- Ecosystems perform essential functions that sustain life on Earth.
- Two primary functions of ecosystems are energy flow and nutrient cycling.
- Energy flow refers to the transfer of energy through different trophic levels in an ecosystem.
- Nutrient cycling involves the recycling of elements like carbon, nitrogen, and phosphorus within the ecosystem.
- Energy flow in an ecosystem is unidirectional, moving from the sun to producers and then to consumers and decomposers.
- Producers capture solar energy through photosynthesis and convert it into chemical energy.
- The energy captured by producers is called gross primary productivity (GPP).
- Net primary productivity (NPP) is the energy available to consumers after producers use some for respiration.
- Consumers obtain energy by feeding on producers or other consumers.
- Decomposers break down organic matter, releasing nutrients back into the ecosystem.
- The trophic levels in an ecosystem are producers, primary consumers, secondary consumers, tertiary consumers, and decomposers.
- Energy transfer between trophic levels is inefficient, with only about 10% of energy passed to the next level.
- This is known as the 10% law of energy transfer, proposed by Raymond Lindeman.
- The loss of energy limits the number of trophic levels in an ecosystem.
- The energy flow can be represented using food chains and food webs.
- A food chain is a linear sequence showing energy transfer from one organism to another.
- A food web is a complex network of interconnected food chains in an ecosystem.
- Nutrient cycling, also known as biogeochemical cycling, maintains the balance of essential elements in ecosystems.
- The carbon cycle involves the exchange of carbon among the atmosphere, organisms, and soil.
- Photosynthesis and respiration are key processes in the carbon cycle.
- The nitrogen cycle converts nitrogen from the atmosphere into forms usable by plants and animals.
- Nitrogen fixation is carried out by certain bacteria, converting atmospheric nitrogen into ammonia.
- The phosphorus cycle moves phosphorus through rocks, water, soil, and living organisms.
- The phosphorus cycle lacks a significant atmospheric component, unlike the carbon and nitrogen cycles.
- The water cycle, or hydrological cycle, involves the movement of water through evaporation, condensation, and precipitation.
- Nutrient cycling ensures the availability of essential nutrients for plants, animals, and microorganisms.
- The interaction between energy flow and nutrient cycling drives ecosystem productivity.
- Human activities, such as deforestation and pollution, disrupt energy flow and nutrient cycling.
- Eutrophication is caused by excessive nutrient runoff, leading to algal blooms and oxygen depletion in water bodies.
- Climate change impacts energy flow and nutrient cycling by altering ecosystem dynamics.
- The efficiency of energy flow and nutrient cycling determines the health of an ecosystem.
- Conservation efforts aim to restore balance in ecosystems by addressing these key functions.
- Understanding energy flow and nutrient cycling helps in sustainable resource management.
- Ecological pyramids represent energy, biomass, or organism numbers across trophic levels.
- An energy pyramid illustrates the reduction of energy at successive trophic levels.
- A biomass pyramid shows the total mass of living organisms at each trophic level.
- A number pyramid represents the number of organisms at each trophic level.
- Energy flow and nutrient cycling are influenced by climatic and geological factors.
- The efficiency of energy flow is higher in ecosystems with shorter food chains.
- Ecosystems with diverse biodiversity tend to have more stable energy flow and nutrient cycles.
- Decomposers play a vital role in maintaining nutrient cycling by breaking down organic matter.
- Efforts to reduce waste and recycle materials align with the principles of nutrient cycling.
- Energy flow and nutrient cycling are interconnected, supporting life processes in ecosystems.
- Disruptions in these processes can lead to ecosystem degradation and biodiversity loss.
- The study of these functions is crucial for addressing environmental challenges and promoting sustainability.