Post on 04-Jan-2016
Ecology review:
What is Ecology? (a brief review)
• Ecology-
• the study of interactions between– organisms and organisms– organisms and their environment
Where do we fit in?
(What is our environment?)
The Biosphere!
Factors that effect us:1. Abiotic Factors
Wind/Air currentsMoisture
Soil
Light
Temperature
• A- stands for non• Bio- stands for living
• Abiotic Factors- nonliving factors
2. Biotic Factors:
• Biotic- Living factors
What is the organization of Ecological Study?
Population
Community
Ecosystem
Biosphere
Organism
Levels of Organization• Individual- one
organism (living)
• Ex a moose
Levels of Organization• Population- groups
of individuals that belong to the species and live in the same area. (living-living same species)
• Ex many moose
Levels of Organization
• Community- groups of different populations (more than one population or different groups of species)
Ex many groups of moose beavers, trees, grass (all living)
Levels of Organization• Ecosystem- all
organisms in a particular area along with the nonliving. (living and nonliving)
Ex many groups of moose beavers, trees, grass, rocks, water, mountains
Levels of Organization
• Biome- group of ecosystems that have the same climate and similar dominant communities
• Biomes: tropical rain forest, tropical dry forest, tropical savannah, temperate grassland, desert, temperate woodland and shrubland, temperate forest, northwestern coniferous forest, boreal forest (taiga), tundra, mountains and ice caps
Levels of Organization• Biosphere- all of the
planet where life exhists, includes land, water, and, air
• Life extends 8 km up and 11 km below the surface
IN AN ECOSYSTEM:
Organisms live in a Habitat
Organisms fit into a Niche of the environment
Habitat vs. Niche• Habitat- an area where an organism lives • Niche- an organisms role in its environment
– The Long Version full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions. Includes where in the food chain it is, where an organism feeds
• Habitat is like an address in an ecosystem and a niche is like an occupation in an ecosystem.
ENERGY FLOW
Autotrophs vs. Heterotrophs
Energy Flow (Trophic Levels)• Producers- make
their own food• Consumers- get
energy from consuming producers
Producers• Producers- capture
energy from sunlight or chemicals and use the energy to produce food.
• Producers are autotrophs- they make food from their environment
2 main types of autotrophs• One type gets energy
from the sun-by photosynthesis
• Another type gets energy without light- by chemosynthesis
Consumers• Consumers are
heterotrophs- get energy from other organisms
Types of Consumers• Herbivores- eat only plants• Carnivores- eat animals• Omnivores- eat both plants and animals• Detritivores- eat dead matter (plants and
animals)
Feeding Relationships• Energy flows through an ecosystem in one direction
from:– 1. the sun or inorganic compounds– 2. To autotrophs (producers)– 3. To heterotrophs (consumers)– Decomposers get energy from decomposing dead
organisms
Food Web- A network of feeding relationships.
(More realistic that a food chain)
Food Chain- a series of steps in which organisms transfer energy by eating or being eaten.
Food Web
They can become very complex!
Trophic levels
• Each step in a food chain or a food web is called a trophic level.– Producers are the first
trophic level– Consumers are the
second, third, or higher trophic level
• Each trophic level depends on the one below for energy
Energy Pyramid• Only part of the energy
stored in one level can be passed to the next- most energy is consumed for life processes (respiration, movement, etc., and heat is given off)
• Only 10% of the energy available within one trophic level is transferred to organisms in the next trophic level
Biomass Pyramid• Biomass- the total
amount of living tissue within a given trophic level.
• A biomass pyramid represents the amount of potential food available for each trophic level in an ecosystem.
Energy Losses
• Energy transfers are never 100 percent
efficient
• Some energy is lost at each step
• Limits the number of trophic levels in an
ecosystem
• Energy flow is a one way path! (not a cycle)
All Heat in the End
• At each trophic level, the bulk of the energy received from the previous level is used in metabolism
• This energy is released as heat energy and lost to the ecosystem
• Eventually, all energy is released as heat
• All living organisms need certain elements/compounds for life processes– Ex: your cells need C,H,O,P,N & S in order to
live and reproduce (make more cell)
• Cycles in nature keep these elements “moving” from organisms to organism (and sometimes into the atmosphere)
Biogeochemical Cycles(Matter moving through the environment)
Biogeochemical Cycles(Matter moving through the environment)
• The flow of a nutrient from the environment to living
organisms and back to the environment
• Main reservoir for the nutrient is in the environment
• Transfer rates to and from reservoir are usually lower
than the rates of exchange between and among
organisms.
• Matter is recycled through an ecosystem – not one way
flow
Three Categories
• Hydrologic cycle
– Water
• Atmospheric cycles
– Nitrogen and carbon
• Sedimentary cycles
– Phosphorus and sulfur
CYCLES IN NATURE
Carbon Cycle
• Carbon moves through the atmosphere
and food webs on its way to and from
the ocean, sediments, and rocks
• Sediments and rocks are the main
reservoir
Carbon Cycle
photosynthesisTERRESTRIAL
ROCKS
volcanic action
weathering
diffusion
Bicarbonate, carbonate
Marine food webs
Marine Sediments
Atmosphere
TerrestrialRocks
Soil WaterPeat, Fossil
Fuels
Land Food Webs
Carbon in Atmosphere
• Atmospheric carbon is mainly carbon dioxide
• Carbon dioxide is added to atmosphere– Aerobic respiration, volcanic action,
burning fossil fuels, decomposition of organic materials
• Removed by photosynthesis
Nitrogen Cycle• Nitrogen is used in amino acids and nucleic acids
(all living organism need nitrogen to make
proteins)
• Main reservoir is nitrogen gas in the atmosphere
• Decomposers are vital to convert ammonia into:
1. usable nitrites & nitrates for plants (nitrogen fixation)
2. nitrogen gas (denitrification = puts it back into the atmosphere)
Phosphorus Cycle• Phosphorus is part of phospholipids and all
nucleotides
– What are these?
• It is the most prevalent limiting factor in
ecosystems
• Main reservoir is Earth’s crust; no gaseous
phase (it never enters the atmosphere – like
carbon and nitrogen)
Phosphorus Cycle
GUANO
FERTILIZER
ROCKS
LAND FOOD WEBS
DISSOLVED IN OCEAN
WATER
MARINE FOOD WEBS
MARINE SEDIMENTS
excretion
weathering
mining
agriculture
uptake by autotrophs
death, decomposition
sedimentation setting out leaching, runoff
weathering
uplifting over geolgic time
DISSOLVED IN SOILWATER,
LAKES, RIVERS
uptake by autotrophs
death, decomposition