Protection against black rhino poaching
- employment of rangers, given communication equipment, vehicles etc.
SOC and ECON benefit to locals, ENV benefit to rhinos
Population has since increased
Outline the human impact to the masai mara via farming activity
Live stock grazing -increase in population has led to more cattle - increased soil erosion - now limited to edges Cultivation -increased recently -converts grassland to cropland -reduces nutrients in soil so reliance on fertilisers
Outline 4 ways the Masai Mara ecosystem is is changing/ being managed
elephants - threaten cultivation - trampling/eating -fenced but not good for migration hunting - cull excess animals - maintains populations - but must be constantly monitored livestock - migratory wildlife compete eg. with wildebeest for grass - diseases introduced/spread humans - more homes, cattle, land - wildlife density declines
What is the ecosystem like in the Terai Region?
subtropical plants - pipal and bamboo
bengal tiger, sloth bear and Indian Rhino
Large areas have been cleared for agriculture
- exacerbated monsoon flooding
Outline the forest management in the terai region and its impact
conservation of forests steady income - increased development local forestry groups -set prices, rules and rates - FSC
- -improvement in conservation and biodiversity
- soil and water management
- increased retail price, increase econ. input
- increased employment
- sustainable wood fuel sources provide (3/4 of household needs)
Outline the methods for promoting sustainable agriculture in the Terai region
- fruit and veg in hills and mountains - avoids intensifation of terai
- irrigation - enhances crop production
- cropping - no monocultures
- N-fixing crops eg. pulses and legumes enhance fertility
- crop varieties - resistant to soil, climatic or biotic changes
- Fertilisation techniques - increase yield
All create max yield with current space, prevent further loss of biodiversity, allow more econ. income etc.
What is the location and significance of the Galapagos islands?
Pacific, ecuador
never been connected to mainland, flora and fauna had to survive crossing the ocean
Speciation/adaption between islands different
Name 5 management techniques in the Galapagos
introduction of park rangers limiting human access controlling migration strict control of introduction of animals national park established
What animals are present in the galapagos
Mostly reptiles
Only mammal is the Galapagos rice rat (arrived on floating vegetation)
Flightless cormorant - reduced wings - better fishing underwater - no need to fly to escape mainland predators
marine iguana - can swim - black and dark grey - heat lots in sun so can swim for food for longer
What plants are present in the galapagos
Costal - salt toleretn species eg. mangrove/saltbush
Arid - drought tolerent species eg. cacti/carob tree
Humid - dense cloud forest - mosses and liverworts
How has historic human activity impacted the galapagos
Whaling trade disrupted the ecosystem
Islands used as stop over points
Domestic animals roamed free
Forests chopped down for fires to render whale fat
Tortoises removed for food
Goats were introduced - outcompete tortoises
What are peat bogs and what is their importance?
wet spongy ground made from dead vegation
carbon sink - store of co2
preservation important for climate crisis
How are peat bogs formed?
Dead material can not decompose
acidic and anaerobic conditions
wet and boggy areas
What animals and plants are present in peat bogs?
Insects - butterflies, moths, dragonflies
Few predators - birds often nest
Plants adadpted to wet environment with few nutrients:
Sphagnum mosses, Bog cotton, Heather, Cotton sedge
How do we conserve peat land?
Leave it undisturbed and as wet as possible
– ditch blocking to raise water levels
Tree removal
– high water requirement, reduce ability to support bog vegetation
Controlled grazing
Remove threats
– eg. don not let me drained for agriculture of harvested for gardening
RSPB
–conserve ecosystem
Why has tourism to our UK case studies increased?
Increased awareness from media
less access to green spaces
obvious tourist routes
exercise and wellbeing
What the advantages and disadvantages to increased tourism to our UK case studies?
AD: economic (local) aware of personal impact on environment DIS: -disruption to local habitats - pollution (noise, light, air) - littering/waste -soil erosion to paths
What animals and plants are present in Snowdonia
coastal and estuary birds
forest birds
moorland and mountain birdds
badgers, voles, deer and hedgehogs
snowdon lily, oak, alder, witchelm
What animals and plants are present in the lake district
water vole, toads, bats, deer, red ssquirrells
vendance - endangered and only found here
purple saxifrage, dwarf juniper, dwarf willow, alpine cinquefoil, sundew
How can we control human activity in Snowdonia/ the Lake district
Fixed paths for walking
Limit areas for cycling or quad biking
Visitor centre to educate - litter, keeping to paths…
Warning about invasive species eg. mud on boots carrying seeds or pathogens
Park rangers
LAkes
Permit on taking boats out and control on fishing
reason of importance and location - antarctica
southern most contient
remote and ice covered
contains 70% of worlds fresh water
carbon sink
State 2 threats to antartica
Global warming
increased tourism
Why may tourism have increased in antarctica?
cheaper travel
increased awareness
research
more accessible
WHat are the advantages and disadvantages to increased tourism to antarctica?
- more awareness
- more research
- better conservation
- more money
- damage to sensitive habitats
- pollution
- waste
How is the antarctic being managed
Antarctic treaty - 1961 ban on hunting controlled fishing restrictions on waste disposal removal of dogs permits for human access
