Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Chapter 3: Ecosystem Ecology
Transcript of Chapter 3: Ecosystem Ecology
An ecosystem is a particular location on earth distinguished by its mix of interacting biotic and abiotic components. Components of ecosystems could be (biotic) trees, wildflowers, birds, mammals, insects, fungi, and bacteria, etc. Abiotic components of an ecosystem determine which organisms can live there.
•How would you know when you left one ecosystem and entered another?
Determining where one ecosystem ends and another begins is difficult because boundaries are often subjective. Environmental scientists might define a terrestrial ecosystem as the range of a particular species of interest, such as the area where wolves roam, or they might define it using topographic features, such as two mountain ranges enclosing a valley.
•How are ecosystem boundaries imposed by humans sometimes different from natural boundaries?
Boundaries imposed by humans may not include all of the land the animals inhabit, therefore the natural boundaries would include all land used by the animals. •Why is photosynthesis an important process?
Photosynthesis is the process by which producers use solar energy to convert carbon dioxide and water into glucose, and they produce the oxygen we need to breathe.
•What determines the productivity of an ecosystem?
Producers in an ecosystem capture solar energy via photosynthesis, gross primary productivity (GPP) measures this over a given amount of time.
•How efficiently is energy transferred between trophic levels in an ecosystem?
Not all of the energy contained in a particular trophic level is in a usable form. Some parts of plants are not digestible and are excreted by primary consumers. Secondary consumers such as owls consume the muscles and organs of their prey, but they cannot digest bones and hair. Of the food that is digestible, some fraction of the energy it contains is used to power the consumer’s day-to-day activities, including moving, eating, and (for birds and mammals) maintaining a constant body temperature. That energy is ultimately lost as heat. Any energy left over may be converted into consumer biomass by growth and reproduction and thus becomes available for consumption by organisms at the next higher trophic level. The proportion of consumed energy that can be passed from one trophic level to another is referred to as ecological efficiency. Vocabulary Vocab •What are the dominant elements that make up living organisms?
carbon, hydrogen, nitrogen, oxygen, and phosphorus
•What role does water play in nutrient cycling?
In the carbon cycle, the excess carbon is absorbed by the ocean.
In the nitrogen cycle, nitrogen is transported by water.
In the phosphorus cycle, excess phosphorus can be absorbed by oceans and streams by runoff water.
•What are the main similarities and differences among the carbon,nitrogen, and phosphorus cycles?
All three can be dissolved in water as positively charged ions:Ca2+, Mg2+, and K+. None is present in a gaseous phase, but all can be deposited from the air in small amounts as dust. Because Ca2+ and Mg2+ are strongly attracted to soil particles,they are abundant in many soils overlying these rock types. In contrast, K+ is only weakly attracted to soil particles and is therefore more susceptible to being leached away by water moving through the soil. •Why is Hubbard Brook valuable as a study area? What does it teach us?
It has been studied for over 50 years, and it does is underlain by impenetrable bedrock. All rainwater must leave by evapotranspiration. They conducted a study of how clear cutting would affect rainwater… Within 6 months after the cutting, the clear-cut watershed showed significant increases in stream nitrate concentrations. With this information, the researchers were able to determine that when trees are no longer present to take up nitrate from the soil, nitrate leaches out of the soil and ends up in the stream that drains the watershed.
•What is the difference between resistance and resilience in an ecosystem?
Resistance is a measure of how much a disturbance can affect flows of energy and matter in an ecosystem. Resilience is the rate at which an ecosystem returns to normal after a disturbance.
•What is the intermediate disturbance hypothesis?
The intermediate disturbance hypothesis states ecosystems experiencing intermediate levels of disturbance are more diverse than those with high or low disturbance levels. •What factors go into calculating the instrumental value of an ecosystem?
Economic benefit or instrumental values
•What are the five categories of ecosystem services?
provisions, regulating services, support systems, resilience, and cultural services.
•How do the instrumental and intrinsic values of ecosystems differ?
Instrumental value means we use the animal or land for money, pharmaceutical purposes etc, intrinsic values would mean we protect it because it is right. Ecosystem: A particular location on Earth distinguished by its mix of interacting biotic and abiotic components. Decomposers: Fungi or bacteria that recycle nutrients from dead tissues and wastes back into an ecosystem. Producer/Autotroph: An organism that uses the energy of the Sun to produce usable forms of energy. Photosynthesis: The process by which producers use solar energy to convert carbon dioxide and water into glucose Cellular respiration: The process by which cells convert glucose and oxygen into energy, carbon dioxide, and water Consumer/Heterotorph: An organism that must obtain its energy by consuming other organisms. Primary consumer: An individual incapable of photosynthesis; must obtain energy by consuming other organisms. Secondary consumer: A carnivore that eats primary consumers. Tertiary consumer: A carnivore that eats secondary consumers. Trophic levels: Levels in the feeding structure of organisms. Higher trophic levels consume organisms from lower levels. Food chain: The sequence of consumption from producers through tertiary consumers. Food web: A complex model of how energy and matter move between trophic levels. Scavenger: A carnivore that consumes dead animals. Detritivore: An organism that specializes in breaking down dead tissues and waste products into smaller particles. Gross primary productivity (GPP): The total amount of solar energy that producers in an ecosystem capture via photosynthesis over a given amount of time. Net primary productivity (NPP): The energy captured by producers in an ecosystem minus the energy producers respire. Standing crop: The amount of biomass present in an ecosystem at a particular time. Ecological efficiency: The proportion of consumed energy that can be passed from one trophic level to another. Trophic pyramid: A representation of the distribution of biomass, numbers, or energy among trophic levels. Biogeochemical cycles: The movements of matter within and between ecosystems. Hydrologic cycle: The movement of water through the biosphere. Transpiration: The release of water from leaves during photosynthesis. Evapotranspiration: The combined amount of evaporation and transpiration. Runoff: Water that moves across the land surface and into streams and rivers. Macronutrients: The six key elements that organisms need in relatively large amounts: nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. Limiting nutrient: A nutrient required for the growth of an organism but available in a lower quantity than other nutrients. Nitrogen fixation: A process by which some organisms can convert nitrogen gas molecules directly into ammonia. Leaching: The transportation of dissolved molecules through the soil via groundwater Disturbance: An event, caused by physical, chemical, or biological agents, resulting in changes in population size or community composition. Watershed: All land in a given landscape that drains into a particular stream, river, lake, or wetland. Resistance: A measure of how much a disturbance can affect flows of energy and matter in an ecosystem. Resilience: The rate at which an ecosystem returns to its original state after a disturbance. Restoration ecology: The study and implementation of restoring damaged ecosystems. Intermediate disturbance hypothesis: The hypothesis that ecosystems experiencing intermediate levels of disturbance are more diverse than those with high or low disturbance levels. Instrumental value: Something that has worth as an instrument or a tool that can be used to accomplish a goal. Provision: A good that humans can use directly