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Leaf Area Ratio
Plant growth analysis refers to a set of concepts and equations by which changes in size of plants over time can be summarised and dissected in component variables. It is often applied in the analysis of growth of individual plants, but can also be used in a situation where crop growth is followed over time. Absolute size In comparing different treatments, genotypes or species, the simplest type of growth analysis is to evaluate size of plants after a certain period of growth, typically from the time of germination. In plant biology, size is often measured as dry mass of whole plants (M), or the above-ground part of it. In high-throughput phenotyping platforms, the amount of green pixels as derived from photographs taken from plants from various directions is often the variable that is used to estimate plant size. Absolute growth rate (AGR) In the case that plant size was determined at more than one occasion, the increase in size over a given time period can be determined. This is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Leaf Area
Specific leaf area (SLA) is the ratio of leaf area to leaf dry mass. The inverse of SLA is Leaf Mass per Area (LMA). Rationale Specific leaf area is a ratio indicating how much leaf area a plant builds with a given amount of leaf biomass: SLA \ = \ \frac where A is the area of a given leaf or all leaves of a plant, and ML is the dry mass of those leaves. Typical units are m2.kg−1 or mm2.mg−1. Leaf mass per area (LMA) is its inverse and can mathematically be decomposed in two component variables, leaf thickness (LTh) and leaf density (LD): LMA \ = \ \frac \ = LTh.LD Typical units are g.m−2 for LMA, µm for LTh and g.ml−1 for LD. Both SLA and LMA are frequently used in plant ecology and biology. SLA is one of the components in plant growth analysis, and mathematically scales positively and linearly with the relative growth rate of a plant. LMA mathematically scales positively with the investments plants make per unit leaf area (amount of protein and cell wall; cell numbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biomass Allocation
Biomass allocation is a concept in plant biology which indicates the relative proportion of plant biomass present in the different organs of a plant. It can also be used for whole plant communities. Rationale Different organs of plants serve different functions. Leaves generally intercept light and fix carbon, roots take up water and nutrients, and stems and petioles display the leaves in a favourable position and transport various compounds within the plant. Depending on environmental conditions, plants may change their investment scheme, to make plants with relatively bigger root systems, or more leaves. This balance has been suggested to be a ‘functional equilibrium’, with plants that experience low water or nutrient supply investing more in roots, and plants growing under low light or CO2 conditions investing more in leaves or stems. Alternatively, it is also known as the 'balanced growth hypothesis', or the 'optimal partitioning theory'. Next to environmentally-induced cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allometry
Allometry is the study of the relationship of body size to shape, anatomy, physiology and finally behaviour, first outlined by Otto Snell in 1892, by D'Arcy Thompson in 1917 in ''On Growth and Form'' and by Julian Huxley in 1932. Overview Allometry is a well-known study, particularly in statistical shape analysis for its theoretical developments, as well as in biology for practical applications to the differential growth rates of the parts of a living organism's body. One application is in the study of various insect species (e.g., Hercules beetles), where a small change in overall body size can lead to an enormous and disproportionate increase in the dimensions of appendages such as legs, antennae, or horns The relationship between the two measured quantities is often expressed as a power law equation (Allometric equation) which expresses a remarkable scale symmetry: : y = kx^a \,\! or in a logarithmic form: : \log y = a \log x + \log k\,\! or similarly \ln y = a \ln x ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isometry
In mathematics, an isometry (or congruence, or congruent transformation) is a distance-preserving transformation between metric spaces, usually assumed to be bijective. The word isometry is derived from the Ancient Greek: ἴσος ''isos'' meaning "equal", and μέτρον ''metron'' meaning "measure". Introduction Given a metric space (loosely, a set and a scheme for assigning distances between elements of the set), an isometry is a transformation which maps elements to the same or another metric space such that the distance between the image elements in the new metric space is equal to the distance between the elements in the original metric space. In a two-dimensional or three-dimensional Euclidean space, two geometric figures are congruent if they are related by an isometry; the isometry that relates them is either a rigid motion (translation or rotation), or a composition of a rigid motion and a reflection. Isometries are often used in constructions where one space i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allometric
Allometry is the study of the relationship of body size to shape, anatomy, physiology and finally behaviour, first outlined by Otto Snell in 1892, by D'Arcy Thompson in 1917 in ''On Growth and Form'' and by Julian Huxley in 1932. Overview Allometry is a well-known study, particularly in statistical shape analysis for its theoretical developments, as well as in biology for practical applications to the differential growth rates of the parts of a living organism's body. One application is in the study of various insect species (e.g., Hercules beetles), where a small change in overall body size can lead to an enormous and disproportionate increase in the dimensions of appendages such as legs, antennae, or horns The relationship between the two measured quantities is often expressed as a power law equation (Allometric equation) which expresses a remarkable scale symmetry: : y = kx^a \,\! or in a logarithmic form: : \log y = a \log x + \log k\,\! or similarly \ln y = a \ln x ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolic Scaling Theory
Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the conversion of food to building blocks for proteins, lipids, nucleic acids, and some carbohydrates; and the elimination of metabolic wastes. These enzyme-catalyzed reactions allow organisms to grow and reproduce, maintain their structures, and respond to their environments. The word metabolism can also refer to the sum of all chemical reactions that occur in living organisms, including digestion and the transportation of substances into and between different cells, in which case the above described set of reactions within the cells is called intermediary (or intermediate) metabolism. Metabolic reactions may be categorized as ''catabolic'' – the ''breaking down'' of compounds (for example, of glucose to pyruvate by cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolic Theory Of Ecology
The metabolic theory of ecology (MTE) is the ecological component of the more general Metabolic Scaling Theory and Kleiber's law. It posits that the metabolic rate of organisms is the fundamental biological rate that governs most observed patterns in ecology. MTE is part of a larger set of theory known as metabolic scaling theory that attempts to provide a unified theory for the importance of metabolism in driving pattern and process in biology from the level of cells all the way to the biosphere. MTE is based on an interpretation of the relationships between body size, body temperature, and metabolic rate across all organisms. Small-bodied organisms tend to have higher mass-specific metabolic rates than larger-bodied organisms. Furthermore, organisms that operate at warm temperatures through endothermy or by living in warm environments tend towards higher metabolic rates than organisms that operate at colder temperatures. This pattern is consistent from the unicellular level up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relative Growth Rate
Relative growth rate (RGR) is growth rate relative to size - that is, a rate of growth per unit time, as a proportion of its size at that moment in time. It is also called the exponential growth rate, or the continuous growth rate. Rationale RGR is a concept relevant in cases where the increase in a state variable over time is proportional to the value of that state variable at the beginning of a time period. In terms of differential equations, if S is the current size, and \frac its growth rate, then relative growth rate is :\frac\frac. If the relative growth rate is constant, i.e., :\frac\frac = k, a solution to this equation is :S_t = \exp^. A closely related concept is doubling time. Calculations In the simplest case of observations at two time points, RGR is calculated using the following equation: :RGR \ = \ \frac, where: \ln = natural logarithm t_1 = time one (e.g. in days) t_2 = time two (e.g. in days) S_1 = size at time one S_2 = size at time two When calculating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
