c4.2 energy transfer

Matter recycling

Matter can be rearranged and reused within ecosystems through biogeochemical cycles.

Energy flow

Energy flows unidirectionally in ecosystems and requires continuous input, primarily from the sun.

Biogeochemical cycles

Natural processes that recycle nutrients in various chemical forms from the nonliving environment to living organisms and back.

Thermodynamics

The branch of physics that deals with the relations between heat and other forms of energy.

Photoautotrophs

Organisms that capture light energy and convert it into chemical energy stored in organic compounds.

Photosynthesis

The process by which photoautotrophs synthesize organic molecules using light energy.

ATP

Adenosine triphosphate, the primary energy currency of cells.

Carbon fertilization effect

The increased rates of photosynthesis in some plant species due to elevated levels of carbon dioxide.

Ocean acidification

The process by which carbon dioxide dissolved in seawater forms carbonic acid, affecting marine ecosystems.

Global warming

An increase in Earth's average surface temperature due to rising levels of greenhouse gases.

Ecosystem

A community of living organisms interacting with their non-living physical environment.

Open system

A system that exchanges both matter and energy with its surroundings.

Closed system

A system that exchanges energy but not matter with its surroundings.

Trophic levels

The levels in a food chain or food web representing different layers of energy flow, from producers to apex predators.

Food chain

A linear sequence showing how energy is transferred from one organism to another through feeding.

Producers

Organisms that produce their own food using an external energy source.

Consumers

Organisms that obtain energy by feeding on other organisms.

Apex predator

The organism at the top of the food chain with no natural predators.

Energy pyramid

A graphical representation of the energy flow in a food chain, typically with a broad base and narrowing apex.

Decomposers

Organisms that break down dead organic matter and waste, recycling nutrients back into the ecosystem.

Autotroph

Organisms that can produce their own food from simple inorganic substances using energy from light or chemical reactions.

Carbon fixation

The process by which inorganic carbon is converted into organic compounds by living organisms.

Heterotroph

Organisms that cannot produce their own food and must obtain energy by consuming organic compounds from other organisms.

Cellular respiration

The process by which organisms break down organic compounds to produce ATP, releasing carbon dioxide and water.

Trophic level identification

Determining the position of an organism in a food chain based on its feeding relationships.

Gross primary production (GPP)

The total amount of organic matter produced by autotrophs in a specific area and time.

Net primary production (NPP)

The amount of organic matter remaining after autotrophs have used some of the GPP for respiration.

Primary production unit

Typically expressed as grams of carbon per square meter per year or energy per unit area per unit time.

Biomass

The total mass of living organisms in a given area or ecosystem.

Secondary production

The rate at which heterotrophs convert energy from their food into new biomass.

Carbon cycle

The process by which carbon is exchanged between the atmosphere, land, water, and living organisms.

Carbon sequestration

The long-term storage of carbon in natural or artificial carbon sinks.

Combustion

A rapid chemical process that involves the oxidation of organic matter, producing heat and light.

Reactants of combustion

Fuel (organic carbon compound) and oxygen (O2) that react during the combustion process.

Sources of organic fuel

Biomass, peat, coal, oil, and natural gas used in combustion reactions.

Peat formation

The accumulation of partially decomposed plant matter in anaerobic conditions, forming an early stage of coal.

Keeling Curve

A graph showing the annual fluctuation of atmospheric carbon dioxide concentration, often with an increasing long-term trend.

Photosynthesis and respiration interdependence

Both processes form a cycle where products of one serve as reactants for the other.

Eddy covariance towers

Instruments used to estimate the flux of carbon dioxide in different ecosystems.

Nutrient cycling

The process through which nutrients like carbon and nitrogen move through biotic and abiotic components of ecosystems.

Abiotic pool

The non-living part of an ecosystem where nutrients exist in inorganic forms.

Autotrophic uptake

The process by which autotrophs absorb inorganic nutrients from the abiotic environment.

Heterotrophic transfer

The process where consumers obtain organic nutrients by feeding on producers or other consumers.

Release of CO2 in decomposition

The process through which decomposers break down organic matter, returning carbon to the atmosphere.

Element recycling

The process through which chemical elements are reused in different forms throughout ecosystems.

Trace elements for living organisms

Essential elements like potassium, calcium, magnesium, and iron required for biological processes.

Energy losses in trophic levels

The reduction of energy available at higher trophic levels due to consumption inefficiencies, metabolism, and waste.

Thermal expansion

The increase in volume of water as it warms, contributing to sea-level rise.

Nitrogen cycling

The movement and transformation of nitrogen within ecosystems, involving processes like fixation and nitrification.

Phosphorus cycling

The transformation and movement of phosphorus through ecosystems, often limited by its availability in rocks and sediments.

Sustainability of ecosystems

The ability of an ecosystem to maintain its processes and functions over time despite disturbances.

Eutrophication

The process by which nutrient pollution leads to excessive plant growth and decay in aquatic ecosystems, often causing hypoxia.

Species distribution changes

Shifts in the geographic range of species due to climate change or other environmental pressures.

Wildfire frequency increase

The growing incidence of wildfires attributed to climate change factors like drought and high temperatures.

Heat loss in ecosystems

The inevitable loss of heat energy from living organisms during metabolic processes.

Inhibiting trophic levels

The limitations on the number of trophic levels in a food chain due to energy loss at each transfer.

Energy pyramid shape

Pyramidal structure with a broad base at producers and increasingly narrower tiers for consumers.

Resistance to disturbances

The ability of ecosystems to withstand and recover from environmental changes or catastrophic events.

Flux measurement methods

Techniques used to assess the movement and exchange rates of carbon and nutrients within ecosystems.

Carbon sink mechanisms

Processes by which ecosystems absorb and store carbon, contributing to climate regulation.

Carbon source mechanisms

Processes that release carbon into the atmosphere, contributing to climate change.

Oxidation reactions in energy extraction

Reactions in which organic compounds lose electrons, releasing energy during metabolic processes.

Thermodynamic inefficiencies

The principles governing energy transfers that dictate that some energy is always lost as heat.

Photosynthetic carbon uptake

The assimilation of carbon dioxide by plants during photosynthesis, reducing atmospheric concentrations.

Carbon emissions from human activity

The release of carbon dioxide resulting from anthropogenic sources such as fossil fuel combustion.

Photosynthesis role in oxygen production

Photosynthesis produces oxygen as a byproduct, vital for aerobic life forms.

Environmental impact assessments

Evaluations conducted to understand the effects of human activities on ecosystems and biodiversity.

Climate model predictions

Projections about future climate conditions based on current trends and various influencing factors.

Biodiversity in ecosystems

The variety of life in a particular habitat or ecosystem, contributing to its stability and resilience.

Trace element cycling

The recycling and movement of essential trace elements necessary for growth and health in organisms.

Soil nutrient replenishment

The natural process through which nutrients are restored to the soil after being absorbed by plants.

Succession in ecosystems

The progressive replacement of one community by another over time, often following a disturbance.

Global carbon budget

The balance between carbon emissions and carbon sinks, crucial for understanding climate change impacts.

Ecosystem services

The benefits provided by ecosystems to humans, including provisioning, regulating, and cultural services.

Resilience of ecosystems

The capacity of an ecosystem to recover from disturbances or changes, maintaining its functions.

Invasive species effects

The impact of non-native species on local ecosystems, often leading to biodiversity loss and ecosystem disruptions.

Restoration ecology

The study and practice of restoring degraded ecosystems to their original conditions and functions.