Food Web
A food web shows feeding connections in an ecological community. There are two main trophic levels: autotrophs and heterotrophs. The links in a food web illustrate the feeding pathways, such as where heterotrophs obtain organic matter by feeding on autotrophs and other heterotrophs. The food web is a simplified illustration of the various methods of feeding that links an ecosystem into a unified system of exchange. There are different kinds of feeding relations that can be roughly divided into herbivores, carnivores, and scavengers. Some of the organic matter eaten by heterotrophs, such as sugars, provides energy.
Autotrophs produce more biomass energy, either chemically without the suns energy or by capturing the suns energy in photosynthesis, than they use during metabolic respiration. Heterotrophs consume rather than produce biomass energy as they metabolize, grow, and add to levels of secondary production.
A food web depicts a collection of heterotrophic consumers that cycle the energy and nutrients from a productive base of self-feeding autotrophs. The base species in a food web are those species without prey and can include autotrophs or saprophytic detritivores. Feeding connections in the web are called trophic links. The number of trophic links per consumer is a measure of food web connectance. Food chains are nested within the trophic links of food webs. Food chains are nested within the trophic links of food webs.
A food web shows feeding connections in an ecological community. There are two main trophic levels: autotrophs and heterotrophs. The links in a food web illustrate the feeding pathways, such as where heterotrophs obtain organic matter by feeding on autotrophs and other heterotrophs. The food web is a simplified illustration of the various methods of feeding that links an ecosystem into a unified system of exchange. There are different kinds of feeding relations that can be roughly divided into herbivores, carnivores, and scavengers. Some of the organic matter eaten by heterotrophs, such as sugars, provides energy.
Autotrophs produce more biomass energy, either chemically without the suns energy or by capturing the suns energy in photosynthesis, than they use during metabolic respiration. Heterotrophs consume rather than produce biomass energy as they metabolize, grow, and add to levels of secondary production.
A food web depicts a collection of heterotrophic consumers that cycle the energy and nutrients from a productive base of self-feeding autotrophs. The base species in a food web are those species without prey and can include autotrophs or saprophytic detritivores. Feeding connections in the web are called trophic links. The number of trophic links per consumer is a measure of food web connectance. Food chains are nested within the trophic links of food webs. Food chains are nested within the trophic links of food webs.
This
is a food web where krill is an essential food source to almost all of the
organisms. If I were t eliminate krill from the food web there would be a lot
of consequences. Most animals would have to eat either another organisms or
just go extinct. The phytoplankton would reproduce a lot faster and expand in
size.
Food Pyramid
In a pyramid of numbers, the number of consumers at each level decreases significantly, so that a single top consumer will be supported by a much larger number of separate producers. There is usually a maximum of four or five links in an energy pyramid. Eventually, all the energy in an energy pyramid is dispersed as heat.
Energy pyramid structures can vary across ecosystems and across time. In some instances biomass pyramids can be inverted. This pattern is often identified in aquatic and coral reef ecosystems. The pattern of biomass inversion is attributed to different sizes of producers. Aquatic communities are often dominated by producers that are smaller than the consumers that have high growth rates. Producers such as planktonic algae. However, they are able to reproduce quickly enough to support a larger biomass of grazers. Phytoplankton live just a few days, whereas the zooplankton eating the phytoplankton live for several weeks and the fish eating the zooplankton live for several consecutive years. Primary consumers have longer life spans and slower growth rates that accumulate more biomass than the producers they consume. Aquatic predators also tend to have a lower death rate than the smaller consumers, which contributes to the inverted pyramidal pattern. Energy pyramids will always have an upright pyramid shape if all sources of food energy are included.
In a pyramid of numbers, the number of consumers at each level decreases significantly, so that a single top consumer will be supported by a much larger number of separate producers. There is usually a maximum of four or five links in an energy pyramid. Eventually, all the energy in an energy pyramid is dispersed as heat.
Energy pyramid structures can vary across ecosystems and across time. In some instances biomass pyramids can be inverted. This pattern is often identified in aquatic and coral reef ecosystems. The pattern of biomass inversion is attributed to different sizes of producers. Aquatic communities are often dominated by producers that are smaller than the consumers that have high growth rates. Producers such as planktonic algae. However, they are able to reproduce quickly enough to support a larger biomass of grazers. Phytoplankton live just a few days, whereas the zooplankton eating the phytoplankton live for several weeks and the fish eating the zooplankton live for several consecutive years. Primary consumers have longer life spans and slower growth rates that accumulate more biomass than the producers they consume. Aquatic predators also tend to have a lower death rate than the smaller consumers, which contributes to the inverted pyramidal pattern. Energy pyramids will always have an upright pyramid shape if all sources of food energy are included.
In
an ocean surface energy pyramid would go from phytoplankton to zoo plankton to
small nekton to large nekton to top predators to detritus. An energy pyramid moves from the producer to
consumers to decomposers.
Alexis's notes.
Jennifer typed it.
Jennifer typed it.