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词条 Indicator value
释义

  1. Ellenberg's Indicator Value

  2. Indicator Value of Dufrêne and Legendre

  3. References

Indicator value is a term that has been used in ecology for two different indices. The older usage of the term refers to Ellenberg's indicator values, which are based on a simple ordinal classification of plants according to the position of their realized ecological niche along an environmental gradient.[1] More recently, the term has also been used to refer to Dufrêne & Legendre's indicator value, which is a quantitative index that measures the statistical alliance of a species to any one of the classes in a classification of sites.[2]

Ellenberg's Indicator Value

Ellenberg's indicator values[1] were the first model of bioindication proposed and applied to the flora of Germany, and they have a long tradition in interpretation and understanding of plant communities and their evolution. The latest edition of Ellenberg's indicator values applies a 9-point scale for each of six gradients: soil acidity, soil productivity or fertility, soil humidity, soil salinity, climatic continentality and light availability.[3] Indicator values have also been published for Switzerland,[4] Great Britain,[5] and some other floras. A substantial advance on a comparable scale to place a local flora on gradients are the climatic profiles of the French SOPHY online database.{{Citation needed|date=December 2012}}

Indicator Value of Dufrêne and Legendre

This indicator value is an integral part of the indicator value , which quantifies the fidelity and specificity of species in relation to groups of sites in a user-specified classification of sites, and tests for the statistical significance of the associations by permutation.[2][6][7]

The indicator value of species i for class j is obtained with the equation

IndValij = 100 · Aij · Bij

Here

Aij is specificity, i.e. the proportion of the individuals of species i that are in class j

Bij is fidelity, i.e. the proportion of sites in class j that contain species i

References

1. ^1 Ellenberg H. Zeigerwerte der Gefässpflanzen Mitteleuropas / H. Ellenberg // Scripta geobotanica. Göttingen, 1974. – Vol. 9. – 197 p.
2. ^1 Dufrene, M., and P. Legendre. 1997. Species assemblages and indicator species: The need for a flexible asymmetrical approach. Ecological Monographs 67:345-366.
3. ^Ellenberg H., Weber H.E., Dull R., Wirth V., Werner W., Paulisen D. Zeigerwerte von Pflanzen in Mitteleuropa [Indicator values of plants in Central Europe] / H. Ellenberg, H.E. Weber, R. Dull, V. Wirth, W. Werner, D. Paulisen // Scripta Geobotanics. – V. 18. – Verlag Erich Goltze KG, Göttingen, 1991. – 248 s.
4. ^Landolt E. Okologische Zeigerwerts zur Schweizer Flora / E. Landolt // Veroff. Geobot. Inst. ETH. Zurich. – 1977. – H. 64. – S. 1-208.
5. ^{{cite book|last1=Hill|first1=M.O.|last2=Mountford|first2=J.O.|last3=Roy|first3=D.B.|last4=Bunce|first4=R.G.H.|title=Ellenberg's indicator values for British plants. ECOFACT Volume 2. Technical Annex|date=1999|publisher=Institute of Terrestrial Ecology|isbn=1870393481|url=http://nora.nerc.ac.uk/6411/1/ECOFACT2a.pdf|accessdate=29 May 2017}}
6. ^De Caceres, M., and P. Legendre. 2009. Associations between species and groups of sites: indices and statistical inference. Ecology 90:3566-3574.
7. ^De Caceres, M., P. Legendre, and M. Moretti. 2010. Improving indicator species analysis by combining groups of sites. Oikos 119:1674-1684.
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