Studied by 43 people
Simpson’s Diversity Index
a measure of diversity which takes into account the number of species present and the relative abundance of each species
Simpson’s Diversity Index formula
n = total number of organisms of a particular species
N = total number of organisms of all species
High values of D indicate a stable and ancient site
Low values of D indicate pollution, recent colonization or agricultural management
Standard deviation
T-test
tells you if you can trust your data
Biodiversity
The amount of biological or living diversity per unit area
e.g. This high level of biodiversity in the Amazon Rainforest contributes to its resilience, productivity, and ability to provide ecosystem services such as carbon sequestration, climate regulation, and water cycling.
Species diversity
The variety of species per unit area. Includes the number of species present and their relative abundance
Habitat diversity
The range of different habitats or number of ecological niches per unit area
Genetic diversity
The range of genetic material present
Threats towards biodiversity
Natural hazards
Loss of habitat
Fragmentation of habitat
Pollution
Agricultural practices
Overexploitation
Non-native species
Spread of disease
Factors used to determine conservation status
Population size
Reduction in population size
Number of matured individuals
Geographical range/degree of fragmentation
Quality of habitat
Factors making species prone to extinction
Limited distribution
Small population size
Habitat specialists
Low reproductive capacity
Poor competitors
Large mammals
Valuable products
Altruistic species
Position in the food chain
Umbrella species
large species that require a large habitat. if you protect their habitat, you also protect habitats for other species (e.g. the giant panda)
Flagship species
species selected to act as an ambassador or symbol for a campaign/environmental cause (e.g. panda for WWF)
Keystone species
species that interact in the food web and if lost, leads to the demise of other species. they protect the entire community (e.g. sea otters help the health of kelp forests but are vulnerable to predators, therefore risking kelp forests)
Speciation
occurs when a group within a species separates from other members of its species and develops its own unique characteristics
Natural selection
a natural process resulting in the evolution of organisms best adapted to their environment. Organisms that are more adapted to their environment are more likely to survive and pass on the genes that aided their success.
Geographical isolation
essential in the formation of a new species. Populations of the same species separate, cannot interbreed and start to diverge if the environments they inhabit change
Reproductive isolation
evolutionary changes to the appearance or behaviour of populations may result in males and females of those populations no longer being attracted to each other and therefore not breeding. the exchange of genes may slow and eventually stop, different species may arise
Constructive margins (plate activity)
the plates move apart from one another. When this happens the magma from the mantle rises up to make new land in the form of a shield volcano.
Destructive margins (plate activity)
The plates move towards one another and this movement can cause earthquakes. As the plates collide, the oceanic plate is forced beneath the continental plate.
Collision margins (plate activity)
when two continental plates move towards each other and collide. The land between the plates is forced upwards to form fold mountains
Conservative margins (plate activity)
the plates are moving past each other or move side by side at different speeds. As they move, friction occurs and become stuck. They are trying to move so pressures and stresses build up in the crust. When the pressure is released suddenly, waves of energy move through the crust, causing an earthquake.
Soil ecology
Horizons
layers of soil
Horizon O
organic - ecosystem litter, hummus, organisms
Horizon A
topsoil - decomposing organic layers
Horizon E
subsurface - depleted organic
Horizon B
subsoil - clay
Horizon C
parent material - loose rock
Horizon R
bedrock
Earth’s water budget
all water on earth (70% of earth’s surface)
97% contained in oceans as salt water
3% freshwater
Hydrological cycle
the process where water is constantly recycled between the sea, air and land
Water borne
infection usually occurring from drinking contaminated water
Water washed
indirect infection, through skin, eyes or ears from exposure to contaminated water
Water based
pathogen spends part of life cycle in water. Route of entry into human water
Water related insect vector
spread by insects that breed in or near water
Ground water contamination
run-off/earth causes contaminated of groundwater
Water stress
when demand exceeds the available supply over a certain time period or when the quality of water restricts its use
Water scarcity
insufficient availability of quality water to meet the demands of a region’s population and ecosystems
Water as a resource
Filtration of un-clean water
Economic status - infrastructure to support
Population - is there enough to go around?
Climate - dry vs humid
Location - proximity & neighbouring
There but not usable
Agriculture grows
Water withdrawl
freshwater taken from ground or surface water sources either permanently or temporarily, and conveyed to a place of use
Water consumption
water use that is not returned to the original water source after being withdrawn
Water waste
water generated after the use of water in a variety of processes
Large scale scarcity (not enough)
building dams
rainwater harvesting
artificially recharged aquifers
Small scale scarcity
grey water recycling/nighttime watering
rainwater harvesting
drip irrigation
drought resistant crops
Degradation (not usable)
contamination groundwater (metals)
salinisation of top soil
pesticides/fertilisers
industrial pollutants
Soil systems
a dynamic ecosystem that has inputs outputs, storages and flows
Soil system storages
organic matter
nutrients
minerals
air
water
Soil
a mixture of eroded rock, mineral nutrients, decaying organic matter, water, air and billions of living organisms. it is continually changing and developing through physical, chemical and biological processes such as weathering, erosion and translocation
Why soil is important
grow crops/agriculture
habitat for organisms
trees (provide nutrients/root support)
filters water
Soil pyramid
Factors affecting soil characteristics
Climate: precipitation/evaporation balance determines the dominant direction of water movement.
Organisms: Soil organisms break down the dead organic matter and mix it into the upper layers of the soil.
Relief: The elevation of the land, the aspect of the slope (the direction it faces) and the angle of the slope
Parent material: The original material that the soil develops from. It will either be the bedrock (solid rock) or a drift deposit (lake or glacial) that has been laid down on top of the bedrock.
Time: Therefore the amount of time the soil has had to develop, will affect its characteristics natural capital’s ability to renew
Micro-organisms
bacteria, algae and fungi.
Macro-organisms
earthworms, insects, mites, millipedes and mammals, such as moles.
Soil ecosystem food web
Inputs of soil
minerals
organic matter
gases
water
Stores of soil
Organic matter
Organisms
Minerals
Air
Water
Nutrients
Outputs of soil
minerals
organic matter
water
gases
Sand
feel gritty, as the particles are quite big. The large particles create large pores spaces between them. This means that they are:
- Well drained so rarely get water logged.
- Subject to drought in times of low rainfall.
- Warm up quickly in summer due to high air content.
Clay
the smallest and give soil a sticky feel. Small particles give small pore spaces and are:
- Poorly drained and prone to water logging.
- Take a long time to dry out after rainfall.
- Warm up slowly in summer due to high water content.
Silt
too small for the human eye to see and soils high in silt have a smooth feel. The smaller particles give smaller pore spaces
EVS
Environmental value systems
What is the environmental value system
a worldview or paradigm that shapes the way an individual, or group of people, perceives and evaluates environmental issues
what are the categories of EVS?
ecocentrics, anthropocentrics, technocentrics
What is the ecocentric world view?
Puts ecology and nature as central to humanity, it is life-centered, respects the rights of nature and dependence of humans on nature
e.g. Bhutan’s ecocentric policies have led to high levels of biodiversity, pristine natural landscapes, and a strong commitment to environmental conservation. They prioritise the well-being of ecosystems alongside human development.
ecocentric categories
deep ecologists, self reliant soft ecologists
What is the anthropocentric world view?
Believes humans must sustainably manage the global system (through use of taxes, environmental regulation) and nature is there to benefit human kind.
e.g. The anthropocentric approach in the United States has contributed to significant economic growth and technological advancement. However, it has also led to various environmental challenges, including habitat destruction, pollution, and climate change. They struggle to balance the two
What is the technocentric world view?
Believes that technological developments can provide solutions to environmental problems.
e.g. Singapore’s technocentric approach led to significant advancements in sustainability, resource efficiency, and urban livability. Using technology and innovation, the country has effectively addressed its environmental constraints and created a model for sustainable urban development.
technocentric categories
technocentrics, cornucopians
environmental managers
believe humans have ethical duty to protect the earth
believe that governments need to protect environment, and make sustainable economies
deep ecologists
put more value on nature than humanity
believe in biorights - all societies and ecosystems have an inherent value and humans have no right to interfere
nurturing value system
ecocentric
intervening or manipulative systems
anthropocentric and technocentric
types of systems
closed system, open system, isolated system
closed system
exchanges energy but not matter and does not occur naturally on earth.
e.g. Earth is closed itself because it does not exchange significant amounts of matter with space.
what does the biosphere consist of?
atmosphere, lithosphere, hydrosphere, ecosphere
all systems have …
storages (of matter or enegry)
flows (into, through and out of the system)
inputs
outputs
boundaries
processes
Trans
when the flow of energy or matter flows and changes location but not its state
types of energy transformations
chemical to mechanical
radiant to chemical
electrical to thermal
Models
representation of a complex process, used to understand how a system works and to make predictions
advantages of models
easier to work with
can be used to predict the effect of a change of input
can be applied to other situations
patterns
visualization of smaller/larger things
disadvantages of models
accuracy is lost due to simplification
if assumptions are wrong, model will be wrong
predictions may be inaccurate
when is sustainability achieved?
environment, social and economic overlap
social factor (explain)
standard of living
education
community
equal opportunity
environmental factor (how to achieve sustainability)
natural resource use
environmental management
pollution prevention
economic factor (explain)
profit cost savings
economic growth
R and D
economic-social
business ethics
fair trade
workers rights
social-environmental
environmental justice
natural resources stewardship
local and global
environmental-economic
energy efficiency
subsidies/incentives for use of natural resources
Energy in systems rely on…
the laws of thermodynamics
First law of thermodynamics
energy can neither be created nor destroyed. The total amount of energy in an isolated system does not change but the energy may transform from one type to another.
Second law of thermodynamics
the entropy of a system increases over time; the only way to avoid entropy is a continuous input of additional energy.
entropy
spreading out or dispersal of energy
nature of equilibria
steady state equilibrium
static equilibrium
efficiency
defined as useful energy
efficiency formula (2)
efficiency = energy produced / energy consumed x 100%
efficiency = useful output / input x 100%
equilibrium
the tendency for a system to return to an original state following a disturbance
Static equilibrium characteristics
no change over time
stable
when disturbed, creates new equilibrium
non living systems
negative feedback
promotes stability in a system as it reverses the change and returns the system to the original state of equilibrium.
e.g.
positive feedback
amplifies the change in the system and keeps it going in the same direction. So a small disturbance in the system causes an increase in that disturbance.
e.g more CO2 in the atmosphere =
rising temperatures, which causes permafrost to melt. That releases methane and so temperatures continue to rise.
Note 
Flashcard (48)