a particular location on Earth distinguished by its particular mix of interacting biotic and abiotic components.
ecosystem
Biotic and abiotic components provide the boundaries that distinguish one ecosystem from another. Some ecosystems have very clear boundaries, others do not. (subjective)
Ecosystem boundaries (2)
use photosynthesis
autotrophs
CO?+H?O+sun energy?C?H??O?(glucose)+O?
photosynthesis
unlocks the chemical energy stored in organisms: the opposite of photosynthesis.
cellular respiration
consume other organisms for energy
heterotrophs
herbivore
primary consumer
carnivore, eats primary consumer
secondary consumer
carnivore, eats secondary consumer
tertiary consumer
successive levels of organisms consuming one another
trophic levels
carnivores that consume already dead animals
scavengers
specialize in breaking down dead tissues and waste products into smaller particles. Do not return nutrients to soil. (step 1)
detrivores
fungi and bacteria the complete the breakdown process by recycling the nutrients from dead tissues and wastes back to the ecosystem. (step 2)
decomposers
total amount of energy that the producers in an ecosystem capture via photosynthesis in a given amount of time.
gross primary productivity (GPP)
NPP=GPP-respiration by producers, allows us to compare the productivity of different ecosystems or measure changes in one ecosystem
net primary productivity (NPP) (2)
the total mass of all living matter in a specific area, can be used to measure the energy in an ecosystem.
biomass (2)
the amount of biomass present in an ecosystem at a particular time (amount, not rate.)
standing crop
NPP
How is the rate of biomass production measured?
the proportion of consumed energy that can be passed from one trophic level to another.
ecological efficiency
10%
What is an average ecological efficiency?
the population size of the various species within each trophic level.
What does the flow of energy between trophic levels help to determine?
the region of our planet where life resides. formed by a combination of all ecosystems on earth. 12 mi thick shell.
biosphere (3)
energy flows through, matter cycles within
Difference between energy and matter with relation to biosphere
the movement of natter within and between ecosystems
biogeochemical cycles
the components that contain matter
pools
processes that move matter between pools
flows
it helps us to understand how ecosystems function and the ways in which human activities can alter these processes.
why is it important to understand the sources of elements and how they flow between biotic and abiotic components of ecosystems?
evaporation/transpiration, condensation, precipitation
steps of hydrologic cycle (3)
plants release water from their leaves during photosynthesis
transpiration
combination of evaporation and transpiration, scientists use this to measure water moving through an ecosystem
evapotranspiration
photosynthesis, respiration, exchange, sedimentation and burial, extraction, comblustion
steps of Carbon cycle (6)
nitrogen fixation, assimilation, ammonification, nitrification, denitrification
steps of nitrogen cycle
N??NH?/NO???NH??
nitrogen fixation
producers assimilate fixed nitrogen into tissues
assimilation
fungus and bacteria use nitrogen-containing wastes and dead bodies as a food source and excrete ammonium. (NH??)
ammonification
bacteria convert NH???NO???NO??
nitrification
bacteria convert NO???N?O?N?
denitrification
can limit an environment's biodiversity
Excess Nitrogen
weathering, runoff, excretion and decomposition, precipitation, geological uplift
Phosphorus Cycle steps
contributes phosphates to the land.
weathering
runoff from fertilizer goes to streams, becomes part of soil, or is absorbed by plants
runoff
release phosphates on land or in water
excretion and decomposition
dissolved phosphates precipitate from solution and contributes to ocean sediments. slowly become phosphate rocks.
precipitation (phosphate cycle)
geologic forces slowly lift phosphate rocks from the ocean to form mountains.
geologic uplift
caused by excess phosphorus, raises biomass significantly. when algae dies, the decomposition uses a lot of oxygen resulting in hypoxic conditions. fish die.
algal bloom
fertilizer, household detergents
sources of excess phosphorus (2)
dissolve in water. not present as gas but travel through air as dust. from rocks, decomposed vegetation.
Calcium, Magnesium, and Potassium (4)
attracted to soil. limestone, marble
Ca�? and Mg�?
leached into water, leads to potassium-deficient soil
K?
in rocks, released over time. component in protein, allows organisms to use oxygen.
sulfur (2)
plants absorb through roots
SO?�?
released from volcanoes, burning of fossil fuels, mining metals
SO?
acid rain
SO?+H?O?H?SO?
an event caused by physical, chemical, or biological agents that results in changes in population size or community composition, can be natural or anthropogenic
disturbance
all the land in a given landscape that drains into a particular stream, lake, or wetland
watershed
a measure of how much a disturbance can affect the flow of energy and matter
resistance
the rate at which a system returns to its original state, can depend on interactions between biogeochemical and hydrologic cycle.
resilience
ecosystems experiencing intermediate levels of disturbance are more diverse than those experience high or low levels of disturbance
the intermediate disturbance hypothesis
species can be used as a tool to accomplish a goal
instrumental value
has worth independent of any benefit it may provide to humans/moral obligation
intrinsic value
goods humans can use directly
provisions
regulate environmental conditions
regulating services
provide support systems that would be very costly for humans to generate
support systems
depends on species diversity
resilience
cultural/aesthetic benefits, intellectual gain
cultural services