Ecology and Ecosystems Flashcards
the study of interactions of organisms with each other and with their environment
ecology
Three Basic Parts of Ecology
Interactions, organisms, environment
any attribute of the surroundings of an organism with which it interacts in any way.
environment
all living organisms in an area and their interactions with their abiotic environment
ecosystem
understand the distribution and abundance of living things in the physical environment
goal of ecology
how energy flows through them; minerals, such as nutrients, are reused over and over.
important aspects of ecosystems
consists of the physical characteristics of the area.
abiotic environment
composed of the resident organisms
biotic environment
_________ of the energy entering the system is lost as heat from one trophic level to the next.
90%
light energy is trapped and converted to chemical energy
photosynthesis
Photosynthesis equation
Solar Energy + Carbon Dioxide + Water —-> Carbohydrate + Oxygen
What can convert solar energy into usable chemical energy
photosynthetic organisms or producers
Who can use solar energy?
Producers can convert solar energy into chemical energy.
Who makes food for abiotic environments?
Producers/Autotrophs
energy cannot be created or destroyed; however, it can be converted into different forms (light, chemicals)
First Law of Thermodynamics
How does the first law influence energy use and the availability within an ecosystem?
Organisms use energy to remain organized and carry out life activities. Taking in energy and caring out life processes require changes in the form of energy. When the form of energy changes, some energy is lost.
When energy is transferred, some of the energy is lost as heat.
Second Law of Thermodynamic:
How does the second law influence energy used and the availability within an ecosystem?
The transformation of other forms of energy into heat constitutes a net increase in the randomness of the universe.
90% of the energy entering the system (sunlight - carbohydrates) is lost as heat from one trophic level to the next. Only 10% of the energy in a lower trophic level is transferred to the next. The higher trophic levels don’t get as much energy so there are less of them because there isn’t enough to support viable populations.
Energy Flow
5 common elements associated with organic molecules:
Carbon
Nitrogen
Hydrogen
Oxygen
Phosphorus
Relationship between energy flow and nutrient cycling
Energy flows directionally through ecosystems, entering as sunlight (inorganic molecules for chemoautotrophs) and leaving as heat during the many transfers between tropic levels.
The matter that makes up living organisms is conserved and recycled.
Geological processes (weathering, erosion, water drainage, and subduction of continental plates)
recycling of materials
What drives biogeochemical cycles?
Energy Flow
the recycling of inorganic matter between living organisms and their environment.
Biogeochemical Cycles
convert solar energy into useable chemical energy, photosynthesis organisms.
Producers
Produce their own food from inorganic materials.
Autotroph
break down waste or dead organic matter. Fungi and bacteria.
Decomposer/detritivores
Organisms that do need to consume other organisms in order to gain energy.
Consumer/Heterotroph
linear sequence of organisms through which nutrients and energy pass.
food chain
Plants, Algae, Phytoplankton
Primary Producers
organisms that feed directly on producers.
Primary Consumers
organisms that feed on primary consumers.
Secondary Consumers
carnivores that eat other carnivores.
Tertiary Consumers
organisms at the top of the food chain.
Apex Consumers
How much energy is transferred from one trophic level to the next?
10%
the total amount of energy that primary producers can pass to the second trophic level.
Net Primary Productivity
Producers can use some of this energy for their own ______________ and ______________, and also use some to produce __________________ _____________ that they accumulate.
maintenance, metabolism, organic compounds
NPP is measure in
Biomass
An indirect measure of the amount of energy that was used to produce tissue
Biomass
composed of organisms that share the same function in the food chain and the same nutritional relationship to the primary sources of energy.
Trophic Level
How many tropic levels can a species be assigned to?
one or more.
a graphic representation of a holistic, non-linear web of primary producers, primary consumers, and higher-level consumers used to describe ecosystem structure and dynamics. Interactions between different species and their complex interconnected relationships with each other and the environment.
Food Webs
are more flexible for analytical modeling, easier to follow, and are easier to experiment with.
Food Chains
linear sequence of organisms through which nutrients and energy pass
Food Chain
accurately represent ecosystem structure and dynamics, and data can be directly used as input for simulating modeling.
Food web models
NPP 1912
Grassland
NPP 550
Tundra
NPP 3059
Forest
NPP 271.5
Desert
NPP 1912, 585, 7648
Water Provinces
all organisms of one species living in the same area
Population
a group of organisms of a single species inhabiting the same geographic area.
Population Ecology
how many individuals of different age groups are in the population? – can lead to differences in present and future growth rates of populations.
Age Structure
% of female to males – for the population to grow quickly, there must be more females than males.
Sex Ratio
are individuals randomly dispersed or do they live in groups? Are groups small and dispersed or large and concentrated?
Population Distribution
Population Size (N)
number of individuals currently in the population
Number of Births (B)
number of individuals born into the population
Number of Deaths (D)
number of individuals who die in the population.
Per Capita Growth Rate (r)
a measure of how much each individual in the population changes the population size.
Population Size Equation
r = B-D/N
if something is increasing quickly, the quantity present gets larger faster with each increment of time.
Exponential growth
Exponential Growth Curve Shape
J Shaped Growth Curve
Exponential Growth Circumstances
Populations grow like this if they have unlimited resources. The population growth (G = the number of organisms added in each reproductive generation) is increasing at a greater and greater rate.
Equation for calculating future population size
population size in the future = population size now + change in population size
Exponential Growth Equation
G (population growth) =r (B-D) N (population size) G=rN
r = 0
r > 0
r < 0
Unchanged
Increasing
Decreasing
population size that represents the maximum population size that a particular environment can support.
Carrying Capacity (K)
How K limits population growth
If a population is at the maximum population size, then there can’t be anymore that are added to this population. There aren’t enough recourses to keep those additional organisms alive. Mathematical sanitization of the realities of famine, disease, and other causes of death.
Logistic Population Growth Curve Shape
S Shaped Curve
Logistic Population Growth
growth rate slows as it approaches carrying capacity.
Logistic Population Growth Circumstances
When resources are limited. When the number of individuals gets large enough, resources will be depleted, slowing the growth rate.
Logistical Population Growth Equation
G = rN * ((K – N) / K)
When N is very small, (K-n)/K is closer to
K/K or 1
Affect all individuals the same, no matter what the population size.
Density-Independent Factors
Affect individuals differently depending on population size.
Density-Dependent Factors
Density-Independent Factors Influence
All of the individuals are receiving the same factors no matter the population size, which allowed them to grow exponentially.
Density-Dependent Factors Influence
Some individuals are more dependent on these resources which makes it difficult for the population size to grow.
Why is human population growth look to be exponential and the implications of this for the future population?
It is taking less time to add a particular number of humans to the Earth. We are increasing rapidly. Because humans are increasing rapidly, people are worried that the ability of the earth’s environment to sustain this population will end up having potential risks of famine, disease, and large-scale death.
a group of species that are commonly found together.
Ecological Community
how species interact with each other and what processes determine the patterns of species coexistence, diversity, and distribution.
Community Ecology
all populations of all species interacting within a particular environment.
Community
Two factors that describe a community
Composition and Diversity
Richness: How many different species?
Evenness: How many individuals are in each population?
Diversity
What species are present?
Composition
interactions that occur between the population of the different species.
Interspecific Interactions
interactions that occur between the population of the same species.
Intraspecific Interactions
one species is benefited (+) and one species is neither harmed or benefited (O) (Remoras: + Sharks: O)
Commensalism
both species benefited (+,+) (Termites: + Non-Woody Vascular Plants: +)
Mutualism
both species are harmed (-,-) (Myrtle Warbler: - Cap May Warbler: -)
Competition
One species benefited (+) and one species harmed (-) (Cat: + Mouse: -)
Predation
parasite benefit (+) and host are harmed (-)
Parasitism
one individual harmed (-) and the other isn’t harmed or benefited (O
Amensalism
the subdivision of some category of similar resources.
Resource Partitioning
Resource partitioning can reduce competition because
it allows organisms to realize that they have to share the resources with others. There has to be a carrying compacity so that there are enough resources for all of the organisms.
the reciprocal genetic charge over time of two or more interacting species and it can take many forms.
Coevolution
Examples of Coevolution
Predator/Pray
Bats vs Frogs
Frogs use songs to attract female frogs. One song (simple song) keeps the frogs safe from the bats, but it doesn’t attract as many females. The other song (sexy song) makes the frogs at risk from the bats, but it attracts more females.
developmental process of communities.
Succession
the process that occurs in an area that begins with no living organisms.
Primary Succession
Examples of Primary Succession
newly created volcanic island or bare rock exposed after the retreat of glaciers.
existing ecological communities are distributed and then allowed to return to their original state
Secondary Succession
Examples of Secondary Succession
fires, human activities
