Ecosystem Energy Flow & Productivity

• Photosynthesis formula: 6CO2 + 6H2O + Light energy -> C6H12O6 + 6O2
• Cellular Respiration formula: C6H12O6 + 6O2 -> 6CO2 + 6H2O + Energy (ATP)
• In ecosystems, energy flows from producers (autotrophs) to primary consumers (herbivores), then to secondary consumers (carnivores), and finally to tertiary consumers (top carnivores or apex predators).
• Energy transfer between trophic levels is about 10% efficient; only 10% of the energy stored as biomass in one trophic level is converted to biomass in the next trophic level.

Gross Primary Productivity/Net Primary Productivity

• Gross Primary Productivity (GPP) is the total amount of energy that producers capture via photosynthesis.
• Net Primary Productivity (NPP) is the energy that remains after accounting for the producers' respiration (R); NPP = GPP - R.
• NPP represents the storage of chemical energy available to consumers in the ecosystem.

Trophic Level Efficiency

• Trophic level efficiency = (production at the trophic level n / production at the trophic level n-1) * 100.
• This measures how well energy is transferred from one level to the next.

Biogeochemical Cycles

• Nitrogen Cycle: bacteria convert nitrogen gas into usable forms like ammonia (nitrogen fixation), then into nitrites and nitrates (nitrification); plants assimilate these, and denitrification returns nitrogen to the atmosphere.
• Water Cycle: evaporation, transpiration, condensation, precipitation, and runoff move water through ecosystems.
• Carbon Cycle: photosynthesis removes carbon from the atmosphere, respiration and combustion release it; carbon is stored in biomass, fossil fuels, and oceans.
• Phosphorus Cycle: weathering of rocks releases phosphate, which plants and animals use; sedimentation and geological uplift are long-term processes.
• Sulfur Cycle: sulfur is released from weathering rocks, volcanic activity, and decomposition; it cycles through the atmosphere, oceans, and land.

Biomes

• Biomes are large geographic areas with distinct climate conditions, animal populations, and plant communities.
• Examples include tundra, boreal forest, temperate forest, grassland, desert, and tropical rainforest.
• They're determined by factors like temperature, rainfall, and latitude.

Trophic Level Energy

• Energy in a trophic level is graphically represented by ecological pyramids, which illustrate energy flow or biomass at each level.
• Producers form the base, and successive levels diminish in size, reflecting energy loss.

Feedback Loops

• Positive feedback loops amplify changes, destabilizing a system.
• Negative feedback loops dampen changes, promoting stability.

Atmospheric Layers

• Troposphere: where weather occurs.
• Stratosphere: contains the ozone layer, which absorbs UV radiation.
• Mesosphere: where meteors burn up.
• Thermosphere: includes the ionosphere, heated by solar radiation.
• Exosphere: outermost layer, transitions into space.

Seasons

• Seasons result from Earth's axial tilt (23.5 degrees) and its orbit around the sun.
• Different parts of Earth receive direct sunlight at different times of the year.

El Nino/La Nina

• El Niño: unusually warm ocean temperatures in the equatorial Pacific, leading to altered weather patterns.
• La Niña: unusually cold ocean temperatures in the same region, also affecting global weather.

Equinoxes and Solstices

• Equinoxes: occur when the sun is directly above the Equator, resulting in equal day and night (vernal and autumnal equinoxes).
• Solstices: occur when the sun reaches its highest or lowest point in the sky at noon, resulting in the longest and shortest days (summer and winter solstices).
• Locations: Equinoxes (0 degrees latitude), Summer Solstice (Tropic of Cancer - 23.5 degrees N), Winter Solstice (Tropic of Capricorn - 23.5 degrees S).

Air Convection Currents

• Air Convection currents are driven by temperature differences.
• Warm air rises (less dense), and cool air sinks (more dense), creating vertical air movements and global wind patterns.