What Is the Meaning of Law of Tolerance in Biodiversity
Search: `Shelford`s law of tolerance` in Oxford Reference A law which states that the abundance or distribution of an organism may be controlled by certain factors (e.g. climatic, topographical and biological needs of plants and animals) if these exceed the maximum or minimum tolerance limits of that organism. Shelford`s Law of Toleration curve (Helaouёt and Beaugrand 2009, with amendments). (The tolerance range is the interval between the minimum and maximum values of the environmental factor in which the species can survive. In the areas of reproduction, growth and feeding, reproduction, growth and feeding can occur. The critical range is the range where the death of individuals begins, i.e. the environmental factor varies from a minimum lethal value to a lethal value of 100% within this range) Tolerance ranges (i.e. ecological valences) to various environmental factors are formed during the evolutionary processes of adaptation of plants to the environment of a spectrum of species, i.e. as a result of natural selection (Mickelbart et al. 2015), including tree species (Körner et al. 2016). Therefore, the question arises as to whether the quantitative characteristics of hormesis (width and amplitude of the hormetic zone) and the range of stimulant doses differ between plant species with different tolerance ranges to the same environmental factor, i.e.
whether these quantitative characteristics of hormesis are species-specific. The most common graph used to illustrate the tolerance limits of a species is a bell-shaped curve represented as a function of the number of individuals in a population and the values of the relevant abiotic factor. Although related, these two laws do not propose exactly the same thing, as Shelford emphasizes the fact that the absence or presence of an organism in an ecosystem depends on the absence or excess of one of the many abiotic factors that are too close to tolerance limits. Lande R (2014) Evolution of phenotypic plasticity and environmental tolerance with unstable quantitative character in fluctuating environments. J Evol Biol 5:866-875. doi.org/10.1111/jeb.12360 Environmental limiting factors with values close to species tolerance limits are crucial for plant productivity, including woody species (Greenberg et al. 2015). In this regard, managing plant resistance to limiting factors through hormetic preconditioning offers an important perspective for increasing the productivity of woody plants in forestry. Shelford suggested what many today may spontaneously suspect: that the presence of an organism and its abundance in a given environment depend not only on the nutrients it receives for food, but also on other factors external to itself.
The tolerance interval of species to an environmental factor (or ecological valence) is the interval between the minimum and maximum values of the environmental factor within which the species can survive (Shelford 1913; Faith and Lyman, 2019). This range is defined by a set of tolerance ranges for all individuals of the species and is always greater than individual tolerance (Lynch and Gabriel 1987; Faith and Lyman, 2019). Environmental factors whose values are close to the limits of the tolerance range are environmentally limiting factors for species. Limiting factors play a crucial role in the geographical distribution of plant species, including woody plants; They determine the species` ranges, abundance and density, cover, growth rate and biomass. For example, they can influence the maximum response of forest stands (e.g., stand density and percentage of forest cover) under the environmental conditions of a given site (Greenberg et al. 2015). Walter J, Jentsch A, Beierkuhnlein C, Kreyling J (2013) Ecological stress memory and tolerance to cross-stress in plants in the face of climatic extremes. Environ Exp Bot 94:3-8. doi.org/10.1016/j.envexpbot.2012.02.009 Wani SH, Kumar V, Shriram V, Sah SK (2016) Phytohormones and their metabolic engineering fosr tolerance to abiotic stress in cultivated plants. Crop J 4(3):162-176. doi.org/10.1016/j.cj.2016.01.010 There are plants that can live in a certain moisture range but die if there is too much water or if the moisture index is below their lower tolerance limit. It was developed in 1911 by American zoologist Victor Ernest Shelford.
The absence of an organism may be limited by the qualitative or quantitative inadequacy of the various environmental factors, which may reach the tolerance limits for that organism. Environmental factors were climate change, topographic location and biological needs of plants and animals. This law is perhaps the most accurate indication of natural complexity. Each individual or population is subject to ecological changes, which shows the minimum and maximum capacity for all complex environmental factors. The range in which it is performed from minimum to maximum means the tolerance limit of an organism, if all known factors are indeed within the particular range of a particular organism, but still fail, it is important to consider additional factors of interaction with other organisms. It has been studied that an organism can have a wide tolerance for one factor and a slight arrangement for another. If an organization has a wide range of all factors, it indicates that certain organizations are the most prevalent and help increase diversity in the community. Foyer CH, Rasool B, Davey JW, Hancock RD (2016) Cross-tolerance to biotic and abiotic stress in plants: a focus on resistance to apluse infall. J exp bot adv 67(7):2025–2037. doi.org/10.1093/jxb/erw079 Another example could be that of an animal living in temperate climates: in these climates, the temperature varies from one season to another, but the metabolism of the animal can withstand the thermal maxima and the minimum defined in its tolerance range.
It is known as Shelford`s Law of Toleration because it was proposed by American zoologist and animal ecologist Victor Ernest Shelford in the early 1900s. Shelford`s law of tolerance (Shelford 1931) is illustrated by a bell-shaped curve representing the relationship between the intensity of the environmental factor(s) and its preference for species or populations. It is a fundamental basis of ecology when considering the laws of environmental influences on living systems (Odum and Barrett 2004) and applies to plant biology (Hatfield and Prueger 2015), agriculture (Zinn et al. 2010; Badr et al., 2020) and forestry (Greenberg et al., 2015; Tan et al., 2017) to control plant resistance to environmental limiting factors and increase plant productivity. Areas of intolerance are areas of value of environmental factors that make it impossible for a species to survive (Faith and Lyman 2019). It follows that due to preconditioning, hormesis can affect the width of the tolerance range in plants to some environmental factor or even other factors when acting after low-dose exposure. In addition, it has been suggested that the preconditioning effect can be maintained in a number of plant generations by epigenetic processes (Agathokleous and Calabrese 2020a).