Limiting factor
A limiting factor is a variable of a system that causes a noticeable change in output or another measure of a type of system. The limiting factor is in a pyramid shape of organisms going up from the producers to consumers and so on. A factor not limiting over a certain domain of starting conditions may yet be limiting over another domain of starting conditions, including that of the factor.
Overview
The identification of a factor as limiting is possible only in distinction to one or more other factors that are non-limiting. Disciplines differ in their use of the term as to whether they allow the simultaneous existence of more than one limiting factor which (may then be called "co-limiting"), but they all require the existence of at least one non-limiting factor when the terms are used. There are several different possible scenarios of limitation when more than one factor is present. The first scenario, called single limitation occurs when only one factor, the one with maximum demand, limits the System. Serial co-limitation is when one factor has no direct limiting effects on the system, but must be present to increase the limitation of a second factor. A third scenario, independent limitation, occurs when two factors both have limiting effects on the system but work through different mechanisms. Another scenario, synergistic limitation, occurs when both factors contribute to the same limitation mechanism, but in different ways.[1]
In 1905 Frederick Blackman articulated the role of limiting factors as follows: "When a process is conditioned as to its rapidity by several separate factors the rate of the process is limited by the pace of the slowest factor." In terms of the magnitude of a function, he wrote, "When the magnitude of a function is limited by one of a set of possible factors, increase of that factor, and of that one alone, will be found to bring about an increase of the magnitude of the function."[2]
Ecology
In population ecology, a regulating factor, also known as a limiting factor,[3] is something that keeps a population at equilibrium (neither increasing nor decreasing in size over time).[citation needed] Common limiting factor resources are environmental features that limit the growth, abundance, or distribution of an organism or a population of organisms in an ecosystem.[4]: G-11 [5] The concept of limiting factors is based on Liebig's Law of the Minimum, which states that growth is controlled not by the total amount of resources available, but by the scarcest resource. In other words, a factor is limiting if a change in the factor produces increased growth, abundance, or distribution of an organism when other factors necessary to the organism's life do not. Limiting factors may be physical or biological.[4]: 417, 8
Limiting factors are not limited to the condition of the species. Some factors may be increased or reduced based on circumstances. An example of a limiting factor is
Oceanography
In oceanography, a prime example of a limiting factor is a limiting nutrient. Nutrient availability in freshwater and marine environments plays a critical role in determining what organisms survive and thrive. Nutrients are the building blocks of all living organisms, as they support biological activity. They are required to make proteins, DNA, membranes, organelles, and exoskeletons. The major elements that constitute >95% of organic matter mass are carbon, hydrogen, nitrogen, oxygen, sulfur, and phosphorus. Minor elements are iron, manganese, cobalt, zinc and copper. These minor elements are often only present in trace amounts but they are key as co-limiting factors as parts of enzymes, transporters, vitamins and amino acids. Within aquatic environments, nitrogen and phosphorus are leading contenders for most limiting nutrients.
Discovery of the Redfield ratio was a major insight that helped understand the relationship between nutrient availability in seawater and their relative abundance in organisms. Redfield was able to notice elemental consistencies between carbon, nitrogen and phosphorus when looking at larger organisms living in the ocean (C:N:P = 106:16:1).[6] He also observed consistencies in nutrients within the water column; nitrate to phosphate ratio was 16:1. The overarching idea was that the environment fundamentally influences the organisms that grow in it and the growing organisms fundamentally influence the environment. Redfield's opening statement in his 1934 paper explains "It is now well recognized that the growth of plankton in the surface layers of the sea is limited in part by the quantities of phosphate and nitrate available for their use and that the changes in the relative quantities of certain substances in seawater are determined in their relative proportions by biological activity".[7] Deviations from Redfield can be used to infer elemental limitations. Limiting nutrients can be discussed in terms of dissolved nutrients, suspended particles and sinking particles, among others. When discussing dissolved nutrient stoichiometry, large deviations from the original Redfield ratio can determine if an environment is phosphorus limited or nitrogen limited. When discussing suspended particle stoichiometry, higher N:P ratios are noted in oligotrophic waters (environments dominated by cyanobacteria; low latitudes/equator) and lower N:P ratios are noted in nutrient rich ecosystems (environments dominated by diatoms; high latitudes/poles).[8]
Many areas are severely nitrogen limited, but phosphorus limitation has also been observed. In many instances trace metals or co-limitation occur. Co-limitations refer to where two or more nutrients simultaneously limit a process. Pinpointing a single limiting factor can be challenging, as nutrient demand varies between organisms, life cycles, and environmental conditions (e.g. thermal stress can increase demand on nutrients for biological repairs).
Business and technology
AllBusiness.com defines a limiting (constraining) factor as an "item that restricts or limits production or sale of a given product". The examples provided include: "limited machine hours and labor-hours and shortage of materials and skilled labor. Other limiting factors may be cubic feet of display or warehouse space, or working capital."[9] The term is also frequently used in technology literature.[10][11]
The analysis of limiting business factors is part of the
Chemistry
In stoichiometry of a chemical reaction to produce a chemical product, it may be observed or predicted that with amounts supplied in specified proportions, one of the reactants will be consumed by the reaction before the others. The amount of product is thus limited by the supply of this reagent. This limiting reagent determines the theoretical yield of the reaction. The other reactants are said to be non-limiting or in excess. This distinction makes sense only when the chemical equilibrium so favors the products to cause the complete consumption of one of the reactants.
In studies of
See also
- Abiotic component
- Bateman's principle
- Biotic component
- Bottleneck (software)
- Chemical kinetics
- Competition (biology)
- Competitive exclusion principle
- Ecology
- Population ecology
- Resource (biology)
- Shelter
References
- ^ PMID 27936500.
- JSTOR 5285.
- ^ a b Thomas M. Smith., Robert Leo Smith. 2009. Or simply, Limiting factors are things that prevent a population from growing any large. Elements of Ecology. Pearson International Edition. 7th Ed.
- ^ "Limiting factor - Biology-Online Dictionary". 10 November 2019.
- ^ Redfield, A.C. (1958). "The biological control of chemical factors in the environment,"" (PDF). American Scientist.
- ^ Redfield, A.C. (1934). "On the proportions of organic derivatives in seawater and their relation to the composition of plankton" (PDF). James Johnstone Memorial: 176–192.
- ^ Benitez-Nelson, Claudia (2018). "The Building Blocks of Life: From Oceanic to Molecular Scales and Back Again". Youtube. Retrieved 19 February 2023.
- ^ "Business definition for: Limiting (constraining) factor". AllBusiness Business Glossary. Retrieved April 28, 2013.
- ^ Sheriff, A.; Bouchlaghem, D.; El-Hamalawi, A.; Yeomans, S. (2012). "Information Management in UK-Based Architecture and Engineering Organizations: Drivers, Constraining Factors, and Barriers". Journal of Management in Engineering. Vol. 28, no. 2. pp. 170–180.
- .
Further reading
- Raghothama, K. G. & Karthikeyan, A. S. (2005). "Phosphate acquisition", Plant and Soil 274: 37-49.
- Taylor, W. A. (1934). "Significance of extreme or intermittent conditions in distribution of species and management of natural resources, with a restatement of Liebig's Law of the minimum", Ecology 15: 374-379.
- Shelford, V. E. (1952). Paired factors and master factors in environmental relations. Illinois Acad. Sci. Trans., 45: 155-160
- Sundareshwar, P. V., Morris, J. T., Koepfler, E. K., and Fornwalt, B. (2003). "Phosphorus limitation of coastal ecosystem processes", Science 299: 563-565.