Key terms from each chapter
TOPIC 1.1: FOUNDATIONS OF ESS
Ecocentric
Deep ecologists
Believe that all development must stop
Antropocentric
environmental managers
Believe that development is acceptable if it is controlled and moderated
Technocentric
cornucopians
Believe that human ingenuity and technology will save the day
TOPIC 1.2: SYSTEMS AND MODELS
System
a set of interrelated parts and the connection between them that unites them to form a complex whole and produces emergent properties
Inputs
identifies the elements that go into the system in order for there to be processes, outputs and feedback
inputs are flows that may be physical things such as water entering an ecosystem
eg: solar energy for photosynthesis
cultural behaviors entering environmental value systems
Processes
acts on the inputs and transform them into outputs
Outputs
the flows of matter and energy that leave the system
Open system
exchanges matter and energy with its surroundings
Closed system
exchanges energy but does not exchange matter with its surroundings
Isolated systems
exchanges neither energy nor matter with its surroundings
Transfers
moves energy or matter from one place to another without changing it in any way
eg: the food web moves matter through the living organisms in its links
Transformations
moves energy and matter but in the process of doing so, there is a change of state or form
eg: water changing its state from solid, to liquid, to gas (matter)
incoming light is transformed into heat as it is re-radiated from the earth’s surface (energy)
TOPIC 1.3: ENERGY AND EQUILIBRIA
First law of Thermodynamics
energy can neither be created nor destroyed
Entropy
the increase in disorder and randomness in a system
(terms of energy) an increase in entropy means a decline in the amount of energy available to do work
Second law of Thermodynamics
the entropy of a system increases over time; the only way to entropy is a continuous input of additional energy
Negative Feedback
the feedback type which promotes stability in a system as it reverses the change and returns the system to the original state of equilibrium
eg: predator-prey relationship
Positive Feedback
the feedback type which amplifies the change in the system and keeps it going in the same direction
Tipping Points
a part of a system that kick-starts self-perpetuating positive feedback loops that push the systems to a new state of equilibrium
Equilibria
if everything is in balance, the system is said to be in equilibrium
Steady State Equilibrium
has many small changes over shorter periods of time and the changes occur within limits
Stability
the ability of an ecosystem to remain in balance
Resistance
where the ecosystem continues to function during a disturbance
Resilience
the ability of the ecosystem to recover after a disturbance
TOPIC 1.4: SUSTAINABILITY
Natural resources
classified according to how long they take to be replaced and they range from non-renewable to renewable
Natural Capital
the natural resource that can be used for the long-term supply of goods and services
Goods
marketable commodities that can be exploited by humans
Services
natural processes that provide benefits for humans such as water replenishments, clean air and protection against erosion
Natural Income
the yield from natural capital
Sustainability
the management of the exploitation of resources that allows for replacement of the resources and full recovery of the ecosystems that may be affected by extraction
Ecological Footprint (EF)
the amount of land and water that is required to support a human population at a given standard of living — providing all the resources and assimilating all the waste
Environmental Impact Assessment (EIA)
the process of identifying, predicting, evaluating and mitigating the biophysical, social, and other relevant effects of development proposals prior to major decisions being taken and commitments made
it is also a formal process that is put into action before something major can be changed
TOPIC 1.5: HUMANS AND POLLUTION
Pollution
the addition to substances into the natural environment at a rate that is greater than that at which they can be rendered harmless and which causes adverse changes
Point-source Pollution
a single identifiable source of pollution
eg: discharge from a wastewater treatment plant
Non-point source Pollution
pollution from diffuse sources, often difficult to monitor
Air Pollution
the introduction of harmful materials into the atmosphere
Water Pollution
generally occurs when pollutants are introduced into a body of water without having harmful substances removed
Land Pollution
the result of human misuse of land resources. it is often caused by poor disposal of waste, use of chemicals such as insecticide, pesticides and fertilizers for agriculture that wash into the soil and damage it
Light Pollution
one of the less-considered types of pollution, which is caused by poor use of lighting in towns and cities
Noise pollution
the presence of loud sounds that can be harmful or annoying
Thermal pollution
changes the temperature in an area, usually with a rise in temperature of water or air
DDT
(dichlorodiphenyltrichloroethane) is an oganochloride insecticide that is colorless, tasteless, and odorless
it was first synthesized in 1874 and used as an insecticide in 1939
DDT is considered a Persistent Organic Pollutant (POP)
TOPIC 2.1: SPECIES AND POPULATIONS
Biotic components
the biotic element of the ecosystem is anything that is living and any interactions between the living components. that includes all the organisms, anything that they consume or that consumes them and human influences
Producers
plants that convert energy into matter
Consumers
animals that eat plants or other animals
Decomposers
organisms that breakdown waste into component parts for reuse
Species
a group of organisms with common characteristics that can interbreed to produce fertile offsprings
Population
a group of individuals of the same species living in the same area at the same time
Abiotic components
the biotic elements of the ecosystem interact with the abiotic elements - the non-living things
abiotic factors include: temperature, sunlight, pH, alinity, and precipitation
Temperature
an important abiotic factor in all ecosystems, as it varies seasonally and dirunally
Sunlight
is the base of the vast majority of food chains on earth
solar energy makes photosynthesis possible and enables plants to transform light energy into chemical energy
Water
an essential to all life on earth and can arrive in an ecosystem as precipitation, groundwater flow or overland flow
Habitat
the environment in which a species usually lives
Niche
the role an organism plays and the position it holds in the environment
it includes all the interactions the organism has with the abiotic and biotic environment
Limiting factors
the resources in the environment that limit the growth, abundance and distribution of organisms/populations in an ecosystem
Density dependent factors
factors that affect the population only when it reaches a certain density
Density independent factors
factors that will control populations, no matter what the density of it is
Carrying capacity
the maximum number of individuals of a species that the environment can sustainably support in a given area
J-shaped growth curve
a curve which shows exponential population under ideal conditions with plenty of resources and limited competition
the population continues to grow until environmental resistance take effect
S-shaped curves
exponential growth is only possible for a short period of time because as the population grows, resources are depleted and the growth rate slows and will eventually plateau off
Predation
where one organism (the predator) hunts and kills another (the prey) in order to provide it with the energy for survival and reproduction
Herbivory
the consumption of plant material by an animal
Parasitism
when an organism (the parasite) takes nutrients from another organism (the host)
Mutualism
where two organisms of different species exist in a mutually beneficial relationship
Competition
where organisms compete for a resource that is in limited supply
Intraspecific competition
occurs when members of the same species compete for a limited resource
Interspecific competition
where members of different species compete for a resource that they both need
TOPIC 2.2: COMMUNITIES AND ECOSYSTEMS
Ecosystem
a community of interdependent organisms and the physical environment they interact with
Community
a group of populations living and interacting with each other in a common habitat
Decomposers
absorbs and metabolize waste and dead matter on a molecular level then release it as inorganic chemicals that can be recycled through the ecosystem via plants
Respiration
animals eat plants (or other animals) the process of photosynthesis is reversed in respiration
Trophic level
the position an organism (or group of organisms in a community) occupies in the food chain
Bioaccumulation
the increase in the concentration of a pollutant in an organism as it absorbs or it ingests it from its environment
Biomagnification
the increase in the concentration of the pollutant as it moves up through the food chain
TOPIC 2.3: FLOWS OF ENERGY AND MATTER
Absorption
where light energy is retained by the substance and transformed into heat
Gross Primary Productivity (GPP)
all the biomass produced by primary producers in a given amount of time
Net Primary Productivity (NPP)
NPP takes into account respiratory losses (R)
Gross Secondary Productivity (GSP)
represents the total amount of energy or biomass assimilated by consumers
Sustainability Yield (SY)
the amount of biomass that can be extracted without reducing natural capital of the ecosystem
TOPIC 2.4: BIOMES, ZONATION AND SUCCESSION
Hadley cell
the cent of the thermal equator (point of greatest heating)
Topography
the shape of the land, mountains, altitude and aspect
Aspect
the direction in which the slop face, so it has a very localized impact on climate
Biome
a collection of ecosystems that are classified according to their predominant vegetation
they share similar climatic conditions and organisms that have adaptations to the environment
K-strategists
produce very few offsprings but they increase the quality of them by investing in a lot of parental care
r-strategists
focuses on the increased quantity of offspring at the expense of quality, with little to no parental care, survival chances are low but high numbers of offspring ensures at least some will survive
Type I survivorship curve
indicates K-selected species
the curve starts out very flat, showing a high survival rate in early life. This long life expectance causes the line to have a sharp drop at the end, as the mortality increases dramatically
Type II survivorship curve
shows the middle ground with a more or less constant mortality rate throughout the organisms life
Type III survivorship curve
this is typical of r-selected species
the curve drops sharply immediately showing very low survival rates after birth
Succession
the predictable change over time
Zonation
a spatial change in response to changing conditions
Colonization
initiated by pioneer species that are adapted to the extreme conditions
Establishment
it follows colonization. In this stage, the ecosystem is just getting going as an ecosystem, as opposed to a collection of constituent part
Competition
throughout succession each species is adapted to a very specific set of abiotic conditions — the pioneer species thrive in the harsh conditions of the early stages of succession
Climax community
the steady state of equilibrium with the climate and/or soil. the succession has come as far as it can and will be self-perpetuating as long as prevailing climatic conditions
TOPIC 2.5: INVESTIGATING ECOSYSTEMS
Random sampling
every item has the same chance of being selected through the use of random numbers
Systematic sampling
where samples are chosen in a regular way (or with an nth term)
Stratified sampling
when the population is known to contain subsets. it is important to know the size of the subsets in the whole population so that your sample reflects the same proportions
Quadrats
an appropriately shaped plot used to identify the area you wish to study
Motile organisms
motile animals are the ones that are mobile (that can move)
TOPIC 3.1: AN INTRODUCTION TO BIODIVERSITY
Biodiversity
the variety of all life on earth. It includes genetic diversity, species diversity and habitat diversity
Species diversity
the number of different species in a given area, taking into account the richness and evenness of the species
Genetic diversity
refers to the variation of genes within the genetic pool of a population of a species; it is the means by which that population can adapt to change
Habitat diversity
the range of different habitants in the same area
TOPIC 3.2: ORGINS OF BIODIVERSITY
Evolution
the idea that if you take any two creatures on earth and trace their ancestry back far enough, you will find a common ancestor
Mutations
a change in the DNA and it can be a single change or multiple changes. Evolution is usually the result of an accumulation of several mutations
Natural selection
the gene variation has survival advantages
Artificial selection
human- created selections
Convergent evolution
where similar structures have evolved independently in different organisms without the presence of a common ancestor, such as the sperm whale and copepods, have both evolved the same buoyancy control but they are unrelated
Vestigial structures
these are parts of an animal that no longer serve any purpose but they serve as reminders of what the organism evolved from
Speciation
the formation of a new species through biological processes
Survival of the fittest
a concept that encompasses the most important aspects of natural selection: survival and reproductive success
Endemic species
unique to a particular location and not found elsewhere
Mass extinction
a sudden global decrease in the number of species over a relatively short period of time
Background or normal extinction
the standard rate at which species go extinct
TOPIC 3.3: THREATS TO BIODIVERSITY
IUCN Red List
International Union for Conservation of Nature Red list
aims to provide information and analysis on the status, trends and threats to species in order to inform and catalyze for biodiversity conservation
Biological Hotspots
two key elements to the concept are that these sites must have a high level of endemic species and also be under threat
TOPIC 3.4: CONSERVATION OF BIODIVERSITY
Environmental Value Systems (EVS)
a system in the sense that it has inputs (education, culture, religion, media), and outputs (decisions, perspectives, courses of action) are determined by processing these inputs
Utilitarian value
where there is an economic value associated with the use of resources
Non-utilitarian value
when use does not have any economic values
The Millennium Ecosystem Assessment
a report that categorized the values of biodiversity into the following groups: provision value (freshwater, food etc), regulating value (climate, flood etc), supporting values (nutrient cycling, soil formation, primary production, etc), and cultural values )aesthetic, spiritual, educational and recreational uses)
Non-Governmental Organizations (NGOs)
non-profit, voluntary organizations usually funded by charitable donations and membership fees
Intergovernmental Organizations (IGOs)
consist of members from different countries. They are funded by its members, such as the UN
Convention on International Trade in Endangered Species (CITES)
aims to ensure that international trade does not threaten survival of the species
Umbrella species
often large species requiring large habitat areas. Protecting the habitat of this species also protects the habits of other species
Keystone species
these species interact through the food web with other species in the community and if lost could lead to the demise of other species
In-situ conservation
protection of species in their habitat
Ex-situ conservation
improve the probability of survival of the species by taking them out of their habitat
TOPIC 4.1: INTRODUCTION TO WATER SYSTEMS
Hydrological cycle
used to describe the movement of water on the planet
Flows
the flows can be categorized as either transformations or transfers
Global conveyor belt
also called the “thermohaline circulation” is driven by differences in water density, dependent on temperature and salinity of water
TOPIC 4.2: ACCESS TO FRESH WATER
Water stress
when demand exceeds the available supply over a certain time period or when the quality of water restricts its use
Reservoirs
can be either natural or artificially created lakes, used to collect and store water
Artificial recharge
used to increase the amount of water stored in aquifers
TOPIC 4.3: AQUATIC FOOD PRODUCTION SYSTEMS
Aquatic ecosystem
a body of water which can be either marine or freshwater
Capture fisheries
harvesting aquatic organisms from their natural environments without artificial intervention
Aquaculture
the farming of aquatic organisms
TOPIC 4.4: WATER POLLUTION
Domestic sewage
a mainly organic waste, consisting of carbohydrates, proteins, fats, ammonium compounds, as well as soaps, synthetic detergents and dissolved salts
Industrial discharge
usually varies in composition depending on the on-site processes and materials used
Organic waste
waste that is biodegradable and is food source for micro-organisms naturally found in the environment
Synthetic compounds
man-made compounds that only have been prevalent since the 1940s
pH
pH often reflects the local geology and soil
Suspended solids
small particles that can block sunlight penetrating through the water, reducing photosynthesis
Biochemical Oxygen Demand (BOD)
the measure of the amount of dissolved oxygen used to breakdown the organic material in a given volume of water through aerobic activity
Indicator species
biological monitoring method which uses organisms which can indicate whether the water quality has declined and whether there have been episodes of pollution between periods of sampling
Biotic index
used to determine water quality using aquatic organisms
Eutrophication
often caused by domestic or industrial effluent discharges and run-off from farms
TOPIC 5.1: INTRODUCTION TO SOIL SYSTEMS
Soil
a mixture of 4 basic parts — minerals, organic matter, air and water. It is a medium for plant growth. Soil supplies the plants with nutrients and water and a place for them to anchor
Minerals
the minerals of a soil come from the weathering of the parent material. Weathering is the breakdown of the parent material by physical, chemical and biological processes
Organic matter
organic matter comes from the organisms that are on and in the soil
Gases
certain plants fix atmospheric nitrogen and change it into nitrates and ammonia compounds in the soil
The Organic horizon (O horizon)
the top of the soil and includes all the DOM that accumulates on the top of the soil
The A horizon
known as the mineral layer. This layer is usually dark in color due to the high proportion of organic matter
The B horizon
known as the sub-soil and tends to be the zone of illuviation or accumulation
The C horizon
the decomposed parent material
TOPIC 5.2: TERRESTRIAL FOOD PRODUCTION SYSTEMS AND FOOD CHOICES
Organic farming
prohibits the use of genetically modified organisms (GMOs), chemical fertilizers and restricts the use of chemical pesticides
Intensive subsistence farming
this type of farming tends to be widespread in many parts of Asia
TOPIC 5.3: SOIL DEGRADATION AND CONSERVATION
Erosion
erosion typically removes the fertile topsoil. The loss of organic matter also leads to a reduction in water retention capacity
TOPIC 6.1: INTRODUCTION TO THE ATMOSPHERE
Troposphere
this is the layer closest to the earth’s surface and includes where we live. It extends up to about 10km above sea level
Greenhouse effect
when energy from the sun enters the earth’s atmosphere as short wave radiation, some of it is absorbed by the earth’s surface. As the ground warms, heat energy is radiated back into the atmosphere in the form of long wave radiation
Stratosphere
this layer extends from 10 to 50km above sea level and is where the stratospheric ozone absorbs UV radiation from the sun. Temperature is constant at about -60℃ in the lower part of the stratosphere, which is shielded by the ozone layer but then increases with altitude
Mesosphere
this layer ranges from 50 to 80km and is where without the presence of ozone or other particulates to absorb UV radiation, the temperature declines with height
Thermosphere
this layer extends beyond about 80km to between 500km and 1,000km. Within the thermosphere: UV and X-radiation from the sun is absorbed which breaks apart molecules into atoms
TOPIC 6.2: STRATOSPHERIC OZONE
Ozone
is formed by sunlight energy breaking the bonds within diatomic oxygen molecules to form atomic oxygen which in turn reacts with oxygen molecules to form ozone
Chloroflurocarbons (CFCs)
are very stable compounds. They were initially considered to be non-problematic to the environment due to their high stability
Montreal Protocol (1987)
targets set on production and consumption of ODS are legally binding
it sets out a timetable to reduce production of CFCs by 50% and freeze production of halons
TOPIC 6.3: PHOTOCHEMICAL SMOG
Particulates
produced during combustion of fossil fuel and emitted into the atmosphere. Suspended particulates such as smoke and soot are often categorized according to size
PM10
particulate matter with a diameter of 10µm or less. Exposure to PM10 has also been associated with an increased risk of cardiovascular disease
PM2.5
particulate matter with a diameter of 2.5µm or less. PM2.5 which can travel deep into the lungs, increasing the risk of respiratory diseases and cancer
Photochemical smog
photochemical smog occurs when sunlight activates reations between nitrogen oxides (NOx) and volatile organic compounds (VOCs), resulting in the formation of ozone and peroxyacyl nitrates (PAN)
TOPIC 6.4: ACID DEPOSITION
Wet deposition
when pollutants are incorporated into the clouds or falaling raindrops and result in acidified rain or snow
Dry deposition
when atmospheric pollutants are removed by gravity or direct contact under dry conditions
TOPIC 7.1: ENERGY CHOICES AND SECURITY
Fossil fuels
formed from dead plants and animals under pressure over millions of years. They provide a finite source of energy and if use continues they were eventually become exhausted
Hydropower
the energy obtained from the movement of water has historically been used to drive a variety of machinery from grinding flour and sawing wood
Energy security
the uninterrupted availability of energy sources at an affordable price
TOPIC 7.2: CLIMATE CHANGE — CAUSES AND IMPACTS
Climate
the “average'“ weather over the long term (eg. years) often at a regional level
Weather
refers to the conditions over a short time scale (eg. day to day) at a local level. Changes in weather over time are presented as statistics
Tricellular model
a model used to explain transfer of heat through the atmosphere
Hadley cell
as air is heated at the equator, it rises and cools with altitude which stops it rising further. As the air moves towards the pole, it is deflected towards the right in the northern hemisphere and towards the left in the southern hemisphere
Farrel cell
as the air moves from the Hadley cell towards the pole, it enters the Ferrel cell where it picks up moisture as it crosses the sea
Polar cell
air that moves from the Ferrel cell to the Polar cell, rises and continues moving towards the pole. As the air cools it descends, creating a high pressure region and some of the air moves back towards the equator forming the polar fronts that meet the Ferrel cell
El Niño
where one part of the world influences the weather and climate in another area
Ice albedo
when a white and reflective surface starts to melt, it reduces the amount of solar radiation that is reflected back into space. Dark surfaces which replace the ice and snow increase absorption of sunlight and contribute to global warming
Tipping point
a level of change in system properties beyond which a system reorganizes, often abruptly, and doesn’t return to the initial state even if the drivers of the change are abated
TOPIC 7.3: CLIMATE CHANGE — MITIGATION AND ADAPTION
Mitigation
a human intervention to reduce the sources or enhance the sinks of greenhouse gases (GHGs)
Adaption
the process of adjustment to actual or expected climate and its effects. In human systems, adaption seeks to moderate or avoid harm or exploit beneficial opportunities
Intergovernmental Panel on Climate Change (IPCC)
set up by the United Nations Environmental Program (UNEP) and World Meteorological Organization (WMO) in 1988. The aim of the IPCC is to provide a scientific view of the current knowledge and understanding of climate change and its impacts
United Nations Framework Convention on Climate Change (UNFCCC)
it came to force in 1994 with the aim of stabilizing atmospheric greenhouse gas levels by providing a framework fro protocol agreements
TOPIC 8.1: HUMAN POPULATION DYNAMICS
Crude Birth Rate (CBR)
the number of births/1000/year
formula: CBR = number of births/total population x1000
Total Fertility Rate (TFR)
the number of children a woman is expected to have in her lifetime
Infant Mortality Rate (IMR)
IMR is the number of babies that die in their first year of life/1000 live births/year
Crude Death Rate (CDR)
the number of deaths/1000/year
formula: CDR = number of death/total population x1000
Natural Increase Rate (NIR)
the combination of fertility and mortality to determine population size
formula: NIR = (CBR-CDR)/10
Population pyramids
known as “age-sex pyramids” or “age-gender pyramids”. they are a graphical illustration to show the age and gender distribution of a population
Stage 1 of population pyramid: Pre-industrial society
it shows concave sides to the pyramid and a very large drop in numbers between 0-5 and 6-10 year age groups. This indicates high mortality rates, especially child mortality
Stage 2 of population pyramids: Urbanizing/industrializing
a pyramid with straighter sides means low mortality between age groups and a population that will be expanding rapidly
Stage 3 of population pyramids: Industrial
pyramids with a narrower bas indicates a falling birth rate
Stage 4 of population pyramids: Post industrial
by this stage birth rates, death rates and NIR are all low. However the population is already large having gone through a period of high growth
Stage 5 of population pyramids: Post industrial
death rates now exceed birth rates due to an increase in the so-called lifestyle diseases, such as low exercise and high levels of obesity causing cardiovascular diseases
Demographic transition models (DTM)
was developed in the 1920s and was based on the observation of the demographic changes in selected countries over the previous 200 years
TOPIC 8.2: RESOURCE USE IN SOCIETY
Economic natural capital
something tangible that has monetary value
Living natural capital
something that must be managed carefully and used sustainably
Non-living natural capital
renewable in a way that we cannot change (such as wind, tidal, solar etc)
TOPIC 8.3: SOLID DOMESTIC WASTE
Non-biodegradable waste
anything that will not breakdown into simple components
Landfill sites
a hole in the ground where waste materials are buried
Incineration
a waste treatment process that involves the combustion of waste. Initially incineration was simply burning trash in a hole in the ground
Recycling
to recycle something the original product is transformed into a new raw material that can be used for another product
Composting
the act of piling up organic material and leaving it until the next growing season
TOPIC 8.4: HUMAN POPULATION AND CARRYING CAPACITY
Biocapacity
the biological capacity of an area/region/country to generate the resources and absorb the wastes of a given population
Agenda 21
where 178 governments voted to adopt the this program. it is a UN initiative for multilateral organizations, and governments to be executed at local, national and global levels