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| {{Unreferenced|date=December 2009}}
| | The title of the writer is Numbers but it's not the most masucline name out there. Hiring is my occupation. California is our birth place. It's not a typical factor but what she likes doing is base leaping and now she is attempting to make cash with it.<br><br>My homepage ... [http://www.buzzbit.net/user/AFilson www.buzzbit.net] |
| '''Species evenness''' refers to how close in numbers each species in an environment are. Mathematically it is defined as a [[diversity index]], a measure of [[biodiversity]] which quantifies how equal the community is numerically. So if there are 40 foxes, and 1000 dogs, the community is not very even. But if there are 40 foxes and 42 dogs, the community is quite even. The evenness of a community can be represented by [[E. C. Pielou|Pielou]]'s evenness index:
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| :<math>J'={ H^\prime \over H_\max^\prime }</math>
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| Where <math>H^\prime</math> is the number derived from the [[Shannon index|Shannon diversity index]] and <math>H_\max^\prime</math> is the maximum value of <math>H^\prime</math>, equal to:
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| :<math>H^\prime_\max = - \sum_{i=1}^S {1\over S} \ln {1\over S} = \ln S.</math>
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| '''''J'''''' is constrained between 0 and 1. The less variation in communities between the species, the higher '''''J'''''' is.
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| Other indices have been proposed by authors where <math>H_\min^\prime > 0</math> e.g. Hurlburt's evenness index.
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| '''S''' is the total number of species.
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| == External links ==
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| * {{cite journal | first1 = C. P. H. | last1 = Mulder | first2 = E. | last2 = Bazeley-White | first3 = P. G. | last3 = Dimitrakopoulos | first4 = A. | last4 = Hector | first5 = M. | last5 = Scherer-Lorenzen | first6 = B. | last6 = Schmid | id = {{citeseerx|10.1.1.112.373}} | title = Species evenness and productivity in experimental plant communities | journal = Oikos | year = 2004 | volume = 107 | pages = 50–63 }}
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| {{DEFAULTSORT:Species Evenness}}
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| [[Category:Measurement of biodiversity]]
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| {{Ecology-stub}}
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Latest revision as of 03:55, 30 December 2014
The title of the writer is Numbers but it's not the most masucline name out there. Hiring is my occupation. California is our birth place. It's not a typical factor but what she likes doing is base leaping and now she is attempting to make cash with it.
My homepage ... www.buzzbit.net