Module 6: Populations and Sustainability: Flashcards
Population Growth Curve: Phase 1
Lag phase, small founder population with a birthrate greater than death rate.
Population Growth Curve: Phase 2
Exponential growth phase: population produces at the maximum breeding rate, no constraints on population increase.
Population Growth Curve: Phase 3
Stationary phase, oscillating around mean population size. Birth rate is approximately equal to death rate meaning the population has reached its carrying capacity.
What are limiting factors of Population Growth:
Factors that limit and reduce a populations size or capacity to grow.
Density independent Limiting Factors of population growth:
Abiotic Factors
Density dependent Limiting Factors of population growth:
Biotic Factors
What effects the impact of most biotic factors on population growth?
The size of the population.
What are the two types of competition?
Interspecific Competition and Intraspecific Competition
Interspecific Competition:
Competition between populations of DIFFERENT species.
Reduces the level of a resource for all involved species.
Results in smaller populations
Better adapted species outcompetes other species
Competitive exclusion principle
What is the competitive exclusion principle?
The elimination of less well adapted species due to their competitive disadvantage
Intraspecific Competition:
Competition between individual of the SAME species.#
Competition for the same resource, e.g breeding territory
Fluctuating population size
Predation is an example of which type of limiting factor?
Density Dependent Factor (biotic)
What two populations are interlinked in predation?
Predator and Prey
What is the factor effecting the population of the predator in predation:
Intraspecific competition caused by varying population of prey.
What are the 3 reasons for conservation?
Economic, Social and ethical
Define Preservation:
The protection of an ecosystem by restricting or banning human activity, to keep the ecosystem in its original state
What reasons may an ecosystem be preserved?
Ecological sensitivity, Archaeological sensitivity and paleontological sensitivity.
The ecosystem may be unstable and easily damaged or destroyed.
Aims of sustainable management:
- Conserve ecosystem
- Ensure future resource availability + healthy lives for humans
- Provide wealth to countries with natural resources to sustainably develop.
- Efficiently using finite resources.
What is conservation?:
The active dynamic management of biodiversity in ecosystems through human action.
What is sustainable development?
The sustainable use of natural resources to ensure their longevity.
What is reclamation?
The restoration of damaged/destroyed ecosystems.
Name some disadvantages of reclamation:
- Time consuming
- Expensive
- Difficult to reintroduce species
Two types of sustainable timber production (small scale)
Coppicing and Pollarding.
What are the goals of sustainable management of forests and woodlands?
Maintenance of biodiversity
Maintenance of timber supply
maintenance of economic viability of timber production
What is the large-scale sustainable timber production method:
Planting and felling trees.
Coppicing:
Exploits capacity of species to produce new shoots from stumps or roots
Young tree stems repeatedly cut down to near ground level leaving a stump (stool)
Regrow after number of years
Pollarding:
Upper branches cut - new growth out of reach of animals
Used for wood
Used to feed livestock
Fodder Pollards:
- pollard hay
- upper branches pruned every 2-6 years to increase the leafy material
Wood Pollards:
longer intervals of 8-15 years
produce upright poles - good for fence rails and posts.
Concerns around unsustainable fishing practices?
- Heavy fishing pressures (overfishing) -> significant loss of potential yield
- Stock structure will erode to where it loses diversity
- Ecosystems and economy surrounding it will both decline.
Sustainable Fishery:
A fishery that is harvested at a sustainable rate, where the fish population does not decline over time because fishing practices.
Sustainable fishery management techniques:
Conventions Marine protected areas Fish farming International agreements on landing quotas public awareness campaigns
Galapagos Islands: Animals
Giant Tortoise
Flightless cormorant
Marine iguana
Galapagos Islands: Ecosystem
Volcanic Islands - humid and warm
Galapagos Islands: What are the 3 zones?
Coastal Zone
Arid Zone
Humid Zone
What has caused the Galapagos Islands to be sensitive:
19th century - whaling
- introduction of invasive species (goats)
- Deforestation
- Isolation
Galapagos Islands: Conservation
1959 National Park:
- Introduction of park rangers
- Limiting access
- Controlling migration of species
Antartica: Ecosystem
Cold, dry, high, tundra
Antartica: Plants
Moss, algae, Lichness
Antartica: Animals
Seals, Whales, Penguins, Polar bear
Galapagos Islands: Plants
Cacti - arid zones
Mangrove - coastal zone
Moss - humid zone
Antartica: Control of human activities
Antartica Treaty 1961:
- Scientific Cooperation
- Protection of environment
- Conservation
- Management of protected areas + tourism
Snowdonia: Ecosystem
Lake and Ancient woodland - cold and mountainous
Snowdonia: Animals
Coast + Estuary Birds -> cormorants
Forest Birds -> pied flycatcher
Moorland + mountain bird -> Ospreys
Snowdonia: Plants
Snowdon lily
Oak
Snowdonia: Control of Human Activity
1951 National Park: Some areas preserved. Conservation and enhance natural beauty Education Enhance economic and social wellbeing of local communities
What is an environmentally sensitive ecosystem?
Fragile ecosystems that are less resistant to changes to the environment.
Methods to protect environmentally sensitive ecosystem?
- Limiting the access of areas
- Controlling movement of livestock
- Anti-poaching measures
- replanting of forests and native plants
- Limiting hunting (seasonal bans)
Lake District: Ecosystem
Mountainous with lakes. Dales and fringes of lakes provide variety of habitat including ancient woodland.
Lake District: Animals
Bats. red deer. golden eagle
Lake District: Plants
Specialised trees e.g dwarf juniper and dwarf willow
Lower region -> sundew (carnivorous plant)
Lake District: Control of human activity
Area is conserved whilst allowing tourism
Active management of the countryside - e.g replanting native tree species
Masai Mara: Ecosystem
Primary Ecosystem: Savannah
Previously abundant in acacia but tsetse fly acted as a vector for sleeping sickness and-so the acacia was removed.
Masai Mara: Land use
Farming
Cultivation
Conservation of species
Masai Mara: Farming
Farming:
- Grazing of livestock -> used semi-nomadic farming -> allowed land to recover
- Grazing now limited to edge of reserve -> less freedom -> land can’t recover -> soil erosion.
Masai Mara: Cultivation
Cultivation
- Grassland -> crop land
- Rely on fertilisers -> soil nutrients used up
Masai Mara: Ecotourism
Relies on tourism for economic input
Ecotourism-tourism directed towards natural environments to support local communities.
Masai Mara: Animals
Black Rhinoceros
What are the 3 principles of ecotourism:
- No exploitation of the reserve or local communities
- Engagement with local communities about development
- Infrastructure development benefits both tourism and local communities.
Masai Mara: Strategies to conserve black rhino
- Balance needs of wildlife and community
- Deter poaching
- Communication equipment, vehicles + infrastructure supplied reserve rangers.
Masai Mara: Elephant conflict
Threaten cultivation -> trampling + damage
Controlled by fencing land -> However reduces natural migration
Masai Mara: Legal Hunting conflict
- Culls excess animals -> maintains populations
- Populations must be actively monitored to maintain balance.
Masai Mara: Livestock conflict
Fencing off livestock threatens migratory wildlife, however not fencing them off increases the risk of diseases spreading. e.g wildebeasts.
Masai Mara: Human Population Growth
The growth of the population means that their needs to be increased land use for cultivation and livestock. Smaller space available due to reserve -> no longer nomadic -> soil nutrient deplete -> use fertiliser.
Terai Region of Nepal: Ecosystem
Hot and humid in summer months. Fertile soil. Area of extreme biodiversity. Forest region.
Terai Region of Nepal: Animals
Bengal Tiger, sloth bear, and indian rhinoceros
Terai Region of Nepal: Plants
Bamboo and pipal
Terai Region of Nepal: Sustainable forest management in Nepal: Aim
- To provide a sustainable livelihood for local people
- To ensure the conservation of forests
- To provide nepal with sustainable economic investment.
Terai Region of Nepal: Sustainable forest management in Nepal: Method
- Local community forestry groups and cooperative networks e.g FSC
- National legislation
Terai Region of Nepal: Sustainable forest management in Nepal: Successes
- Significant improvement in the conservation of the forested regions both in the terms of increased area and improved density.
- Improved soil and water management across the region
- An increase in the retail price of forestry products, and so a greater economic input to the region
- Employment and income generation through forest production.
- Sustainable wood fuel sources, which contribute three-quarters of the local household energy needs.
- Securing the biodiversity of the forested areas.
Terai Region of Nepal: Promoting sustainable agriculture: Strategies
- Promoting the production of fruits and vegetables in hills and mountain regions
- Improving irrigation facilities to enhance crop production
- Multiple cropping, where more than one crop is grown on a piece of land each growing season.
- The growth of nitrogen-fixing crops such as pulses and legumes to enhance the fertility of the soil.
- Growing crop varieties resistant to various soil, climatic and biotic challenges through the use of modern biotechnology and genetic engineering
- Improving fertilisation techniques to enhance crop yield.
Peat Bogs: Ecosystem
A Wetland region of wet, spongy ground. Large areas of open ground.
What is a peat bog?
A region of wet, spongy ground that contains decomposing vegetation that’s acidic and anaerobic conditions prevent full decay. This causes peat bogs to be carbon sinks (carbons stores).
Peat Bogs: Plants
Mosses, sedges and shrubs
Peat Bogs: Animals
Butterflies, moths, dragonflies -> lack of large predators.
Birds.
What region do plants grow in Peat Bogs?
Peatland
Peat Bogs: Threats to ecosystem
Extraction of peat to supply gardeners and nursery growers.
Afforestation
Agricultural intensification (land drainage)
Peat Bogs: Reasons for conservation:
Retain carbon stores to further reduce impact of climate change.
Flood management and erosion control.
Peat Bogs: 4 methods of conservation:
- Conservation work of organisations e.g The wildlife trusts.
- Removal of seedling trees from the area
- Controlled grazing of peatland
- Ensuring peat and vegetation of the bog surface is undisturbed and wet.
Peat Bogs: Removal of Seedlings
Trees have a high water requirement due to transpiration. Therefore seedlings, that have the potential to remove water from an area of peatland and support for bog vegetation, must be removed.
Peat Bogs: Controlled Grazing
Grazing ensures a diverse wetland surface in terms of structure and species composition. This provides a wide range of habitats for rare insect species.
Peat Bogs: Ensuring peat and vegetation of the bog surface is undisturbed and wet.
To keep peat and vegetation undisturbed and watered:
Ditch blocking may be used to raise the water table to the bog surface.
What is the difference between sustainable and unsustainable timber production?
Sustainable timber production as many trees are planted as cut down.
Unsustainable Timber production removes trees without replacing them.
Define Carrying Capacity:
The maximum stable population size of a species that an ecosystem can support.
