APES - Unit 2 - Ecosystem Ecology, Climate, & Biomes

Energy flow in an ecosystem

one way stream of from primary producers to consumers, only 10% of energy is transferred from one tropic level to the next (energy lost through respiration, waste and death)

Photosynthesis

the process by which producers/autotrophs convert light energy into chemical energy, creating food (glucose)/oxygen from CO2/water, only about 1% efficient

Cellular Respiration

the opposite of photosynthesis, converts glucose/oxygen into CO2/water and energy(ATP)

Trophic Levels

the first level has the largest biomass and is made of producers/autotrophs, 2nd level is primary consumers including herbivores, 3rd level is secondary consumers (carnivores) eating 1st and 2nd levels, and 4th is the smallest and tertiary consumers (carnivores) that eat it all

Heterotrophs

opposite of autotrophs, get energy from eating other things, cannot produce its own food like autotrophs photosynthesizing

Scavengers

carnivores that eat dead animals (like vultures)

Detritivores

break down dead tissues and waste products (detritus) into smaller particles (dung beetles)

Decomposers

complete the breakdown process by recycling the nutrients back into the ecosystem (fungi//bacteria)

Gross Primary Productivity (GPP)

total amount of solar energy that the producers in an ecosystem capture via photosynthesis over an amount of time, measured in biomass

Net Primary Productivity (NPP)

the total amount of energy captured by the producers minus the energy used in respiration

Biomass

total mass of all living matter in a specific area

Ecological Efficiency

the proportion of consumed energy that can be passed from one trophic level to another - 10% on average

Biogeochemical Cycles

movements of matter within and between ecosystems, includes biological/geological/chemical processes - keep track with the flow of pools of matter

Nitrogen Cycle

1. Nitrogen Fixation (nitrogen fixing bacteria converts N2 gas into solid NH3 or NO3),

2. Assimilation (producers take up NO3 through the soil),

3. Decomposition (consumers that ate the producers create waste and eventually die, both decompose into NH4),

4. Nitrification (Nitrifying bacteria converts NH4 into NO2 then NO3),

5. Denitrification (denitrifying bacteria convert solid NO3 into N2 gas)

Carbon Cycle

CO2 in the air photosynthesizes into producers, producers are eaten by consumers (cellular respiration) and then die and turn into detritus, then decomposition returns CO2 into the atmosphere. If no producers photosynthesize the CO2 in the air it sediments into limestone (CaCO3). If there is no air for the detritus to decompose then anaerobic decomposition turns it into CH4

Hydrologic Cycle (Water)

evaporation takes the water from liquid to gas, then condensation in clouds turns it back into liquid, it precipitates back down to earth and ends up as runoff into a body of water (then evaporated again) or is uptaken by plants, from there transpiration releases water vapor back up to the clouds.

Phosphorus Cycle

Phosphate in soil can be taken in by plants that either are eaten or turn to detritus, both decompose and return to the soil. Runoff of phosphate into the ocean gets taken in by marine producers that are either eaten or turn to detritus. Fertilizer adds substantial amounts of extra phosphorus into the soil (lots run off and cause algae blooms).

Algae Bloom

excessive phosphorus from human waste/fertilizer cause rapid overgrowth of algae (cyanobacteria) in water that can block the sun, effect temperature, change salinity, and produce toxins (take too much oxygen from the water - kills fish)

Eutrophication

excess nutrients (nitrogen/phosphorus) get released into water - algae/phytoplankton use the nutrients and bloom (skyrocket population) - algae blocks light which kills other plants - creates excessive detritus which uses all of the oxygen in the water - without oxygen water becomes a dead zone - water with little O2 (hypoxic), water with no O2 (anoxic)

Ecosystem Services

benefits that humans obtain from natural ecosystems in 5 categories: provisions, regulatory services, support systems, resilience, cultural services

Climate

Average weather that occurs in a region over a long period (decades)

Troposphere

first atmospheric layer closest to earths surface (16k/10m) densest, lots of circulation, where weather occurs and greenhouse gases are, from earths surface to stratosphere, gets less hot as you go up

Stratosphere

second atmospheric layer above the troposphere, slightly less dense, contains the Ozone Layer (03), warmer because UV reaches higher altitudes first - sunlight is absorbed here (keeps warmth)

The Ozone layer

pale blue gas made of O3, in the stratosphere, absorbs most of suns UV-B and all of UV-C radiation (O2 + UV = O + O which then bind with O2s to create O3), Ozone Hole created by O3 binding to UV and breaking into O2 and O, and CFCs putting chlorine in the atmosphere that breaks O3 into O2 - leaves not enough O3 in the Ozone Layer which allows too much radiation to get to earths surface leading to skin cancer, cataracts, DNA damage etc.

CFCs

Chlorofluorocarbon molecules that break O3 (ozone gas) into O2 and leave the Cl unchanged to break down more O3, in aerosols, fridges and air conditioners until Montreal Protocol banned them in the 80s

Mesosphere

third layer of the atmosphere above stratosphere, no absorption of any heat so is the coldest layer (-138 C), where most meteors burn up/shooting stars

Thermosphere

fourth layer of the atmosphere above mesosphere, blocks harmful X-ray and UV radiation, Super Hot bc absorbs suns rays, aurora borealis from reactions with gases

Exosphere

fifth and last layer of the atmosphere above the thermosphere, thins out and merges with space

Greenhouse Effect

Greenhouse gases (H2O, CO2, CH4, CFCs, N20) absorb radiation coming off the ground (bounce) and reradiate the infrared heat in the troposphere, critical to survival bc without it earth would have a polar climate at night 

Unequal Heating of the Earth

the suns rays hit the earths surface at different angles which either focus or spread out the heat in different areas/latitudes

Albedo Effect

the amount of solar energy reflected off the earths surface - low= dark(oceans/cities)+hot temps, high= light(ice/snow)+cold temps — opposite of temperature

Atmospheric Convection

hot air rises (less dense), air moves to areas of less pressure and expand and cool (adiabatic cooling) as it cools it condenses again into liquid and rains, condensation causes latent heat release warming the air again which then rises

Adiabatic Heating

when air sinks toward earth pressure increases, which makes the air less dense which raises the temperature of the air

Hadley Cells

convection currents between the the equator and 30 N/S, the InterTropical Convergence Zone (ITCZ) is the area by the equator with the most direct sunlight, dense clouds/rain where the warm, moist air rises, moves polewards at high altitudes, cools, and then sinks in the subtropical regions (around 30° latitude) before returning to the Equator near the surface (adiabatic heating), drives global wind patterns

Coriolis Effect

the effect that the spinning of the earth has on objects (wind) that move over a long distance, in the Northern hemisphere things are deflected right (northerns always right), in the Southern Hemisphere things are deflected left

Prevailing Winds

the combination of convection currents (air rising at equator) and Coriolis Effect, Trade winds go towards equator to the left, Westerlies/Easterlies go towards poles to the right

Trade Winds

winds going left towards the equator from 30 N/S

Westerlies/Easterlies

Winds going right to the poles from 30 N/S

Rainshadow Effect

when wind meets a mountain range near the ocean, wind blows the warm wet air in from the ocean then gets driven up by the mountains and condenses and falls back down on the ocean side of the mountain range, on the other side of the mountain range is dessert/very dry climate 

Gyres

Large circular surface current patterns in the ocean, bring warm water up with trade winds then brings cool water down against trade winds, 2 spin right in the Northern Hemisphere and 3 spin left in the southern hemisphere

Ocean’s Impact on Climate

water has a high heat capacity (stores lots of heat), that it transports around the globe, ocean absorbs heat in the summer and releases it in the winter, therefore wind coming off the water in the summer is cold and in the winter it is warm - this is what makes coastal locations have more moderate climates

Upwelling

upward movement of water towards the surface that brings up nutrients the sank, the nutrients feed the producers and support larger food chains - explosion of life/productivity, cold current=upwelling zones 

Thermohaline Circulation

hot salty water gets dense and sinks in the North Atlantic, then travels as a deep ocean current (zigzag) until it warms and joins the surface currents again

El Nino Southern Oscillation

El Nino is the natural phenomenon in the pacific of abnormally warm ocean temps - it changes the trade winds causing ocean current changes, upwelling and precipitation shifts — La Nina is counterpart cold phase — they swing back and forth every few years, neutral phase also exists when conditions are neither El Niño nor La Niña

Land Biomes (Cold - Hot)

Tundra, Boreal Forest, Temperate Rainforest, Temperate Seasonal/Deciduous Forest, Woodland/Shrubland, Temperate Grasslands, Tropical Rainforest

Tundra

a harsh, cold, and dry biome characterized by the absence of trees and permafrost (a layer of permanently frozen soil that limits deep root growth for plants), little precipitation, very slow decomposition, towards poles 

Boreal Forest

long, cold winters and short, mild summers, and dominated by coniferous trees such as spruce and fir, low precipitation, around 60 N/S, low biodiversity/ nutrient poor soil, slow decomposition bc of needles

Temperate Rainforests

high rainfall and mild temperatures, foggy summers/rainy winters, diversity of life, coniferous trees, ferns, mosses - long growing seasons, mid latitudes (40-60*), coastal, slow decomp bc of needles - low soil nutrients

Temperate Seasonal / Deciduous Forest

middle latitudes characterized by four distinct seasons, moderate precipitation, and deciduous trees that shed their leaves in the fall, mid latitudes (25-50*) - longer growing season, rapid decomp bc of leaves, better soil nutrients (agr)

Woodland/Shrubland

hot, dry summers and cool, moist winters, full year growing seasons, low precipitation, drought resistant shrubs - coastal 30-40* latitudes - frequent wildfires, low soil nutrients (leeching from rain)

Temperate Grassland/ Cold Desert

grasses, few trees, moderate/seasonal rainfall, distinct hot summers and cold winters. mid-latitudes, prairies, long growing season, crucial for agriculture due to nutrient rich soils, fires and wind common

Tropical Rainforest

hot, humid, and extremely biodiverse biome found near the equator ITCZ (20 N/S), dense, evergreen forests and tree canopy, high rainfall year-round. soil is surprisingly nutrient-poor due to the constant leaching of nutrients by heavy rains and rapid decomposition

Savanna / Tropical Seasonal Forest

scattered trees, distinct wet and dry seasons, and warm, year-round temps. During wet season, abundant rainfall and dense vegetation growth, while dry season brings severe drought - ITCZ 10-20 latitudes - used for agriculture

Subtropical Desert

extremely high temperatures, very minimal precipitation, and sparse vegetation adapted to arid conditions, 15-30 latitude

Freshwater Biomes

Flowing Water: streams and rivers (high oxygen environments, high nutrients) — Standing Water: lakes and ponds (littoral, limnetic, profundal and benthic zones)

Littoral

freshwater biome, edge of lakes, ponds, rivers, and oceans, where land meets water, shallow area of soil/water near shore where algae and emergent plants grow

Limnetic Zone

freshwater biome, surface layer of a lake or pond that extends from the shore to the point where light penetration is insufficient for photosynthesis, open water, rooted plants cannot survive, only floating algae (phytoplankton)

Profundal Zone

freshwater biome, a lake's deep, dark, open-water layer where sunlight cannot penetrate, making photosynthesis impossible (aphotic), no producers, only bacteria

Benthic Zone

Freshwater biome, muddy bottom of lakes, organisms called benthos, cold, high pressure, and limited to no light. 

Freshwater Wetlands

Swamps, marshes, bogs; soil that is saturated by water for at least part of a year, shallow enough to support emergent vegetation - one of the most productive ecosystems - provide services like erosion/flooding prevention, filtration of water, and habitat for ¼ of commercial fish larvae 

Salt Marshes and Estuaries

along coast of temperate climates, emergent vegetation, very productive - where fresh water rivers mix with salty ocean - important habitat for spawning fish/shellfish (2/3 of fish larvae)

Marine Biomes

Intertidal zone, Coastal zone, Open ocean (Photic, aphotic, benthic)

Productivity in the Ocean

life in the ocean is concentrated at the surface, limiting factors of sun and nutrients limit producers and therefore most ocean life to the photic zone (coast’s continental shelf 50m)

Intertidal Zone

Marine Biome, small area between low and high tide, can be steep/rocky or mudflats, harsh environment due to big changes in temperature, water, waves, heat and wind

Coral Reefs

most biodiverse and important marine biome, in the continental shelf of the tropics, corals deposit limestone that function as housing for algae that pays with sugar and CO2 (mutualism)

Coral Bleaching

the algae inside of the corals die (low pH/high water temps) which causes the corals to die and turn white - loss of a major habitat for ¼ of ocean life

Open Ocean Desert

very little/scattered life, lack of nutrients leads to no producers and therefore no food web

Photic Zone

Marine Open Ocean Zone, surface water, enough light for photosynthesis

Aphotic Zone

Marine Open Ocean Zone, deep ocean, no photosynthesis, very little life

Oligotrophic lakes

low productivity bc of low nutrients

Eutrophic lakes

High productivity