Midterm 1 Flashcards
Negative Feedback
A feedback resulting in stability by decreasing disturbance. ex. increase in herbivores–> increase in carnivores –> decrease in herbivores
Positive Feedback
Amplification of an effect by it’s own influence resulting in exponential growth. ex. Unregulated deer population –> increases until the vegetation cannot maintain it.
The three components of the human-environment interaction model
- Population (Size, distribution, density, growth rate)
- Resources (Natural: supply, character; and human: demand, extraction, use).
- Environmental change (biotic and abiotic)
The 5 factors influencing the interactions between population, resources and environment.
- Per capita consumption
- Public Policy
- Technology
- Culture/ Religion
- Externalities (i.e. the cost of production not included in the market price)
Definition: Externalities
the environmental cost of producing or using an economic good or service which is not included in the market price of the good or service. Ex. the greenhouse gases produced by labourers driving to work every morning to work in a factory
Definition: Common Property Resources
Resources which are free and accessible to all (ex. atmosphere, oxygen, water from the great lakes).
These resources are most commonly impacted by externalities.
Anthropocentric definition of a resource
The definition of a resource is defined based on the needs and demands of humans. i.e. a value judgement, culturally defined.
What we see as a resource is based on S.T.E.P
S.T.E.P Stands for….
Scientific knowledge, Technological knowledge, Economical knowledge and Political knowledge.
STEP is used in making value judgements of what a resource is.
Biocentric definition of a resource
Assumes the rights of non-human resources supersede human wants or needs. ex. an old growth forest has more value as an ecosystem than it has for logging.
Technocentric viewpoint
value system that is focused on technology and believe that human knowledge can surmount any problems that humans create. i.e. cornucopians
Ecocentric viewpoint
the belief that humans are part of the biosphere are so subject to it’s laws rather than our own. These people believe we should switch from managing ecosystems to the benefit of humans to controlling humans for the benefit of ecosystems.
Four characteristics of functional resources
- Resources are dynamic not static: i.e. the value of resources is changing. (ex. wood 500 years ago to now)
- Resources may be depleted (ex. fossil fuels), degraded (ex. pollution of water) and/or made obsolete (ex. extinction).
- Resources can be extended (or made to last longer) through technology and management: ex. recycling
- Resources can be hazards (ex. property on water= worth more, and more exposed to hazards such as erosion).
Definition: Flow Resource
can be depleted, sustained or increased on the basis of management. Ex. soils, forests, wildlife, fish, water, etc
Definition: Stock Resource
Physically exhaustible and may (ex. metal) or may not (ex. coal, oil, uranium, natural gas) be capable of reuse
Definition: Continuous Resource
Availability is endless and may be independent (Ex. solar energy, tidal energy) or affected by (ex. air and ocean quality) human action.
Definition: Environmental Sustainability
Maintaining or restoring the quantity or quality of biophysical resources upon which humans depend
Assessing environmental sustainability: Input Rule (two parts)
a. The harvest or consumption of renewable resources should be within the regenerative capacity of nature.
b. The depletion rates of non-renewable resources should be equal or less than the rate we develop renewable substitutes.
Assessing environmental sustainability: Output Rule
The emissions that we release into the environment must be within the assimilative capacity of the environment into which the emissions are released.
What is an environmental impact? What are the challenges with its definition?
The definition of environmental impact reflects a “value judgement” based on human demands (i.e. depends on our personal STEP).
Management is very difficult if we have no agreement on what is valuable and thus what needs to be protected.
Four types of environmental impacts: Change in…
Four types of environmental impacts are:
- Change in the quality of the biophysical environment.
- Change in biodiversity.
- Changing the supply/storage of resources.
- Changes in physical structure of the environment; ex. changing wetlands into agricultural land
Three types of problem displacement and examples of each
- Spatial Displacement: shipping waste away; building taller smoke stacks
- Displacement to another medium: i.e. incinerating waste –> reduces volume but contaminates air.
- Temporal displacement: leaving problem for future generations; ex. burying waste.
On what three items have we surpassed the boundaries of sustainability?
- Nitrogen: The release of nitrogen to the environment is much higher than can be sustained
- Climate change
- Biodiversity loss.
Lower Paleolithic/ Early Stone Age (>10,000 YBP)
- scavengers and hunters of wild animals
- opportunistic gatherers
- ate mainly meat
- highly mobile
Upper Paleolithic (~8,500-10,000 YBP)
-planted and harvested wheat and rice
sophisticated hunters and gatherers.
-mobile
-use of fire
Neolithic / Late Stone Age (~5,000-8,500 YBP)
- domesticated plants and animals
- permanent settlements
- food processing
- trade
Bronze age (<5,000 YBP)
- intensification of agriculture
- less reliance on hunting and gathering
- more and larger settlements
- metal
- sophisticated trade
Impact of fire on the environment:
Humans burned habitats to allow more areas for herbivores to graze. In New Zealanc, this was done to allow more habitat for Bracken fern.
Defintion: Pleistocene Overkill
A time period 12,000 years ago where human impact resulted in the demise of the megafauna (herbivores more than 50kg). On every continent, the megafauna went extinct promptly after the arrival of humans.
Definition: Domestication
- the controlling of the genetics of a plant or animal population by the planned selection of plant seeds and animals’ parents.
- the process by which plant and animal species come to depend on humans for survival while, in turn, providing humans with practical or other benefits
Definition: Pastoral Nomadism
This involves the rotational grazing of herbivores.
Can be completely sustainable. May not be sustainable when
- herd sizes are increased; or when
-there is natural variability of resources in a resource-limited environment and it cannot support the herd from year to year.
Definition: Shifting Cultivation
This involves crops as opposed to animals and occurs in moist environments such as rainforests. This involves clearing forest and planting crops for 2-3 years before moving on and clearing a new space. Farmers wouldn’t return to the original plot for 30-60 years, allowing the forest to regenerate.
-theoretically sustainable
Definition: Subsistence Farming
farming to provide food primarily for the farmer’s immediate family; a traditional form of farming; “farming for survival using human and animal effort”.
Definition: Industrial Farming
farming for the purpose of selling crops, animals, and related products; often specialized around selected crops or livestock (i.e. soybeans, cattle etc.). “Farming for profit, using whatever it takes”.
Industrial Revolution (1700-1900)
Coal became the main source of energy, resulting in smog days and loss of agricultural land to coal extraction.
Modern Industrial Society is characterized by four items:
- Increased production and consumption (because of advertising)
- Increased dependence on non-renewables
- shift from natural to synthetic/ technological
- increase in the amount of energy per unit output.
Two benefits of modern industrial society are:
- People are living longer due to environmental improvements
- Higher food production per capita.
Three Strategies to make modern industrial society more sustainable:
- Set environmental goals, standards and laws
- Accounting for externalities (i.e. paying the environmental cost when we buy products).
- Dealing with chemicals and hazardous waste (i.e. reducing the use of pesticides).
What are the three physical spheres?
- Atmosphere
- Hydrosphere
- Lithosphere
What three factors contributed to the creation of the earths environment?
- The earths position in the solar system (relative to the sun)
- Abundant water
- Oxygen rich
Definition: Kinetic Energy
i.e. wind
Definition: Latent Energy
involved of the change of state of water. i.e. evapotranspiration
Definition: Chemical energy
i.e. photosynthesis