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In ternationa l
Scholars
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African Journal of Environmental Economics and Management ISSN 2375-0707 Vol. 10 (3), pp. 001-002, 
March, 2022. Available online at www.internationalscholarsjournals.org © International Scholars Journals 

 

Author(s) retain the copyright of this article. 
 
 

 

SHORT COMMUNICATION 

 

Adaptive success index: A criterion for identifying 
most important species 

 
Diogo S. B. Rocha*, Leilton S. Damascena and Flávio França 

 
*Departamento de Ciências Biológicas, Laboratório de Taxonomia Vegetal, Universidade Estadual de Feira 

de Santana (UEFS), Bahia, Brasil. 
 

Accepted 11 October, 2021 
 

This article introduces the Adaptive Success Index (ASI) as a criterion for deciding which species are 
actually important in a given list of species either based on the Importance Value Index (IVI) or on the 
Cover Value Index (CVI). 

 
Key words: Adaptive Success Index (ASI), Importance Value Index (IVI), Cover Value Index (CVI). 

 
 
INTRODUCTION 

 
Phytosociology is the analysis of co-inhabitance, 
structure and constitution of groups of plants as well as 
the processes that favor continuity or change within a 
group of plants in time-space (Martins, 2004). Description 
of communities through phytosociology has evolved 
along with ecology towards a quantitative approach. 
Attributes such as dominance, frequency and covering 
are parameters used in order to describe communities in 
numbers (Moreira, 2007).  

Importance Value index (IVI) and Cover Value Index 
(CVI) only classify species according to their importance, 
failing to present useful criteria when it comes to 
assessing the importance of a group of species within a 
given community. In addressing this problem, this work 
aims at proposing criteria that can be used to classify 
species that present more significant adaptive success 
within a community.  

Assuming that IVI is the result of adding three relative 
parameters – Density, Dominance and Frequency, the 
result is inversely proportional to Pielou’s J’ equability, 
which assesses heterogeneity. IVI is inversely 
proportional to J’ because if the first is very high it means 
vegetation is more homogeneous (Müeller-Dombois and 
Ellemberg, 1974). Adaptive Success Index is based on 
the premise that species within the most successful  
 
 
 
*Corresponding author. E-mail: diogosbr@gmail.com. 

 
 
 
 

 
group are more adapted to the environment under study. 
 
 
Enunciation 

 

Adaptive Success Index (ASIivi) is reached through the 

ratio between the Importance Value Indexes (IVI) of each 
species and the triple of the equability (J’) in the sampled 
area. J’ is multiplied by three because the IVI is the result 
of the sum of the three relative values. 
 
ASIivi = IVIi/(3J’) 
 
Where: IVIi is the importance value index of the ‘ITH’ 
species. 

 
Species presenting an ASI value equal or above the 
average ASI were considered to be the most successful 
ones ecologically, which is the simple arithmetic average 
of the ASI for each species in the sampled area. 
 
Average ASI ivi = Σ ASI ivi/n 
 
Where n is the number of species. 
 
Considering that the IVI uses the frequency of the 
sampled species in its construction, this fact is directly 
influenced by the size of the sample (Moreira, 2007). We 
propose an alternative to use the Adaptive Success Index 
(ASI) based on the Cover Value Index (CVI). 



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In this case the Adaptive Success Index will be 
calculated through the ratio between the CVI and the 
double of the value of J’ since the CVI value is the sum of 
these two relative values. 
 

ASIc=IVCi/(2J’) 
 
Species presenting an ASIc above or equal to average 
ASIc were considered to be the most successful ones 
ecologically, which is the simple arithmetic average of the 
ASIc. 
 

Average ASI=ΣISAc/n 

 

Where n= number of species. 
 

 

CONCLUSION AND USES 

 

Adaptive success indexes, particularly the one based on 
the vegetation cover, can provide the analyses of 
vegetation indexes with a quantitative approach on the 
contribution of vegetation structure to reflectance values. 
This analysis might prove fundamental to the 
classification of vegetation and to the understanding of 
ecological dynamics.  

Since ASI classifies the most important species based 
on their importance indexes (IVI and CVI), significant 
contribution of a species to the construction of local 
vegetation physiognomy can be accessed. 

 
 
 
 

 

ASI can contribute to comparisons among different 
areas, hence helping classify vegetation through floristic 
composition. One can compare groups formed by species 
with more significant adaptive success among areas 
under study along with grouping analysis and infer on the 
similarity among certain areas. 
 

 
REFERENCES 
 
Martins FR (2004). O Papel da fitossociologia na conservação e na 

bioprospecção. Anais do 55º Congresso Nacional de Botância: 
Simpósios, Palestras e Mesas-Redondas. Sociedade Botânica do 
Brasil e Universidade Federal de Viçosa, Viçosa, Edição em CD-R.  

Moreira CM (2007). Avaliação de métodos fitossociológicos através de 
simulações de amostragens numa parcela permanente de cerradão, 
na Estação Ecológica de Assis, SP. Msc. Escola Superior de 
Agricultura Luiz de Queiroz, Piracicaba, SP.  

Müeller-Dombois D, Ellemberg H (1974). Aims and methods of 
vegetation analysis. New York: Wiley, p. 574.