energy & environment management€¦ · 99% of the gases are found in the troposphere and...
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What is Sustainable Development?“sustainable development is development that meets thesustainable development is development that meets theneeds of the present without compromising the ability offuture generations to meet their own needs.”g( Brundtland Commission of the United Nations on March 20, 1987: )
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Principles of SD:p Futurity‐inter‐generational equityS i l j ti i t ti l it Social justice‐intra‐generational equity
Transfrontier responsibility‐ geographical equity Procedural equity‐people treated openly and fairly Inter‐species equity‐importance of biodiversity Inter‐species equity‐importance of biodiversity
Environment The environment is everything that surrounds you; the air, the
land, the oceans, and all living things.
The natural environment is subdivided into two parts: the physical environment and the biological environment (biosphere).
The physical environment is divided into three spheres on the basis of states of matter:of states of matter:
The lithosphere (solid)The hydrosphere liquid)The atmosphere (gas)
Earth’s Atmosphere Earth’s atmosphere is divided
into layers on the basis of changing temperature gradients.changing temperature gradients.
The density of atmospheric gases decrease exponentially g p ygoing away from the earth’s surface.
99% of the gases are found in the troposphere and stratosphere.
Hierarchy of Biosphere Organisms, composed of atoms, molecules, and cells,
d i l iare grouped into populations.
Populations form pcommunities, which then form ecosystems.
Ecosystems comprise the biosphere, which includes all lif E thlife on Earth.
E lEcology The science of ecology examines how The science of ecology examines how organisms interact with each other and with the physical environmentthe physical environment.
Ecological principles have great value in Ecological principles have great value in assessing how humans are disturbing biological systems and in finding ways tobiological systems and in finding ways to minimize this disruption.
Biosphere Interactions: Populations A population is a group of organisms of the same species living in the same area.
All populations undergo three distinct phases during their existence:phases during their existence: Growth
S bili Stability Decline
Population GrowthPopulation Growth
Bi th t d th t d th Birth rates, death rates, and the age structure affect its growth rate.
Population Stability Population growth is eventually limited by a complex interaction
of many factors, including other species.
Carrying capacity is the maximum population that can be sustained by an environment for a long time.
Factors which limit the rates of reproduction and survival occur in both the physical and biological environment: Physical limitationsy Symbiosis Predation Competition Competition
Complex Interaction of AbundanceComplex Interaction of Abundance Controls
Most natural populations are governed by several l f i i l lcontrols, often acting simultaneously.
The addition of a third species a parasite The addition of a third species, a parasite, changes the success of two competing populations.
Natural communities are composed of populations of hundreds or thousands of species
Human Impact on Population Size Humans may cause population growth by removing previous limitations or population decline by imposingprevious limitations or population decline by imposing new limitations.
Humans cause population increases by: An increase in available resources Competitive release Predator release
I d i Introduction to new areas
Human Impact on Population Size Humans cause population decreases by Humans cause population decreases by
Habitat disruption Introduction of new species Overkill Overkill Secondary
extinctions
S i I t d tiSpecies Introduction The introduction of nonnative (“exotic”) The introduction of nonnative ( exotic ) species may be the single greatest alteration of nature humans have carried out yet.
O h i i bli h d Once the organism is established, population and range expansion can be quite rapid.
Ecological Succession Succession is the sequential replacement of species in a community
by immigration of new species and local extinction of old ones.
Pi i l i i d b di b Th Pioneer species colonize a site opened by disturbance. These populations are replaced by intermediate species, which are eventually replaced by a climax community.
Succession occurs because each community, pioneer to climax, prepares the way for the stage that follows by altering environmental traits.
Succession is characterized by several trends: Decreasing productivity Increasing diversityIncreasing diversity Increasing biomass
Ecosystem and Community Function Communities vary in structure but are alike in that they all carry out
basic processes.
The most basic processes are: Energy flow Matter cycling Matter cycling
All organisms eat to stay alive, causing energy and matter to move through the community.through the community.
All energy and matter ultimately come from, and return to, the physical environment.physical environment.
Food Web
Energy flows are routed through feeding l i hi i hrelationships in the ecosystem.
A f d b d ib h l A food web describes the complex interrelationships by which organisms consume other organismsother organisms.
Biomass Pyramids Biomass is the weight of living
matter.
The first trophic (feeding) level is the producers, which capture energy p , p gyfrom the non‐living environment.
Consumers derive energy from the Consumers derive energy from the chemical energy stored in the bodies of producers or other consumers.