Intro to Ecology Flashcards
Ecology
- the study of how organisms interact with each other and their corroding environment
- strives to understand the distribution and abundance of organisms
- interdisciplinary
Population
a group of individuals of a species in the same general geographic area at the same time
Community
all of the populations of different species that interact with each other in a defined
Ecosystem
all of the organisms that live in a defined area, plus the abiotic components
Biome
large region characterized by distant abiotic characteristics and dominant types of vegetation
What three general types of characteristic determine the distribution and abundance of organisms?
Abiotic, biotic, and history
What is the importance of the abiotic environment?
- because of fitness trade-offs, organisms tend to be adapted to a limited set of physical conditions
- this results in their geographic distribution (range)
Niche
the range of resources that a species can use and the range of conditions that it can tolerate
e.g. microbes used to different extreme temperatures; availability of resources
Biotic factors
- interactions among organisms
- can be negative, positive, or neutral
What are examples of negative biotic factors?
Competition
Parasitism
What are examples of positive biotic factors?
Mutualism
Historic factors
- abiotic and biotic characteristics change over time
- distributions are dependent on the slice of time being analyzed
- E.g. the North and South American Species with and without the Pan-American land bridge
What are the 6 different Biomes?
- Arctic Tundra
- Boreal Forest
- Temperate Forest
- Temperate Grassland
- Subtropical Desert
- Tropical Wet Forest
What are the variables shaping the climate?
Temperature
Moisture (Precipitation)
Sunlight
Wind
What are the two variables that are used best to differentiate climates?
Temperature and Moisture (Precipitation)
Net primary productivity (NPP)
- The total amount of biomass generated by the fixation of carbon per year minus the amount that is oxidized during cellular respiration
- the greater the NPP, the better the biome is able to support larger and increasingly diverse communities
What is biomass?
the total mass of organisms
e.g. primary producers in the case of NPP
Whittaker’s Biome Concept
- created by Robert Whittaker
- plotted precipitation against temperature
- the zones form a triangle on the graph
What are the three different zones of temperature in the Whittaker Biome Concept?
Tropical
Temperate
Boreal/Polar
What are the two different zones of precipitation in the Whittaker Biome Concept?
Forest
No Forest
Circulation Cells (Hadley Cells)
The circulations formed in areas by the equator because of the direct angle of sunlight involving a lot of moisture around the equator and little moisture outside of that area
- more solar energy causes more heat
- the heat rises
- the more heat causes more evaporation
- as the water cools as it evaporates, it eventually drops as rain
- the now dry air is pushed towards the poles
- the dry air descends, warms, and absorbs moisture
- wet forest around equator and dry areas outside towards the poles
What is seasonality caused by?
- it is caused by the Earths tilt on its axis by 23.5 degrees
- whether the hemisphere is tilted away or towards the sun produces the season
Microclimate
the climate in a very small area
-e.g. the north face vs the south face
What is a rain shadow?
The area that receives dry air on a specific side of a mountain due to a a source of water on the other side of the mountain and a wind current carrying the moist air from the body of water towards the mountain
What are the foundation of terrestrial biomes?
Soils
What is soil?
A complex mixture of living a non-living material
How are soils classified into different layers and kinds?
By compositions, organic matter, minerals, particle size, porosity, and granularity
O layer
rich in nutrients and organic material
Permafrost Soils
- ground frozen for extended time periods (usually > 2 yrs)
- at high latitudes (tundra and parts of boreal forest) and altitudes
- prevents tree growth
- low decomposition due to the cold -> accumulation of organic matter
Carbon Sink
-occurs by dead animals pulling CO2 from the atmosphere and storing it
Temperate Grasslands Soils
- Deep, basic/neutral pH, and lots of organic matter
- high nutrient availability
- great for agriculture
Tropical Rain Forest Soils
- often low in organic matter due to high rates of decomposition and uptake by plants
- yet, nutrient levels can be high near river and volcanoes
- slash-and-burn agriculture
Mychorrhizae fungi
- an example of a mutualistic relationship involving plants
- get around roots of plants
- plants receive nutrients
- fungi receive carbohydrates produced by the plant
Nitrogen-fixing Bacteria
- an example of a mutualistic relationship involving plants
- plants have issues fixing nitrogen in the atmosphere so that it can be used to create biomass
- plants receive nitrogen
- bacteria receive a stable environment and carbohydrates
How much of the Earth’s surface is covered by water?
71%
What are the four abiotic features that best define aquatic biomes?
Salinity
Depth
Flow
Nutrients
Osmoregulation
processes that control the water and the solute concentrations in organisms
-stenohaline; euryhaline
Stenohaline
- able to tolerate narrows range of salinity
- most species
- determined over time by natural selection
Euryhaline
- able to tolerate large changes in salinity
- few species
- better for estuaries
Saltwater Fish
- blood is hypotonic
- lower amount of salts compared to surrounding water
- expected to lose water by osmosis
- replaces water by drinking seawater
- produce a small amount of concentrated urine (small amount of dark yellow pee)
Freshwater Fish
- blood is hypertonic
- greater amount of salts compared to surrounding water
- expected to gain water by osmosis
- produce large amounts of dilute urine
- the do not drink much of the surrounding of water
As depth increases…
Temperature decreases
Pressure Increases
Light decreases
By what depth does 50% of light is absorbed by?
10 meters
Ocean Net Primary Production
- NPP is typically low
- it is higher by coasts
Kelp
- high NPP
- marine, multicellular brown algae
- temperate and high latitudes
- buoyant, but anchored with holdfasts
- air sacs keep them upright
-holdfasts = like a root system
high productivity
- diverse communities live in kelp forests
- kinda like a forest
Coral
- High NPP
- marine invertebrates
- corals are tiny little polyps in the same family of jellyfish, millions of them make up a colony resulting in one coral
- host colorful zooxanthellae algae
- the algae cause vibrant colors and do photosynthesis
- in tropical areas
Coral Bleaching
- the loss of color when coral expel their zooxanthellae
- occurs with warmer water temps
Streams
- fast flowing
- greater potential for erosion
- maintains colder temperature longer
- poses challenges for organisms to not be swept away
- higher oxygen and better aerated
Bog
- little or no water flow
- low oxygen and nutrient poor
- together with low temps, low decomposition
Wetlands
- marshes and swamps
- higher water flow compared to bogs
- more oxygen and nutrients compared to bogs
- more oxygen and nutrients
- greater productivity
- more diverse community
Nutrient availability
- often in short supply
- added or removed by currents in streams
- sink to bottom, away from light
Ocean Upwelling
- Winds blow
- Surface water moves and is forced offshore
- Upwelling- as the surface water leaves it is replaced by nutrient-laden water welling up from the bottom
Thermocline
-a steep gradient in environment temperature
Winter Stratification
Dense 4°C water at the bottom becomes nutrient rich while colder water a near the surface becomes oxygenated
Lake turnover
- Winter Stratification
- Spring Turnover- surface water warms to 4°C and sinks carrying O2 down and nutrients up
- Summer Stratification- Dense 4°C at the bottom becomes nutrient rich while warmer water near surface becomes oxygenated
- Fall turnover- surface water cools to 4°C and sinks carrying O2 down and driving nutrients up
El-Niño Southern Oscillation (ENSO)
-changes Pacific sea surface temperature which affects weather around the world
What are the three cyclical climate patterns that ENSO can cause?
El Niño
La Niña
Neutral
How does ENSO affect the western coast of South America?
- warm water and less wind
- less upwelling of cold nutrient-rich water
- negative for fish and seabird populations
- hurts the fisheries and fertilizer industries
- especially hurts the Anchoveta fish
Weather
-short term (minutes to months) variation in the atmosphere
Climate
-descriptor of long-term weather pattern in a specific area
What type of correlation is there between temperature and CO2?
Positive Correlation
What are the five Aquatic Biomes?
Lakes and Ponds Freshwater Wetlands Streams Estuaries Oceans
The Intertidal Zone
- consists of a rocky shoreline, sandy beach, or mud flat
- exposed to the air at low tide but submerged at high tide
The Neurotic Zone
- extends from the intertidal zone to depths of about 200 m
- its outermost edge is defined by the end of the continental shelf
Continental shelf
-the gently sloping, submerged portion go the continental plate
The Oceanic Zone
- the open ocean
- the deepwater region beyond the continental shelf
The Benthic Zone
-the bottom of the ocean at all depths
The Photic Zone
-the intertidal zone and sunlight regions of the neurotic, oceanic, and benthic zones
The Aphotic Zone
-the areas that do not receive sunlight
Turbidity
the cloudiness of water
Detritus
dead organic matter
Estuaries
where freshwater creeks and rivers meet the sea
The Littoral Zone
-consists of the waters along the shore that are shallow enough for plants to take roots
The Limnetic Zone
-is offshore and comprises water that receives enough light for photosynthesis but that is too deep for plants to take root
Biogeography
-the study of how organisms are distributed geographically
The biosphere
-a thin zone surrounding the earth where all life exists
Conversation biology
-the effort to study, preserve, and restore threatened genetic diversity in populations, specific diversity in communities, and ecosystem function
The Coriolis effect
- the tendency for moving air on water to be deflected from a straight path
- accounts for for the different directions of the prevailing winds and ocean currents at different latitudes
An exotic species
one that is not native
Invasive species
-an exotic species that is introduced into a new area, spreads rapidly, and competes successfully with native species
Dispersal
the movement of individuals from their place of origin to the location where they live and breed as adults
The Wallace Line
the biogeographical demarcation that separates species with Asian and Australian affinities
What are the 5 Lake Zones?
The Littoral Zone The Limnetic Zone The Photic Zone The Aphotic Zone The Benthic Zone
What are the 6 Ocean Zones?
The Intertidal Zone The Neritic Zone The Oceanic Zone The Photic Zone The Aphotic Zone The Benthic Zone
Water has an extremely ______ specific heat.
high
Specific heat
the capacity for storing heat energy
gyres
the circles that ocean currents move in
aboveground biomass
- the total mass of living plants, excluding roots
- how NPP is often estimated
Under what conditions are photosynthesis, plant growth, and NPP maximized on land?
Warm temperatures and wet conditions
Global Warming
refers to the increase in the average temperature of the planet
Global climate change
refers to the sum of all the changes in local temperature and precipitation patterns that result from global warming
Weather
the short term highly variable atmospheric conditions such as temperature, moisture, sunlight, and wind in a specific area and time
Climate
refers to the long term average pattern of regional or global weather
Phenology
the study of the timing of seasonal events
Who is researched CO2 concentration and the up and down pattern each year?
Keeling
