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In ecology, the trophic level (Greek trophē, food) is the position that an organism occupies in a food chain - what it eats, and what eats it. Ernst Haeckel coined the term oekologie in 1866. ...
Food chains and food webs and/or food networks describe the feeding relationships between species in a biotic community. ...
Energy economy
 An arctic food web. Each arrow represents an increase in trophic level. Wildlife biologists look at a natural "economy of energy" that ultimately rests upon solar energy. When they look at an ecosystem there is always some foundation species that directly harvests energy from the sun, for example, grass (however in deep sea hydrothermal vents chemosynthetic archaea form the base of the food chain). Next are herbivores (primary consumers) that eat the grass, such as the rabbit. Next are carnivores (secondary consumers) that eat the rabbit, such as a bobcat. An example of a foodweb diagram; drawn myself. ...
An example of a foodweb diagram; drawn myself. ...
The red line indicates the 10°C isotherm in July, commonly used to define the Arctic region border Satellite image of the Arctic surface The Arctic is the area around the Earths North Pole, opposite the Antarctican area around the South Pole. ...
Various species of deer are commonly seen wildlife across the Americas and Eurasia. ...
A biologist is a scientist devoted to and producing results in biology through the study of organisms. ...
Energy economics is a subfield of economics that focuses on energy relationships as the foundation of all other relationships. ...
An ecosystem, a contraction of ecological and system, refers to the collection of components and processes that comprise, and govern the behavior of, some defined subset of the biosphere. ...
A foundation species is a dominant primary producer in an ecosystem both in terms of abundance and influence. ...
A hydrothermal vent A hydrothermal vent is a fissure in a planets surface from which geothermally heated water issues. ...
Chemosynthesis is the biological conversion of 1-carbon molecules (usually carbon dioxide or methane) and nutrients into organic matter using the oxidation of inorganic molecules (e. ...
Phyla / Classes Phylum Crenarchaeota Phylum Euryarchaeota Halobacteria Methanobacteria Methanococci Methanopyri Archaeoglobi Thermoplasmata Thermococci Phylum Korarchaeota Phylum Nanoarchaeota Archaea (; from Greek αÏχαία, ancient ones; singular Archaeum, Archaean, or Archaeon), also called Archaebacteria (), is a major division of living organisms. ...
A deer and two fawns feeding on some foliage A herbivore is often defined as any organism that eats only plants[1]. By that definition, many fungi, some bacteria, many animals, about 1% of flowering plants and some protists can be considered herbivores. ...
This tigers sharp teeth and strong jaws are the classical physical traits expected from carnivorous mammalian predators A carnivore (IPA: ), meaning meat eater (Latin carne meaning flesh and vorare meaning to devour), is an animal that eats a diet consisting mainly of meat, whether it comes from live animals...
There can be several intermediate links, which means that there can be another layer of predators on top, such as mountain lions, which sometimes eat bobcats. Since each layer of this system relates to the one below it by absorbing a fraction of the energy it consumed, each one can be understood as resting on the one below -- which is called a lower trophic level.
Keep in mind that trophic relationships are rarely this simple. Very often they are more of a "web" than a "chain." For example, the mountain lion may eat the bobcat, but it also eats rabbits. The trophic categorization of the mountain lion exists on two levels, possibly more. Food chains and food webs and/or food networks describe the feeding relationships between species in a biotic community. ...
Food chains and food webs and/or food networks describe the feeding relationships between species in a biotic community. ...
Every time there is an exchange of energy between one trophic level and another, there is a quite significant loss due to the fundamental laws of thermodynamics. This means so many units of grass can only support a much smaller number of units of rabbits, who can only support a smaller group of bobcats, who can only support a smaller group of mountain lions. This is why trophic levels are usually portrayed as a triangle, one that places grass on the bottom and mountain lions on top---the top is always much smaller than the bottom. Each level implies a loss of energy and efficiency and less life that can be supported by the sun. Thermodynamics (from the Greek thermos meaning heat and dynamics meaning power) is a branch of physics that studies the effects of changes in temperature, pressure, and volume on physical systems at the macroscopic scale by analyzing the collective motion of their particles using statistics. ...
Components of ecosystems Ecosystems have four basic components: An ecosystem, a contraction of ecological and system, refers to the collection of components and processes that comprise, and govern the behavior of, some defined subset of the biosphere. ...
- The abiotic environment
- Producers
- Consumers
- Decomposers
Producers (autotrophs) utilize energy from the sun and nutrients from the abiotic environment (carbon dioxide from the air or water, other nutrients from the soil or water) to perform photosynthesis and grow. Producers are generally green plants (those with chlorophyll). See carbon cycle for more on carbon's role. Green (from chlorophyll) fronds of a maidenhair fern: a photoautotroph Flowchart to determine if a species is autotroph, heterotroph, or a subtype An autotroph (from the Greek autos = self and trophe = nutrition) is an organism that produces organic compounds from carbon dioxide as a carbon source, using either light or...
Carbon dioxide is a chemical compound composed of one carbon and two oxygen atoms. ...
The leaf is the primary site of photosynthesis in plants. ...
Chlorophyll gives leaves their green color Space-filling model of the chlorophyll molecule Chlorophyll is a green photosynthetic pigment found in most plants, algae, and cyanobacteria. ...
The carbon cycle is the biogeochemical cycle by which carbon is exchanged between the biosphere, geosphere, hydrosphere and atmosphere of the Earth (other astronomical objects may have similar carbon cycles, but nothing is yet known about them). ...
Consumers (heterotrophs) are organisms that feed on other organisms. Flowchart to determine if a species is autotroph, heterotroph, or a subtype A heterotroph (Greek heterone = (an)other and trophe = nutrtion) is an organism that requires organic substrates to get its carbon for growth and development. ...
Decomposers and Detritivores utilize energy from wastes or dead organisms, and so complete the cycle by returning nutrients to the soil or water, and carbon dioxide to the air and water. See water cycle for more on water's role. The fungi on the tree are decomposers. ...
A dung beetle rolling a ball of dung Detritivores (also known as saprophages, detrivores or detritus feeders) are organisms that recycle detritus (decomposing organic material), returning it into the food chain. ...
Waste inside a wheelie bin Waste, rubbish, trash, garbage, or junk is unwanted or undesired material. ...
The movement of water around, over, and through the Earth is called the water cycle. ...
Biomass production Primary production is generation of biomass through photosynthesis. The highest producers of biomass are |0. ...
Others include ...
A freshwater swamp This article is about the wetland type (a landform). ...
A seaweed (Laurencia) up close: the branches are multicellular and only about 1 mm thick. ...
Some of the biodiversity of a coral reef. ...
Estuaries and coastal waters are among the most productive ecosystems on Earth, providing ecological, economic, cultural, and aesthetic benefits. ...
while lowest producers are deserts and frozen areas (less than 200 g/m2/yr of biomass). Temperate forests are forests in the temperate climate zones. ...
Agriculture (a term which encompasses farming) is the process of producing food, feed, fiber and other goods by the systematic raising of plants and animals. ...
Erg Chebbi, Morocco In geography, a desert is a landscape form or region that receives very little precipitation. ...
In physical geography, tundra is an area where the tree growth is hindered by low temperatures and short growing seasons. ...
In the ocean, phytoplankton is the primary producer (the first level in the food chain or the first trophic level).Phytoplankton converts inorganic carbon into protoplasm.
Phytoplankton is consumed by microscopic animals called zooplankton (these are the second level in the food chain).
Zooplankton is consumed by Crustaceans (the third level in the food chain).
Fish that eat crustaceans could constitute the fourth trophic level, while seals consuming the fishes are the fifth.
Trophic levels are very similar on land, with plants being the first trophic level, cows eating the grass being the second, and humans eating the cows being the third. Diagrams of some typical phytoplankton Phytoplankton are the autotrophic component of the plankton that drift in the water column. ...
The term primary producer (or autotroph) describes a trophic level in an ecosystem that includes all organisms which make their own food. ...
Food chains and food webs and/or food networks describe the feeding relationships between species in a biotic community. ...
In biology, protoplasm is the living substance inside the cell. ...
Photomontage of plankton organisms Plankton is the aggregate community of weakly swimming but mostly drifting small organisms that inhabit the water column of the ocean, seas, and bodies of freshwater. ...
Classes & Subclasses Branchiopoda Phyllopoda Sarsostraca Remipedia Cephalocarida Maxillopoda Thecostraca Tantulocarida Branchiura Pentastomida Mystacocarida Copepoda Ostracoda Myodocopa Podocopa Malacostraca Phyllocarida Hoplocarida Eumalacostraca The crustaceans (Crustacea) are a large group of arthropods, comprising approximately 52,000 described species [1], and are usually treated as a subphylum [2].They include various familiar animals...
The amount of biomass produced for a given amount of solar energy is highest at the first level. Less biomass is produced at the second level, for some energy is lost during the conversion. The more trophic levels there are, the more energy is lost through conversion.
Humans are generally primary and secondary consumers, and thus represent usually second and third trophic levels. Most humans are omnivores, which means they consume both plants and animals. When referring to omnivore from an ecological standpoint it means to consume from different trophic levels. Less energy is required to support vegetarian humans than omnivorous ones, for there is a significant energy loss during the conversion of grain and vegetables in animal matter. Pigs are omnivores. ...
For animals adapted to eat primarily plants, sometimes referred to as vegetarian animals, see Herbivore. ...
Trophic levels and biodiversity Each species in an ecosystem is affected by the other species in that ecosystem. There are very few single prey-single predator relationships. Most preys are consumed by more than one predator, and most predators have more than one prey. Their relationships are also influenced by other environmental factors. In biology, a species is one of the basic units of biodiversity. ...
An ecosystem, a contraction of ecological and system, refers to the collection of components and processes that comprise, and govern the behavior of, some defined subset of the biosphere. ...
Biodiversity (seen from the viewpoint of species diversity) is a major contributor to the stability of ecosystems. When an organism can exploit a wide range of resources, a decrease in biodiversity is less likely to have an impact. However, for an organism which can only exploit a limited range of resources, a decrease in biodiversity is more likely to have a strong effect. David Tilman is an ecologist who has done a lot of work establishing the theoretical basis of this phenomenon. Rainforests are among the most biodiverse ecosystems on earth Biodiversity or biological diversity is the diversity of life. ...
Reduction of habitat, hunting and fishing of some species to extinction or near extinction, and eradication of insects and pollution tend to tip the balance of biodiversity. Similarly, in-situ conservation areas need to be carefully designed to maintain a diverse and stable environnement for the extinct species to thrive. The Dodo, shown here in illustration, is an often-cited[1] example of extinction. ...
Rainforests are among the most biodiverse ecosystems on earth Biodiversity or biological diversity is the diversity of life. ...
The conservation ethic is an ethic of resource use, allocation, exploitation, and protection. ...
For a systematic treatment of biodiversity within a trophic level, see unified neutral theory of biodiversity. The unified neutral theory of biodiversity and biogeography (here Unified Theory or UNTB) is a theory and the title of a monograph[1] by ecologist Stephen Hubbell. ...
Multitrophic interactions Trophic interactions can involve more than the two players "predator" and "prey". When more than two trophic level are involved, we talk of "multitrophic interactions" or "multitrophic level interactions". The multitrophic approach has consciously entered ecological sciences with a review paper published by six authors in 1980 (Price et al., 1980, Interactions among three trophic levels: influence of plants on interactions between insect herbivores and natural enemies). The paper expands the classical plant-herbivore system to the three-tier system plant-herbivore-natural enemies of plant herbivores. The authors say: "We argue that theory on insect-plant interactions cannot progress realistically without consideration of the third trophic level." To date (December 2005) the paper is cited 794 times (Web of Science). The field of multitrophic level interactions has become important especially since the mid 1990s. Image File history File links Information_icon. ...
A recent book offers a synthesis of this topic: Tscharntke, T., Hawkins, B., A., (eds), 2002: Multitrophic Level Interactions, Cambridge University Press, Cambridge.
Trophic levels and evolutionary theory A compelling sidenote to the discussion of trophic levels is the incongruence of low-level trophic efficiency and the upward trophic movement of species described in evolutionary theory.
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