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  2. Primary production - Wikipedia

    en.wikipedia.org/wiki/Primary_production

    Gross primary production (GPP) is the amount of chemical energy, typically expressed as carbon biomass, that primary producers create in a given length of time.Some fraction of this fixed energy is used by primary producers for cellular respiration and maintenance of existing tissues (i.e., "growth respiration" and "maintenance respiration").

  3. Food chain - Wikipedia

    en.wikipedia.org/wiki/Food_chain

    A keystone species is a singular species within an ecosystem that others within the same ecosystem, or the entire ecosystem itself, rely upon. Keystone species' are so vital for an ecosystem that without their presence, an ecosystem could transform or stop existing entirely. [20] One way keystone species impact an ecosystem is through their ...

  4. Trophic level - Wikipedia

    en.wikipedia.org/wiki/Trophic_level

    An exception occurs in deep-sea hydrothermal ecosystems, where there is no sunlight. Here primary producers manufacture food through a process called chemosynthesis. [5] Consumers (heterotrophs) are species that cannot manufacture their own food and need to consume other organisms. Animals that eat primary producers (like plants) are called ...

  5. Ecological pyramid - Wikipedia

    en.wikipedia.org/wiki/Ecological_pyramid

    Two species of comparable biomass may have very different life spans. Thus, a direct comparison of their total biomasses is misleading, but their productivity is directly comparable. The relative energy chain within an ecosystem can be compared using pyramids of energy; also different ecosystems can be compared. There are no inverted pyramids.

  6. Energy flow (ecology) - Wikipedia

    en.wikipedia.org/wiki/Energy_flow_(ecology)

    Species effect and diversity in an ecosystem can be analyzed through their performance and efficiency. [21] In addition, secondary production in streams can be influenced heavily by detritus that falls into the streams; production of benthic fauna biomass and abundance decreased an additional 47–50% during a study of litter removal and exclusion.

  7. Marine food web - Wikipedia

    en.wikipedia.org/wiki/Marine_food_web

    Keystone species are species that have large effects, disproportionate to their numbers, within ecosystem food webs. [157] An ecosystem may experience a dramatic shift if a keystone species is removed, even though that species was a small part of the ecosystem by measures of biomass or productivity . [ 158 ]

  8. Lake ecosystem - Wikipedia

    en.wikipedia.org/wiki/Lake_ecosystem

    At a pH of 5–6 algal species diversity and biomass decrease considerably, leading to an increase in water transparency – a characteristic feature of acidified lakes. As the pH continues lower, all fauna becomes less diverse. The most significant feature is the disruption of fish reproduction.

  9. Ecosystem - Wikipedia

    en.wikipedia.org/wiki/Ecosystem

    Ecologically distinct species, on the other hand, have a much larger effect. Similarly, dominant species have a large effect on ecosystem function, while rare species tend to have a small effect. Keystone species tend to have an effect on ecosystem function that is disproportionate to their abundance in an ecosystem. [11]: 324