Energy in an ecosystem

Pyramid of biomass --Ecosystems: Productivity and Efficiency

A pyramid of biomass represents the amount of energy contained in biomass at different trophic levels for a particular time. The lower level determines how much energy will be available to the upper level. And since energy is lost in transfer, there is less energy higher up the pyramid.

Pyramid of numbers

A pyramid of numbers represents the number of organisms in each trophic level. This pyramid consists of a plot of relationships between the number of primary consumers, secondary consumers, tertiary consumers, and so forth.

pyramid of productivity

A pyramid of productivity illustrates productivity consumed compared to productivity acquired, showing the flow of energy through the food chain.

Which statement is correct?

All organisms that cannot synthesize their food by means of photosynthesis or chemosynthesis are heterotrophic.

Which is the most accurate description of an ecosystem?

An ecosystem consists of a biological community—the physical and chemical factors—that make up its abiotic environment.

Ecosystem --Flow of energy in an ecosystem

An ecosystem is a community where living and nonliving components actively interact with one another and thrive. The single thread that holds an ecosystem together is energy because all living things need energy to survive. The energy flow within an ecosystem determines what lives and what dies.

Review

An ecosystem is the interaction between its living and nonliving elements. Ecosystems can be as small as a puddle of water or as large as the Sahara Desert. Energy flow and chemical cycling are the main processes that keep an ecosystem alive. The flow of energy originates from the sun and travels from one trophic level to the next through food chains and food webs. Biomass, number, and productivity pyramids are ways of showing the loss of energy that occurs between trophic levels. The five basic trophic levels are the primary producers, or autotrophs, at level one; then the primary consumers (herbivores), secondary consumers (carnivores that eat herbivores), and tertiary consumers (carnivores that eat other carnivores); and finally the detritivores, or decomposers, such as bacteria and fungi, at level five.

Loss of Energy at Each Trophic Level continue

As the sun's energy enters an ecosystem, it is first captured through the process of photosynthesis, with energy loss occurring as it moves through the ecosystem. The energy in an ecosystem can be measured and recorded in the form of biomass. Here are some points to keep in mind about biomass: --The term biomass refers to the total mass of all organisms, plants, and animals in an ecosystem. --Biomass production is the amount of biomass produced for a given amount of solar energy. --By recording the mass of each producer and consumer, a biomass pyramid can be created. --The amount of biomass decreases as you move up the pyramid. Biomass of the producers is always greater than that of the consumers.

A scientist found a new bacteria in a hot water sulfur spring that uses sulfur as a source of energy instead sunlight. What kind of organism could it be?

Chemosynthetic

Loss of Energy at Each Trophic Level

Energy enters an ecosystem in the form of sunlight. This energy is used up and lost as heat as it moves through the ecosystem. Autotrophs, such as plants and algae, convert this energy into chemical energy, or biomass. Some of this energy is stored in the organic compounds of food and then passed on to heterotrophs (creatures that must ingest biomass to obtain energy and nutrition) while the rest is released in the form of heat. As energy passes from trophic level to trophic level, only a fraction of the energy available at one trophic level is transferred to the next trophic level. The amount of energy available to a trophic level depends on the amount of energy stored by the level just below it. Total energy decreases as you move up the trophic levels. Because less energy is available at the higher trophic levels, the total biomass at these levels is also less than at the lower levels.

Which trophic level does a fish represent in this food chain? algae → mosquito larva → dragonfly larva → fish → man

Not secondary consumer

What kind of pyramid of numbers and pyramid of biomass will be formed in a forest with 75 tigers, 5,000 deer, and 1,00,000 trees?

Not: Both pyramids will be inverted.

Loss of Energy at Each Trophic Level continue

The dry weight or mass of biomass, which is comprised primarily of organic material, can be calculated to create a biomass pyramid. Since all organisms consume more biomass than they contain, charting these levels forms a typical pyramid structure. Not all biomass is passed to a higher trophic level from the lower levels. That is because energy lost to heat in respiration is truly lost to the ecosystem and not all biomass consumed can be used by the consumer; some of it is indigestible and passes out as waste. Some of the energy contained in the waste is consumed by decomposers and returns to the ecosystem, but some is lost. In general, only 10 percent of the energy consumed at a particular trophic level is available to the next trophic level; the rest is lost through the processes described above.

Primary Production

The energy that enters the environment through the sun is converted into carbon dioxide and sugar through the chemical process of photosynthesis. Primary production takes place through photosynthesis. All life on Earth, directly or indirectly, relies on primary production. What is primary production? Primary production of an ecosystem is the amount of light energy converted into chemical energy by autotrophs during a given time period. Autotrophs are organisms that can use photosynthesis and simple forms of carbon and nitrogen to produce organic compounds like sugars, fats, and proteins. So, primary production is the generation of biomass through photosynthesis. The rate at which this energy accumulates is called primary productivity.

Food chain

Trophic relationships determine how energy flows through an ecosystem. All living things need food to survive. Organisms at different levels feed on each other in a specific sequence. This feeding relationship between organisms is called a food chain. Different food chains cross-link to form a food web. In other words, the relationships between food chains and food webs form a complex combination of prey and predators, scavengers, decomposers, and organisms that are interwoven together. Each role played by any specific organism is very important to the survival of the ecosystem.

Carbon Cycle and Nitrogen Cycle

Two chemical processes take place during the functioning of an ecosystem—the carbon cycle and the nitrogen cycle. How do you think carbon and nitrogen are cycled through the abiotic and biotic components of an ecosystem? Remember that abiotic components are not related to living organisms. Sunlight, temperature, and precipitation are abiotic components. Biotic components, on the other hand, are living organisms.

In what pattern does the flow of energy in the ecosystem take place?

Unidirectional

Which is a correct example of a food chain?

sun → rice → mouse → cobra → hawk