Various disciplines understand
heterogeneity, or being
heterogeneous, in different ways.
Biology Environmental heterogeneity Environmental heterogeneity is a
hypernym for different environmental factors that contribute to the diversity of species, like climate, topography, and land cover.
Biodiversity is correlated with
geodiversity on a global scale. Heterogeneity in geodiversity features and environmental variables are indicators of environmental heterogeneity. They drive biodiversity at local and regional scales. Scientific literature in ecology contains a big number of different terms for environmental heterogeneity, often undefined or conflicting in their meaning. and are a synonyms of environmental heterogeneity. A heterogeneous mixture is a
mixture of two or more
compounds. Examples are: mixtures of sand and water or sand and iron filings, a conglomerate rock, water and oil, a salad,
trail mix, and concrete (not cement). A mixture can be determined to be homogeneous when everything is settled and equal, and the liquid, gas, the object is one color or the same form. Various models have been proposed to model the concentrations in different phases. The phenomena to be considered are mass rates and reaction.
Homogeneous and heterogeneous reactions Homogeneous reactions are
chemical reactions in which the reactants and products are in the same
phase, while heterogeneous reactions have
reactants in two or more phases. Reactions that take place on the surface of a catalyst of a different phase are also heterogeneous. A reaction between two gases or two miscible liquids is homogeneous. A reaction between a gas and a liquid, a gas and a solid or a liquid and a solid is heterogeneous.
Geology Earth is a heterogeneous substance in many aspects; for instance,
rocks (geology) are inherently heterogeneous, usually occurring at the micro-scale and mini-scale.
Information technology With
information technology,
heterogeneous computing occurs in a
network comprising different types of computers, potentially with vastly differing
memory sizes, processing power and even basic underlying architecture.
Mathematics and statistics In algebra,
homogeneous polynomials have the same number of factors of a given kind. In the study of
binary relations, a
homogeneous relation R is on a single set (
R ⊆
X ×
X) while a
heterogeneous relation concerns possibly distinct sets (
R ⊆
X ×
Y,
X =
Y or
X ≠
Y). In statistical
meta-analysis,
study heterogeneity is when multiple studies on an effect are measuring somewhat different effects due to differences in subject population, intervention, choice of analysis, experimental design, etc.; this can cause problems in attempts to summarize the meaning of the studies.
Medicine In
medicine and
genetics, a
genetic or
allelic heterogeneous condition is one where the same disease or condition can be caused, or contributed to, by several factors, or in genetic terms, by varying or different
genes or
alleles. In
cancer research, cancer cell heterogeneity is thought to be one of the underlying reasons that make treatment of
cancer difficult.
Physics In
physics, "heterogeneous" is understood to mean "having physical properties that vary within the medium".
Sociology In
sociology, "heterogeneous" may refer to a society or group that includes individuals of differing ethnicities, cultural backgrounds, sexes, or ages. Diverse is the more common synonym in the context.
Ecology In
landscape ecology, heterogeneity refers to the different elements of a system. Heterogeneous systems support higher biodiversity and is a target for many landscape restoration efforts. == See also ==