Algae - Distribution


The topic of distribution of algal species has been fairly well studied since the founding of phytogeography in the mid-19th century AD. Algae spread mainly by the dispersal of spores analogously to the dispersal of Plantae by seeds and spores. Spores are everywhere in all parts of the Earth: the waters fresh and marine, the atmosphere, free-floating and in precipitation or mixed with dust, the humus and in other organisms, such as humans. Whether a spore is to grow into an organism depends on the combination of the species and the environmental conditions of where the spore lands.

The spores of fresh-water algae are dispersed mainly by running water and wind, as well as by living carriers. The bodies of water into which they are transported are chemically selective. Marine spores are spread by currents. Ocean water is temperature selective, resulting in phytogeographic zones, regions and provinces.

To some degree the distribution of algae is subject to floristic discontinuities caused by geographical features, such as Antarctica, long distances of ocean or general land masses. It is therefore possible to identify species occurring by locality, such as "Pacific Algae" or "North Sea Algae". When they occur out of their localities, it is usually possible to hypothesize a transport mechanism, such as the hulls of ships. For example, Ulva reticulata and Ulva fasciata travelled from the mainland to Hawaii in this manner.

Mapping is possible for select species only: "there are many valid examples of confined distribution patterns." For example, Clathromorphum is an arctic genus and is not mapped far south of there. On the other hand, scientists regard the overall data as insufficient due to the "difficulties of undertaking such studies."

Read more about this topic:  Algae

Other articles related to "distribution":

Hidden Markov Model - Types
... states emit the observations according to some probability distribution ... One such example of distribution is Gaussian distribution, in such a Hidden Markov Model the states output is represented by a Gaussian distribution ...
Convergence Of Random Variables - Convergence in Distribution - Properties
... Since F(a) = Pr(X ≤ a), the convergence in distribution means that the probability for Xn to be in a given range is approximately equal to the probability that the value of X is in that range, provided ... In general, convergence in distribution does not imply that the sequence of corresponding probability density functions will also converge ... These random variables converge in distribution to a uniform U(0, 1), whereas their densities do not converge at all ...
Markov Chains - Steady-state Analysis and Limiting Distributions - Steady-state Analysis and The Time-inhomogeneous Markov Chain
... A Markov chain need not necessarily be time-homogeneous to have an equilibrium distribution ... If there is a probability distribution over states such that for every state j and every time n then is an equilibrium distribution of the Markov chain ... matrix respects a shared equilibrium distribution ...

Famous quotes containing the word distribution:

    In this distribution of functions, the scholar is the delegated intellect. In the right state, he is, Man Thinking. In the degenerate state, when the victim of society, he tends to become a mere thinker, or, still worse, the parrot of other men’s thinking.
    Ralph Waldo Emerson (1803–1882)

    The man who pretends that the distribution of income in this country reflects the distribution of ability or character is an ignoramus. The man who says that it could by any possible political device be made to do so is an unpractical visionary. But the man who says that it ought to do so is something worse than an ignoramous and more disastrous than a visionary: he is, in the profoundest Scriptural sense of the word, a fool.
    George Bernard Shaw (1856–1950)

    My topic for Army reunions ... this summer: How to prepare for war in time of peace. Not by fortifications, by navies, or by standing armies. But by policies which will add to the happiness and the comfort of all our people and which will tend to the distribution of intelligence [and] wealth equally among all. Our strength is a contented and intelligent community.
    Rutherford Birchard Hayes (1822–1893)