What Does The Biological Term “Net Primary Production” Mean?

Productivity in ecology refers to the rate of biomass generation, energy addition, carbon fixation, and organic matter addition. Primary productivity (NPP) is the rate at which energy is converted to organic substances by photosynthetic producers (photoautotrophs). Net primary productivity (NPP) is the “useful” GPP left over, calculated using mass / area / time – mass of carbon per unit area per year (g C m −2 yr −1). It is approximately 10 metric tons per hectare per year and is greatest in young forests.

NPP is the rate at which all plants in an ecosystem produce net useful chemical energy, minus the energy they use during metabolic processes such as respiration. It is calculated primarily by an increase in biomass in a unit time per unit area. Net primary productivity is the difference between the energy fixed by autotrophs and their own respiration losses. It refers to the amount of energy available to herbivores in the plant’s biomass after plant respiratory losses.

In summary, productivity refers to the rate at which all plants in an ecosystem produce net useful chemical energy, with net primary production (NPP) being the “useful” GPP left over. It is calculated using mass / area / time – mass of carbon per unit area per year.

What does npp mean?

Net Primary Productivity (NPP) represents the quantity of energy captured by plants during the process of photosynthesis, with the loss of energy through respiration being subtracted. This concept is fundamental to the fields of ecology and environmental science.

What is npp, GPP, and r?

GPP (Graded Primary Productivity), NPP (Net Primary Productivity), and R (Respiration loss) are key metrics in ecosystem analysis. Net primary productivity is the energy stored by autotrophs after subtracting carbon lost in respiration. NPP (Physical Respiration) measures the overall efficiency of plants in the ecosystem. GPP (Photosynthesis Rate) refers to the rate of energy stored by plants, while R (Respiration loss) represents the rate of energy loss.

The R f (Relative Front or Retardation Factor) value represents the ratio of the distance traveled by the solute to the solvent in a solution. Environmental factors, such as temperature, food, pollutants, population density, sound, light, and parasites, can affect living organisms and cause adverse health effects like skin diseases, oxygen loss, and respiratory problems.

What does NPP stand for in biology?

Net primary production (NPP) is the amount of biomass or carbon produced by primary producers per unit area and time, calculated by subtracting plant respiratory costs from gross primary productivity (GPP) or total photosynthesis. Net ecosystem production (NEP) expresses net carbon accumulation by ecosystems, obtained by subtracting the respiratory costs of all organisms (Rall), including plants, grazers, and microbes, from GPP. When NEP is positive, there is a net gain of carbon in the ecosystem.

Examples of extreme topsoil erosion in Iceland and Kruger National Park South Africa demonstrate the impact of these factors on NPP. In Iceland, thick Andosoils have been removed by wind and water, leaving shallow and poor soils with limited vegetation cover. In Kruger National Park South Africa, a flux tower measures the breathing of an African savanna ecosystem, revealing that CO2 is taken up by vegetation during summer days, leading to increased biomass. This system’s long-term equilibrium and carbon store are crucial in climate change contexts.

What does NPP do?

Nandrolone phenylpropionate (NPP), also known as Durabolin, is an androgen and anabolic steroid (AAS) medication used primarily for treating breast cancer and osteoporosis in women. It is given by injection into muscle once every week. Despite its widespread use, NPP has mostly been discontinued and is no longer available. Its side effects include symptoms of masculinization, increased hair growth, voice changes, and increased sexual desire. NPP is a synthetic androgen and anabolic steroid, acting as an agonist of the androgen receptor (AR), the biological target of androgens like testosterone and dihydrotestosterone (DHT).

It has strong anabolic effects and weak androgenic effects, making it suitable for use in women and children. NPP was first described in 1957 and introduced for medical use in 1959. It was the first nandrolone ester to be introduced, followed by nandrolone decanoate in 1962. NPP has been largely superseded by nandrolone decanoate, which is longer-acting and more convenient to use. In addition to its medical use, NPP is used to improve physique and performance. However, the drug is a controlled substance in many countries, making non-medical use generally illicit.

What is the lowest mean net primary productivity?

The most appropriate response to the question posed in the UPPSC Civil Services (Prelims) Exam GS Official Paper-I is “temperate grasslands.” This is the most prevalent type of vegetation observed in tropical forests.

What does the NPP represent?

Primary productivity, the process of plant photosynthetic activity, determines biomass accumulation in forests. Net primary productivity (NPP) represents the difference between gross photosynthesis of plant foliage and energy losses due to respiration and mortality of plant tissues. The rate of biomass accumulation during transient ecosystem development depends on forest NPP, and understanding the factors constraining NPP and how they may be affected by forest management and environmental change is crucial.

In the context of the Hubbard Brook ecosystem, current understanding of forest biomass and NPP includes current measurement techniques, patterns of temporal and spatial variation, environmental and biotic factors causing this variation, and implications for responses to global and regional environmental change. Direct measurement of biomass is impractical in forests, so indirect approaches have been developed, relying on allometric relationships between plant dimensions and aboveground biomass.

At Hubbard Brook, Whittaker et al. measured the dimensions of 93 trees of different species and sites, developed allometric equations relating biomass to diameter and height, and calculated forest biomass using species-specific allometric equations. Monte Carlo approaches can also be used to determine the statistical uncertainty of aboveground biomass estimates.

What is the difference between NPP and GPP?

Net primary productivity (NPP) represents the rate at which all plants in an ecosystem produce net useful chemical energy. In contrast, gross primary productivity (GPP) denotes the rate at which primary producers save and collect biomass for energy conservation.

What does high NPP mean?

Net primary productivity (NPP) is directly related to ecosystem conditions, with favorable conditions indicating plant growth. The biosphere, a vast array of diverse, interconnected organisms, is crucial for life and oxygen release. It is divided into biomes based on location, climate, structure, and composition, such as tropical forests, savannas, and agriculture. Within each biome are many smaller ecosystems, each with its own functional roles.

The biosphere is considered the global ecosystem, with organisms occupying various niches. Conservation of energy and the fundamental processes of photosynthesis and primary production are common features among ecosystems. Plants use solar energy to convert carbon dioxide and water into carbohydrates through photosynthesis, which involves the absorption of light by chlorophyll pigments found in virtually all plants. This process, which is crucial for plant growth, is observed in both terrestrial and aquatic ecosystems.

What causes high net primary productivity?

Primary producers depend on nitrogen and phosphorus, which are found in soil, lakes, rivers, and oceans as nitrate, nitrite, ammonia, and phosphorus. The abundance of these molecules and the quality of light exert a considerable influence on production rates.

What is NPP in simple terms?

Net primary production (NPP) is the difference between the energy fixed by autotrophs and their respiration, often equated to increments in biomass per unit of land surface and time. It is commonly equated to biomass per unit of land surface and time. Copyright © 2024 Elsevier B. V., its licensors, and contributors. All rights reserved, including those for text and data mining, AI training, and similar technologies.

What does NPP measure?

NPP is the net carbon gain by plants, balancing the carbon gained by gross primary production (GPP) and released by plant mitochondrial respiration per unit land area. It is expressed per unit land area. ScienceDirect uses cookies and all rights are reserved, including those for text and data mining, AI training, and similar technologies. Open access content is licensed under Creative Commons terms.