Species diversity and successional dynamics in the secondary forest of Obafemi Awolowo University Biological Gardens Ile-Ife, Nigeria

Abstract

Forests worldwide are being continuously disturbed by human activities and natural events, and tropical rainforest disturbance is specifically pronounced as indicated by its low biodiversity status. This study examined the floristic composition, species diversity and evenness in seven sample plots (100, 200, 400 and 2500 m2) in a secondary forest of different ages in the Biological Gardens of the Obafemi Awolowo University, Ile-Ife. The aim of this study was to determine changes in these parameters with succession. In each sample plot, all vascular plant species were accounted for and enumerated. The data collected were used to establish the floristic composition, density, diversity and evenness of plant species in the forest. There were 85 woody species (69%), 3 grass species (2%), 13 forb species (11%) and 21 climber species (17%) in the forest. These concern 113 genera and 52 families. The number of woody species in the plots varied with the age of the plots, however, there were no clear trends in the density and diversity of species with plot age. The forest was dominated by early successional species (50%) against the 33% contributed by the late successional species. Also, the youngest plot (Plot I) was dominated by early successional species while the older plots were dominated by a mixture of both early and late successional species. The similarity between plots during succession in the tropical forest was higher between plots of the same age. Also, this study showed that because of the directional pattern of succession, the species that converge to make up the diversity of forest of ages under consideration may be predictive of its recovery.

Full text

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Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002
SPECIES DIVERSITY AND SUCCESSIONAL DYNAMICS
IN THE SECONDARY FOREST OF OBAFEMI AWOLOWO UNIVERSITY
BIOLOGICAL GARDENS ILE-IFE, NIGERIA
Nelson O. Uwalaka*, Joseph I. Muoghalu, Afolabi O. Osewole
Obafemi Awolowo University, Nigeria
*e-mail: uwalakanelson@gmail.com
Received: 01.08.2017
Forests worldwide are being continuously disturbed by human activities and natural events, and tropical rainfor-
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that converge to make up the diversity of forest of ages under consideration may be predictive of its recovery.
Key words: diversity, evenness, plant succession, secondary forest, similarity, successional species
Introduction
-
        -
sodic disturbance slowly regenerates a semblance of
its former self in the absence of further disturbances
-
tional process of community change in which commu-
nities replace each other sequentially until a stable com-
  
are being continuously disturbed by human activities
and natural events, and tropical rainforest disturbance
-
diversity status of tropical forests worldwide and the

disturbance drastically alters the community in the
disturbed area, and causes it to transform to an earlier
     

community. Forest disturbance is now pronounced in
    
-
rectional change in community composition following
-
don, 2008). Some studies have demonstrated that in
tropical forest fragments, the disturbances, whether

critical in determining the dynamics of tree commu-
  


   
visualised as a continuum from an early stage where
the factors that govern colonisation are most impor-

    
stored seeds and re-sprouts), to later stages where com-
petitive ability and environmental requirements of spe-

  
shade tolerance) largely dictate patterns of species re-


      -
bance is believed to be one of the main factors in-
 
      
in communities where post-disturbance succession
is not driven by competitive regimes, disturbance
       


22
chronosequence studies have also documented
rapid recovery of species richness and species di-
versity during tropical forest succession, but these

      


       
during tropical wet forest succession, three factors
are probably involved. First, long-living pioneer
species persist well into the understorey re-initia-
tion stage, pre-empting space and slowing the rate
of species turnover. Second, low light availability
in young and intermediate aged old-growth forests
and the rarity or absence of canopy gaps may re-
strict establishment and recruitment of gap-requir-

low seed availability may limit colonisation of tree

-
cession in a relatively small area where factors such
as soil fertility and land use history are similar, thus
facilitating a more in depth assessment of the suc-
cessional pattern without these confounding factors.

      
      
clearing, farming, establishment of infrastructural
facilities or fuelwood gathering. Knowledge on the
recovery pattern of tropical forests from previous
perturbations is important in the conservation of its
-
der to halt the current increasing rate of forest dis-
      
       

similar ages show the same pattern of species simi-
      

questions, the successional processes in disturbed
   -

and comparisons made in terms of species composi-

the species richness and diversity of these disturbed
  

Material and Methods
Study area
       

abundant plant species are Albizia zygia
 Blighia unijugata  Bombax buon-
opozense Bosqueia angolensis Ficalho,
Commiphora kerstingii Engl., Elaeis guineensis
 Ficus mucuso Funtumia
elastica   Holarrhena oribunda
   Manihot glaziovii
   Pycnanthus angolensis 
       
-
    
  
       -


-
      -



      
-2

 
soils, which are usually acidic, contain less than



2 sec-

-
         
-
       


-
eral natural regeneration monitoring studies have
  

2) marked out before the incidence
         

-
tural characteristics. Seven plots, between latitudes
  
 -
  




ages of the plots was estimated since the last time of
stand disturbance.
Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002


Fig.       
study was carried out.
       -
cept for the presence of some mature tree spe-
cies and some regrowths that have colonised
    -
ing woody species, herbs, climbers, and some
mosses growing on decaying felled wood were
present in the plots.
Data collection
  
       
       
      




has undergone a series of successional stages,
in terms of species composition, diversity and
     
used as a plot with which the selected plots
    -
cies were determined. Specimens of plant spe-

      
  -
ing vegetation attributes were determined for
     -1),
   
   
of similarity between the plots.
Data analysis
   -
tablished by listing all the species encountered in
each plot and summing up to get the total number

of species per plot was used to compile a list of
dominant woody species and their successional
status was determined according to the results of
      
abundance were termed dominant.
Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002


Table 1. 
    
7°  °  
 7° ° 288 
 7° °  
 7° °  
7° °  
 7° °  
 7° °  
 7° °  >70 years

succession, the similarity in species composition in
each plot were compared using the Sørensen in-
       
the measurement of the similarity and dissimilar-
ity between sampling plot pairs was based on the
presence or absence of species of interest in each


   
indicate nearly identical community composition
between the pair of plots and values near 0 indi-
cates that communities have very little composi-


BA
C
ISS +
=2

   


   
∑
−= )
1
ii PPH
       
N
ni
P
i=  
i is the
number of individuals of species.
      
      
)
1
S
H
J=       

 -
tion of the density, diversity and evenness indices

Results
Floristic composition and successional status
of woody species in the plots
        -
 
-

 
      
        



-

         
   -

  
 
the plots having the highest number of woody species

      -
   
     
species were Cola millenii K. Schum., Ficus mucoso
 Mallotus oppositifolius
and Newbouldia laevis 

varied with the age of the plots.
   -
-
          

there was an abundant number of Bambusa vulgaris
 which suppressed the growth of
many woody species and as such, the woody species
found were thin-stemmed and short.

     
      
      

      

species could not be determined.
Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002


Table 2. -

)
   
















1Abutilon sp.   +
Acanthus montanus
     + +   
Albizia adianthifolia
Schum. Fabaceae +
Albizia lebbeck 
 Fabaceae +
Albizia zygia 
 Fabaceae + + + + ++
7
Alchornea cordifolia


Euphorbiaceae +
8
Alchornea laxiora


Euphorbiaceae + + +
Allophylus africanus
 Sapindaceae   ++
10 Alstonia boonei 
       ++
11 Antiaris africana Engl.    ++++ +
12 Anthocleista djalonensis
    +
 Antidesma sp. Euphorbiaceae +   
 Baphia nitida  Fabaceae ++
 Blighia sapida 
Koenig. Sapindaceae + + +++
 Blighia unijugata  Sapindaceae + +
17 Bombax buonopozense
         +
18 Bridelia ferruginea
 Euphorbiaceae   ++  
 Bridelia micrantha
 Euphorbiaceae +
20 Capsicum frutescens  Solanaceae +   +   
21 Carpolobia lutea 
    + +   + +
22 Cassia sp. Fabaceae   +
 Celtis mildbraedii Engl.   + + +  
 Celtis philippensis
         +
 Celtis zenkeri Engl.     ++++
 Chassalia kolly
 Rubiaceae + +
27 Chrysophyllum albidum
 Sapotaceae ++
28 Cnestis ferruginea     ++++ 
 Coea ebracteolata
 Rubiaceae +
 Cola millenii K. Schum. Sterculiaceae   ++++++
 Dalbergia lactea  Fabaceae ++ 
 Daniella ogea 
 Fabaceae +
Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002


)
   
















Deinbollia pinna-
ta 

Sapindaceae ++ +   +
 Dialium guineense
 Fabaceae +
 Diospyros monbuttensis
 Ebenaceae +  +  +
 Dracaena arborea
         +
 Drypetes sp. Euphorbiaceae +  
 Elaeis guineensis     + 
 Fagara leprieurii
 Rutaceae +   
 Ficus exasperata   +
 Ficus mucoso   +++++  +
 Funtumia elastica
    +++++
 Glyphaea brevis
    ++ +
 Hedranthera barteri
    + + + 

Holarrhena oribunda


  + + +  +
 Homalium letestui
 Samydaceae + 
 Icacina trichantha    ++ +   
 Lecaniodiscus
cupanioides  Sapindaceae + +   +
 Microdesmis puberula
    +++  +
 Mallotus oppositifolius
 Euphorbiaceae ++++++
 Manihot glaziovii 
 Euphorbiaceae ++
 Margaritaria discoidea
 Euphorbiaceae + 

Milletia thonningii


Fabaceae +  +
 Monodora tenuifolia
    ++
 Morinda lucida  Rubiaceae +
 Myrianthus arboreus 
      +  +
 Napoleona imperialis 
    ++++ 
 Napoleona vogelii
       ++

Newbouldia laevis


 ++++ + + +
 Olax sp.      + +  
 Oxyanthus speciosus
 Rubiaceae +
Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002

27
)
   















 Pauridiantha hirtella
 Rubiaceae + 
 Pavetta corymbosa
 Rubiaceae   ++  

Phyllanthus
muellerianus 

Euphorbiaceae + +

Piliostigma thonningii

Redh.
Fabaceae +  
 Piptadenastrum africa-
num  Fabaceae +  +
 Psychotria sp. Rubiaceae   +
 Pterocarpus
mildbraedii  Fabaceae ++
 Pycnanthus angolensis
  +  ++
70 Rauvola vomitoria
         +
71
Ricinodendron
heudelotii 

Euphorbiaceae   +++++ 
72 Ritchiea sp.     +   
 Rothmannia longiora
Salisb. Rubiaceae +  
 Securinega virosa
 Euphorbiaceae + +
 Solanum erianthum 
 Solanaceae + 
 Sorindeia warneckei
Engl.   ++ 
77 Sphenocentrum
jollyanum  Sterculiaceae   +++++
78 Spondias mombin    ++
 Sterculia tragacantha
 Sterculiaceae + +
80
Tetrapleura tetraptera


Fabaceae +
81 Trema orientalis 
  ++
82 Trichilia heudelotii
         +
 Trichilia prieureana 
   ++ +   +
 Trilepsium
madagascariense      + + + +
 Voacanga africana
Stapf.  + + +

1Anchomanes diormis
     +   
2Asystasia gangetica 
   ++  +
Canna indica   +
Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002

28
)
   















Carica papaya   + + 

Chromolaena odorata

Rob.
 +  +   
Commelina sp.      +  
7Cyathula sp.   ++   
8Maranthocleoa sp.     +   
Musa sapientum      +   
10 Petiveria alliacea    + + 
11 Phaulopsis barteri 
  +
12 Talinum triangulare
       + 

1Bambusa vulgaris
    +
2Digitaria exilis
  ++ 
Panicum maximum
  + + + 

1Abrus precatorius  Fabaceae +
2Acacia ataxacantha
 Fabaceae +  +
Alaa barteri      ++
Baissea sp.   ++ + + +
Cissus sp.  + + + +   
Combretum sp.  +++++++
7Culcasia scandens 
      +  
8Hippocratea sp.    ++
Jateorhiza sp.  ++ +
10 Leptoderris micrantha
 Fabaceae +  
11 Memecylon sp.     +   
12 Mezoneuron
benthamianum  Fabaceae + +
 Momordica charantia
  +++
 Mondia whitei 
f.) Skeels   +
 Mussaenda eleganz
 Rubiaceae + 
 Parquetina nigrescens
  +
17 Paullinia pinnata  Sapindaceae + + 
18 Phyllantus sp. Euphorbiaceae +
 Salacia erecta 
        +
20 Sida urens   +
21 Smilax kraussiana
 Smilacaceae   +  + 
22 Thunbergia sp.     +   

Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002


Table 3.
 















  20 27 28    
 2 1 1 0 0 2 0 0
   11 1 1 0
  7     
 27      21 
       21 
  22    18  
-1)       

      2.82  
        
Table 4.-

Species name Successional status 
       
Albizia lebbeck Early       +
Albizia zygia Early + +     
Alchornea cordifolia Early +     
Alchornea laxiora Early      ++
Alstonia boonei Early      + 
Blighia sapida Early ++++
Carpolobia lutea     +   +
Celtis zenkeri Early    +  +
Cnestis ferruginea     +   
Cola millenii Early    +++  
Deinbollia pinnata   ++   +
Ficus exasperata Early +       
Ficus mucoso Early + +      
Funtumia elastica Early    +++
Glyphaea brevis        +
Icacina trichantha   ++   
Lecaniodiscus cupanioides     +   +
Mallotus oppositifolius   +     
Microdesmis puberula     +   +
Napoleona imperialis     +   
Napoleona vogelii         +
Newbouldia laevis Early + +     +
Olax sp.       + 
Petivera alliacea   +     
Phyllanthus muellerianus    +    
Solanum erianthum  +      
Spondias mombin   +     
Trema orientalis Early +       
Trichilia prieureana Early        +
Trilepsium madagascariensis Early        +
Structural characteristics: density, diversity
and evenness of the plots
       
-

       
       

species were dominant in terms of their densities

Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002


Table 5.-

Species name Family 
       
Albizia lebbeck Fabaceae        
Albizia zygia Fabaceae 10      
Alchornea cordifolia Euphorbiaceae 17      
Alchornea laxiora Euphorbiaceae      8 
Alstonia boonei         
Blighia sapida Sapindaceae        
Carpolobia lutea         
Celtis zenkeri        10 
Cnestis ferruginea         
Cola millenii Sterculiaceae    710  
Deinbollia pinnata Sapindaceae        
Ficus exasperata  8      
Ficus mucoso  17       
Funtumia elastica         
Glyphae brevis        10 
Icacina tricantha     7   
Lecaniodiscus cupanioides Sapindaceae        
Mallotus oppositifolius Euphorbiaceae        
Microdesmis puberula         8
Napoleona imperialis     7   
Napoleona vogelii         
Newbouldia laevis    10     
Olax sp.         
Petivera alliacea   8     
Phyllantus muellerianus Euphorbiaceae   8    
Solanum erianthum Solanaceae        
Spondias mombin         
Trema orientalis         
Trichilia prieureana         
Trilepsium madagascariensis         
  77      81
-
  -
tion to the ages of the plots did not follow a clear trend
        




were least evenly distributed in the youngest plot

Similarity of the plots
      

high similarity among them in their species composi-

-



the least similarity in terms of species composition


Discussion
-
position did not increase with age although the oldest
       

     
years since abandonment) are certainly more dynamic


density does not show a predictable pattern with stand
 Trema orientalis

         

Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002


Table 6. 
        
        0.21
      0.28  
 0.77 0.70      
        
0.87       
 0.77 0.72      
 0.88 0.81 0.71   0.70  
  0.70    0.+  


stages of secondary succession, species such as Trema
micrantha -

of some species in the older plots, such as Deinbollia
pinnata Icacina trichantha
 Lecaniodiscus cupanioides  Micro-
desmis puberula       
suggests that these species make up part of the late
successional stage of a forest. Furthermore, the older
-


the forest would be replaced with tree species that are

    
early successional phase of regeneration had a high
  
are still undergoing an early building phase of re-
  

of forest succession after site abandonment in lowland
moist and wet neotropics is characterised by vegeta-

       

did not have the highest number of species could be
attributed to succession, during which early colonis-
ers are lost leading to a subsequent drop in the species


  -
      
peak at intermediate phases of succession, followed by
  
        -
green forest fallow, where tree density increased over
7 years but stabilised after 10 years.
Species diversity and evenness of species did
not follow a clear trend with age of plots in this
        
some early successional species in some of the plots.
 Trema orientalis dominated the spe-


that as the forest develops, new species begin to col-
onise and recruit, leading to a gradual accumulation

Some studies have documented an increasing
        
      




       -
sity is low because only the best competitors persist.

intensities and frequencies of disturbance, as well as
intermediate time since the last disturbance. Fantini
-
pecially species richness over time since abandon-
ment. Similar cases have been found in other studies

       


     

between relative abundance of species and stand
      
      
during succession as proposed in the model of suc-


of more early successional tree and grass species in

study showed that older plots had the highest diver-
sity which is in line with the assertion of Fantini et
      
greatest during mid-successional stages that contain
both early and late successional species.
Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002



study was the least in the youngest plot but high in

plot was still in the preliminary phase of coloni-
sation whereby newer species are still arriving,
whereas the older plots have attained some level of
stability and tending towards another successional

-


  
as a proportion of all species with successional age
and also because the proportion of rare tree species
was higher in the oldest site than in the youngest.
  
ages had more evenness pattern compared to those

       -
     
youngest plot had the least similarity with the un-
burnt plot as against the comparison made between

the young plot must pass through some seral stages

Conclusions and Recommendations
        
similar ages had higher similarities in species
  
        
seral stage, similarity increases provided they are
        
youngest plot had the least species diversity and
     
composition and evenness of distribution were not

conducted on a small area) can serve as a means
of predicting how a forest that has been disturbed
would look like, per seral stage, in terms of species
composition and diversity, most especially in the

-


of this study highlight the need for the establish-
  

with minimal human disturbance and has a high
value for biodiversity management and conser-
     
studies which will check the recovery of the for-
est can be conducted.
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
pattern of tree community dynamics in a secondary for-

Global Ecology and Conservation   

       
      
     Forest Ecology
and Management    



-
 Jour-
nal of Ecology 
      
Tropical Agriculture (Trini-
dad)
       
  -
munities in wet tropical secondary forests. Journal
of Ecology    

Map of Ecological zones of Nigerian Veg-
etation
       
human impact and natural disturbances. Perspectives
in Plant Ecology, Evolution and Systematics 

-
 
Tropical Forest Community Ecology

-
fects of climate and stand age on annual tree dynam-
ics in tropical second-growth rain forests. Ecology

       
        
change in tree communities of secondary tropical
Proceedings of
the Royal Society of London, Series B

   -
ating conditions in the dynamics of ecological com-
munities. American Naturalist   


reefs. Science    -


 
Journal of Ecology

Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002

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       
cover on seedling and sapling dynamics in sec-
       Jour-
nal of Tropical Ecology    

        
   Journal of Ecology 

       
  
      -
  ISRN Ecology   

  Legend to Soil Map of the World.
Vol.1. World soil classication
     Nature  

        -
       
Trends in Ecology and Evolution   

    -
   
Forest Succession:
Concepts and Application  -

  -
est succession: changes in structural and functional char-
acteristics. Forest Ecology and Management 

          -
   
Forest Succession: Concepts and Appli-
cation. 
         

  Journal of Tropical Ecology  

   An Outline of Nigerian Vegetation. 3rd
edition-

        -
cruitment, and canopy gap formation during a 10-year
period in a tropical moist forest. Ecology  



Ecology 
  

-
       -
sequence of tropical abandoned pastures: implications
for restoration ecology. Restoration Ecology

        -
Bio-
diversity in Managed Landscapes: Theory and Prac-
tice. 
      
and composition in altitudinal gradient on an in-
    Nigerian Journal of
Botany
-

Rodriguesia
     Forest Stand Dynamics.


term chronosequence of forest succession in the up-
  Journal of
Ecology 
  -
cal forests. Trends in Ecology and Evolution 

  
-
Revista Brasileira de Biologia

    
following slash and burn agriculture in north-eastern
Journal of
Ecology 
Soil Taxonomy, Agriculture Handbook. -

        -
       
forest after logging and shifting cultivation. Bio-
diversity and Conservation   

-
es controlling successional change. Oikos 
The Vegetation of Africa. A descriptive memoir
to accompany map of Africa.
Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002

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ВИДОВОЕ РАЗНООБРАЗИЕ И ДИНАМИКА СУКЦЕССИИ
ВТОРИЧНОГО ЛЕСА БИОЛОГИЧЕСКИХ САДОВ
УНИВЕРСИТЕТА ОБАФЕМИ АВОЛАУ, ИЛЕ-ИФЕ, НИГЕРИЯ
Н. О. Увалака*, Дж. И. Муогалу, А. О. Осеволе
Университет Обафеми Аволау, Нигерия
*e-mail: uwalakanelson@gmail.com
-


           2   
-
     
   
   

-
      
     
  

-
  



Ключевые слова:-

Nature Conservation Research. Заповедная наука 2018. 3(1): 21–34 DOI: 10.24189/ncr.2018.002