Chapter 1 Environmental Problems Their Causes and Week 1 Sustainability Section 1 1 1 Sustainability Capacity of the earth s natural systems and human cultural systems to survive flourish and adapt to changing environmental conditions into the very long term future 2 Environment All external conditions and factors living and nonliving chemicals and energy that affect an organism or other specified system during its lifetime 3 Environmental Science an interdisciplinary study that uses information from the physical sciences and social sciences tolerant how the earth works how we interact with the earth and how to deal with environmental problems 4 Ecology Study of the interactions of living organisms with one another and with their nonliving environment of matter and energy study of the structure and functions of nature 5 Environmentalism A social movement dedicated to protecting the earth s life support systems for us and other species 6 Three scientific principles of sustainability derived from how the natural world works are a Dependence on solar energy b Biodiversity c Chemical cycling 7 Solar Energy Direct radiant energy from the sun and a number of indirect forms of energy produced by the direct input Principal indirect forms of solar energy include wind falling and flowing water hydropower and biomass solar energy converted into chemical energy stored in the chemical bonds of organic compounds in trees and other plants 8 Biodiversity Variety of different species species diversity genetic variability among individuals within each species genetic diversity variety of ecosystems ecological diversity and functions such as energy flow and matter cycling needed for the survival of species and biological communities functional diversity 9 Chemical Cycling Circulation of chemicals necessary for life from the environment mostly from soil and water through organisms and back to the environment Natural Capital includes natural resources such as air water soil wildlife minerals etc and ecological services Natural Resources The earth s natural materials and processes that sustain life on the earth and our economies Examples of natural capital o Natural pest control processes o Forests o Recycling Exponential growth is a concept that we use to study human population Environmental scientists are concerned about economic growth because economic growth can lead to higher levels of resource use Developed nations make up about 20 of the world population but use about 88 of the Nonrenewable resources are fixed in quantity Another way of describing the tragedy of commons is overuse of common property or resources free resources Ecological footprint the amount of land needed to produce the resources used by the average person in a country If you live in a developed country your ecological footprint is likely to be larger than the ecological footprint of a person from a developing country Fertile soil is an example of a renewable resource Pollution any addition to air water or soil that harms humans or other organisms Population and Per capita resource use are intertwined when evaluating the impact of a country on the environment The level of technological development of a country affects the environmental impact of that population Sustainable economic development can be defined as penalizing polluters and resource wasters and providing subsidies and rewards for environmentally friendly businesses Chapter 2 Only systems portion A System is a set of components that function and interact in some regular way o Can become unsustainable if the throughputs of matter and energy resources exceed the abilities of the systems environment to provide the required resource inputs and to absorb or dilute the systems outputs of matter and energy Most systems have the following key components o Inputs of matter and energy from the environment o Flows or Throughputs of matter and energy within the system o Outputs of matter and energy to the environment Feedback Loop occurs when an output of matter energy or information is fed back into the system as an input and leads to changes in that system Positive Feedback Loop Causes a system to change further in the same direction o Ex decreasing vegetation in a valley causes increasing erosion and nutrient losses that in turn cause more vegetation to die resulting in more erosion and nutrient losses Negative Feedback Loop Causes a system to change in the opposite direction from with it is moving o Ex A thermostat a device that controls how often and how long a heating or cooling system runs o Ex recycling and reuse of some resources such as aluminum Time Delay lack of response during a period of time between the input of a feedback stimulus and the systems response to it o Can allow an environmental problem to build slowly until it reaches a threshold level or tipping point o Tipping Point point at which a fundamental shift in the behavior of a system occurs System Effects Synergy o Synergistic interaction or synergy Occurs when two or more processes interact so that the combined effect is greater than the sum of their separate effects Ex scientific studies reveal such an interaction between smoking and inhaling asbestos particles Nonsmokers are exposed to asbestos particles for long periods of time increase their risk of getting lung cancer fivefold But people who smoke have 50 times the risk that nonsmokers have of getting lung cancer WEEK 2 Chapter 4 Biodiversity and Evolution Four components of Biodiversity o Functional o Genetic o Ecological o Species Biological evolution has been going on for about 3 7 billion years The theory of evolution states that all species have descended from earlier ancestral species In a population individuals may have different forms of the same gene Mutation genetic variability occurs through random changes in the structure or number of DNA molecules in a cell Natural selection is more likely to occur when there is a change in environmental conditions Coevolution occurs when populations of two different species who have interacted over a long period of time develop genetic changes that reflect their relationship with the other species A species functional role in a community or ecosystem is its niche Specialist species o May be able to live in only one type of habitat o Limited in the climates they can tolerate o More prone to extinction than generalist species The most common method of speciation is called allopatric speciation Major