net primary productivity

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net primary productivity

biology

Also known as: NPP

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July 1, 2026

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Net primary productivity refers to the rate at which energy is converted into organic substances by photosynthetic or chemosynthetic organisms, after accounting for the energy producers use for their own life processes. This remaining organic material is then available to support consumers like herbivores and carnivores.12

In marine environments, this productivity is primarily driven by phytoplankton, which are microscopic organisms that float freely in the ocean. Benthic algae, which grow on the ocean floor, contribute a smaller percentage to the total marine plant material. Primary productivity is typically measured by tracking the uptake of carbon dioxide or the output of oxygen, and is expressed in units of organic carbon per area per unit of time. Factors such as light intensity, and the availability of nutrients like nitrogen and phosphorus, significantly influence these production rates.12

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tropical rainforest
Biological productivity
…used by plants is called net primary productivity, and it is this remainder that is available to various consumers in the ecosystem—e.g., the herbivores, decomposers, and carnivores. Of course, in any stable ecosystem there is neither an accumulation nor a diminution in the total amount of organic matter present, so…
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…used by plants is called net primary productivity, and it is this remainder that is available to various consumers in the ecosystem—e.g., the herbivores, decomposers, and carnivores. Of course, in any stable ecosystem there is neither an accumulation nor a diminution in the total amount of organic matter present, so…
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savanna
Biological productivity
…have relatively high levels of net primary productivity compared with the actual biomass (dry mass of organic matter) of the vegetation at any one time. (For a full discussion of productivity, see biosphere: The photosynthetic process.) Most of this productivity is concentrated into the period during and following the wet…
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…have relatively high levels of net primary productivity compared with the actual biomass (dry mass of organic matter) of the vegetation at any one time. (For a full discussion of productivity, see biosphere: The photosynthetic process.) Most of this productivity is concentrated into the period during and following the wet…
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soil
Soils and global warming
…mainly through photosynthesis is called net primary production or NPP and is the dominant source of food, fuel, fibre, and feed for the entire population of Earth. Approximately 55 billion metric tons (61 billion tons) of carbon are stored in this way each year worldwide, most of it in forests.…
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…mainly through photosynthesis is called net primary production or NPP and is the dominant source of food, fuel, fibre, and feed for the entire population of Earth. Approximately 55 billion metric tons (61 billion tons) of carbon are stored in this way each year worldwide, most of it in forests.…
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biosphere
Efficiency of solar energy utilization
…further use and is called net primary productivity. About 40 to 85 percent of gross primary productivity is not used during respiration and becomes net primary productivity. The highest net primary productivity in terrestrial environments occurs in swamps and marshes and tropical rainforests; the lowest occurs in deserts. In aquatic…
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…further use and is called net primary productivity. About 40 to 85 percent of gross primary productivity is not used during respiration and becomes net primary productivity. The highest net primary productivity in terrestrial environments occurs in swamps and marshes and tropical rainforests; the lowest occurs in deserts. In aquatic…
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temperate forest
Biological productivity
Net primary productivity, gross primary productivity less that used by plants in respiration, is approximately 10 metric tons per hectare per year; it is greatest in young forests where the trees are rapidly growing toward full size, and it declines in forests of old trees.…
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Net primary productivity, gross primary productivity less that used by plants in respiration, is approximately 10 metric tons per hectare per year; it is greatest in young forests where the trees are rapidly growing toward full size, and it declines in forests of old trees.…
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