Journal of Agriculture and Ecology Research
International
10(4): 1-15, 2017; Article no.JAERI.30953
ISSN: 2394-1073
SCIENCEDOMAIN international
www.sciencedomain.org
Effect of Environmental Factors on the Frequency
and Density of Three Functional Groups of
Woody Species in Ghana
Belayneh Bayu1,2*, William Hawthorne3, Frans Bongers1 and Lourens Poorter1
1
Forest Ecology and Forest Management Group, Wageningen University, P.O.Box 47, 6700 AA
Wageningen, The Netherlands.
2
Ethiopian Environment and Forest Research Institute, Bahir Dar Environment and Forest Research
Center, P.O.Box 2128, Bahir Dar, Ethiopia.
3
Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB,
United Kingdom.
Authors’ contributions
This work was carried out in collaboration between all authors. Author BB performed the statistical
analysis and wrote the manuscript. Author WH designed the study and performed data collection.
Authors LP and FB supervised the analysis of the study and the paper work. All authors read and
approved the final manuscript.
Article Information
DOI: 10.9734/JAERI/2017/30953
Editor(s):
(1) Maria Panitsa, Department of Environmental and Natural Resource Management, University of Patras, Greece.
Reviewers:
(1) F. O. Ogbemudia, University of Uyo, Ibom State, Nigeria.
(2) Muboko Never, Chinhoyi University of Technology, Zimbabwe.
(3) Sepalika C. Jayamanne, Uva Wellassa University, Passara Road, Badulla, Sri Lanka.
Complete Peer review History: http://www.sciencedomain.org/review-history/17924
Original Research Article
Received 11th December 2016
th
Accepted 13 February 2017
nd
Published 22 February 2017
ABSTRACT
How plant species are distributed in a given ecosystem is important for ecologists and
conservationists because tropical forests are very diverse. This makes the question of what
determines species commonness and rarity more interesting. This paper aims to assess the
environmental range, frequency and density of three plant functional groups (Pioneer, non-pioneer
light demanding and shade tolerant) in Ghanaian tropical forests. We established a 1-ha plot in
which trees were inventoried in a nested design, providing a total number of 2205 plots. All living
_____________________________________________________________________________________________________
*Corresponding author: E-mail: belaynehazene@yahoo.com;
Bayu et al.; JAERI, 10(4): 1-15, 2017; Article no.JAERI.30953
trees ≥ 30 cm diameter at breast height (DBH) were sampled in 1ha plot, trees 10–30 cm DBH in
0.1-ha subplots and trees 5–10 cm DBH in 0.05-ha subplots. Then, the following variables were
recorded and calculated; frequency (the number of plots in which the species is present) and the
average density (the average number of trees per plot, for the plot in which the species is present),
and environmental range (rain fall range and soil fertility) of each species. We used a KruskalWallis, Chi-square and multiple regression analysis to evaluate each research question. The
results showed that non-pioneer light demanding tree species have wider environmental range and
higher frequency than pioneer and shade tolerant tree species. This might be due to non-pioneer
light demanding tree species share the characteristics of pioneer and shade tolerant species.
Moreover, higher percentages (55%) of non-pioneer light demanding species are commonly found
based on the threshold values of three components of rarity (Association among environmental
range, frequency and density). In addition, 63% of tree species were rare in seven forms of rarity,
and 37% of tree species were commonly found in Ghanaian forest. In conclusion, non-pioneer light
demanding tree species have higher frequency and wider environmental range, whereas, shade
tolerant tree species have higher density. Overall, environmental factors have effect on the
frequency and density of woody species.
Keywords: Commonness; environmental range; rarity; threshold value.
species are not controlled by a single physical or
biotic factor, but by a complex of factors [9,10].
1. INTRODUCTION
Tropical forests are characterized by higher
number of tree species and diversity than
temperate forests. It is because of the historical
cause (higher speciation rates and more stable
environment in the tropics), and the better
options for maintenance of diversity. Moreover,
tropical rain forest represents the most diverse
and structurally complex forest in the world
[1,2,3]. Besides, tropical forests tend to be tall,
dense, and evergreen this leads to low light in
the forest floor. Therefore, light (canopy
openness) is the most limiting factor for the
establishment and growth of tropical rainforest
trees [4,5,6]. Variation in forest canopy structure
affects both understory light availability and its
spatial distribution. As a result, species
specialization (pioneers, intermediate and shade
tolerant species) could occur with respect to
conditions along the temporary environmental
gradients between the forest floors. This
environmental
gradient
determines
the
commonness and rarity of woody species.
Therefore, rain forests needs appropriate
intervention options and understanding of the
reasons that determines the commonness and
rarity of woody species. Previous studies stated
that rare species are rare in various ways [7,8].
Rabinowitz defined seven forms of rarity. A
species can be rare because 1) It has low
frequency (it occurs in a few plots) 2) It has a low
density (it has a few trees per ha) 3) It has a
narrow environmental range. Environmental
conditions and resource availability determine
species occurrence and their growth and
competitive interactions. The distribution of plant
Environmental variables such as, climatic
elements, edaphic factors, light availability, and
disturbance
affect
species
distribution,
abundance and frequency in the tropics
[2,4,11,12,13]. Consequently, plant species were
classified into three functional groups: Pioneers
(light demanding), non-pioneer light demanding
(NPLD) and shade tolerant species [14,15].
These functional groups have their own ability
and potential to distribute in the specific area.
Commonness and rarity vary among functional
groups. Rarity is broadly used to measure
extinction risk for conservation purposes
[8,16,17]. Studies in tropical forest indicated that
most tree species grow at low densities, i.e. <1
individual/ha for trees with > 10 cm DBH [18].
Pioneer species are thought to occur in a wide
range of environmental condition and effective
competitors [19] and more frequent and
abundant. In contrast shade tolerant species can
bear a narrower range of light condition, and
perhaps also a narrower range of soil and rainfall
conditions. This would result in a lower frequency
and abundance. However, information in relation
to frequency, density and environmental range of
each functional group in the Ghanaian forest is
lacking. Therefore, the aim of this study was to
understand the frequency, density and
environmental range of pioneer, NPLD and
shade tolerant species in the tropical forest zone
of Ghana to address the following research
questions:
2
Bayu et al.; JAERI, 10(4): 1-15, 2017; Article no.JAERI.30953
1) Do the three functional groups differ in one
or more aspects of rarity (frequency,
density
and
environmental
range)?
Hypothesis: pioneer species have wider
environmental range and higher frequency
but lower density compared to the other
two functional groups.
2) Do functional groups differ in the
proportion of species that can be classified
as rare? Hypothesis:
Pioneer species
would be more common in terms of
frequency, because they have better
capacity to disperse to new areas, and with
their opportunistic growth behavior.
3) How are measures of commonness and
rarity associated? (Frequency, density and
rainfall range)?
southwest to dry deciduous forest in the
northeast (the two driest forest types not
represented as forest reserves in these zones
are too small) [13]. At each grid intersection a 1ha plot was established in which trees were
inventorized in a nested design providing a total
number of 2205 plots. All living trees ≥ 30 cm
diameter at breast height (DBH) were sampled in
1ha plot, trees 10–30 cm DBH in 0.1-ha subplots
and trees 5–10 cm DBH in 0.05-ha subplots [14]
(Fig. 2). Totally, 258 species were identified and
categorized into three functional groups;
pioneers (66 species), non-pioneer light
demanders (62 species), and shade tolerant (130
species). Pioneers are defined as species that
are consistently established and grow in well
exposed area. Non-pioneer light-demanding
(NPLD) species tend to be shaded at small
diameters and illuminated when large, and
shade-tolerant species are found as young and
old plants in the shade [14,15]. Then after,
classification was made for rare species following
Rabinowitz classification method. Differentiating
common species from rare ones requires setting
arbitrary thresholds [7,8,21,22]. Threshold
density <1 individual/ha, were considered to be
rare for this study [18]. Similarly, we used mean
value for frequency (6.15%) and rainfall range
(601 mm) as a threshold to differentiate common
and rare species.
Hypothesis: A species that has wider
environmental tolerance have higher frequency
and higher density.
2. MATERIALS AND METHODS
2.1 Study Site
The study was undertaken in the tropical forests
of Ghana, West Africa. The forest in Ghana
covers an area of 4,939,958 ha (21.7% of total
land mass of Ghana). Annual rainfall ranges from
500 mm to 1750 mm and the mean daily
temperature in the forest zone ranges from about
25°C in the wet season and 27°C in the dry
season. There are seven main forest types.
These are: Moist evergreen, Wet evergreen,
Deciduous
Forest,
Coastal
Savannah,
Transitional Zone, Guinea Savannah, and Sudan
Savannah (Fig. 1). Wet evergreen forest is found
in the southwest and dry deciduous forest in the
northeast. The soils of the forest zone of Ghana
have been classified as latosols (cf [20]): old,
deeply weathered soils in which rock minerals
have been largely altered to kaolin and the
sesquioxides of iron and aluminium. Two major
types of latosols may be distinguished. Under
high rainfall strongly leached type (forest
Oxysols) and under low rainfall less strongly
leached soil (forest ochrosols) [16].
2.3 Data Analysis
First, we calculated for each species frequency
(the number of plots in which the species is
present) and the average density (the average
number of trees per plot, for the plot in which the
species is present) across the study area. To
evaluate whether the functional groups differ in
their frequency and density, a Kruskal-Wallis test
was done using species as data points. Pair-wise
differences between functional groups were then
tested using Mann-Whitney U tests. We used
chi-square (X2) analysis to test whether the
observed distribution of each functional group
differed from the expected distribution in their
frequency, density and environmental range
based on the threshold values of three
components of rarity. Correlation analyses were
done to assess the bivariate relationships
between different measures of commonness and
rarity (i.e., frequency, density and environmental
range). Besides, we did a multiple regression
analysis to evaluate to what extent commonness
and rarity is driven by the environmental range,
to the minimum or maximum environmental
conditions a species can tolerate.
2.2 Data Sources
A national forest inventory was made between
1986 to1991 by the Forestry Department of
Ghana in collaboration of with UK’s Overseas
Development Administration [14,15]. One
hundred twenty-seven forest reserves were
systematically sampled using a 2 km * 2 km grid.
These reserves cover most of the forest gradient
in Ghana from wet evergreen forest in the
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Bayu et al.; JAERI, 10(4): 1-15, 2017; Article
ticle no.JAERI.30953
Fig. 1. Forest Reserves in Ghana
na with selected abbreviated names including thos
ose mentioned
in the text [14]
Fig. 2. Showing inventoried reser
erves (except where too many overlap on the illus
ustration), with
an indication of the plot compos
osition as: [14] W: All plots Wet (/evergreen type)
e) of forest w:
Wet - Moist, most plots Wet wm:: Wet - Moist, most plots Moist M: All plots Moistt type
t
of forest
m: Moist - Dry, most plots Moist
st md:
m Moist - Dry, most plots Dry D: All plots Dry
y type
t
of forest
4
Bayu et al.; JAERI, 10(4): 1-15, 2017; Article no.JAERI.30953
shade tolerant species and 45% of the NPLD
species (Figs. 3, 4).
3. RESULTS
3.1 Frequency,
Density
Environmental Range of
Functional Group
and
Each
3.3 Association between Components of
Rarity
Frequency, density and environmental ranges
differed significantly among the functional groups
(Table 2). NPLD species had highest frequency
than the other groups. In addition, NPLD species
had the largest environmental range (rainfall and
soil fertility) followed by pioneer whereas; shade
tolerant species had the lowest range. In line with
this the proportion of rarity in each functional
group was determined. Based on the three
components of rarity NPLD species were
common in the study area (Table 1).
All measures of commonness and rarity were
significantly and positively related with each
other (Table 3). There is a strongly significant
positive correlation between density vs.
frequency and frequency vs. environmental
range (Table 3). When average density was
calculated based on all plots, then it was strongly
related to frequency but when the average
density was calculated based on the plots where
the species was present, then it was only
moderately related to frequency.
3.2 Aspects of Rarity
Functional Groups
The average density, based on all plots was
more determined by the environmental range
(soil and rainfall range) than the minimum or
maximum of soil fertility and rainfall (Table 3).
among
the
The percentage of rare species differed
significantly among the functional groups, both
when rarity was expressed in terms of frequency
2
2
2
(χ test, χ =25.22, DF=2, p<.001), density (χ
2
test, χ =9.01, DF=2, p=.01) or environmental
2
2=
test, χ 28.71, DF=2, p<.001).
range (χ
Generally, 74% of the pioneer species showed at
least one form of rarity, compared to 65% of the
The multiple regressions results show that
species that are more frequent do also have a
higher density (b=0.18, t=13.92, p<.001), and
that species with a wider soil and rainfall range
do have a higher frequency (soil range; p<.001
and rainfall range; P<.01).
Table 1. The number of tree species recorded in common and rare category depend on the
threshold values of the three components of rarity in the study area. The total number of
species were 258 (pioneer =66, non-pioneer light demander (NPLD=62 and shade
tolerant=130). Threshold density <1 individual/ha [18], frequency ≤6.15% and rain fall
range <601 mm were considered as rare species
Functional
groups
Pioneer
NPLD
Shade tolerant
Density (#/ha)
Rare
Common
<1
1≥ individual/ha
individual/ha
20
46
35
27
54
76
Frequency (%)
Rare
Common>
≤6.15%
6.15%
36
14
79
30
48
51
Rainfall range (mm)
Narrow
Wide
(<601 mm)
(≥601 mm)
32
13
81
34
49
49
Table 2. Differences in frequency, density and environmental range among the three
functional groups: pioneer (N=66 species), NPLD (N=62) and shade tolerant (N=130) species.
The Kruskal-Wallis test indicates differences among the three groups (p-value). Group means
followed by a different letters are significantly different between the functional groups (based
on pair-wise Mann-Whitney U tests)
P-value
Frequency (%)
Density (#/ ha-1) present plots
Rainfall range (mm)
Soil fertility range (%)
0.00
0.07
0.00
0.00
Pioneer
13.1 a
48.2 ab
565.7 b
64.3 b
5
Functional groups
NPLD
Shade tolerant
10.4 a
22.4 b
38.9 a
53.1 b
648.9 c
488.3 a
77.9 c
52.8 a
Bayu et al.; JAERI, 10(4): 1-15, 2017; Article no.JAERI.30953
Fig. 3. The percentage of rare and common species of each functional group based on frequency, density and rainfall range. The threshold values
for frequency <6.15%, density <1 individual/ha and rainfall range <601 mm were considered to be rare
Table 3. Pairwise correlation between the density, frequency, and environmental niche (minimum, maximum and range in rainfall and soil fertility)
of tropical tree species
Density (all plots)
Density (all plots)
Density (present plots)
Frequency (%)
R min
Rmax
Rrange
Smin
Smax
Srange
0.24
0.67
-0.18
0.32
0.34
-0.35
0.37
0.41
Density (present plots)
0.54
0.01
0.03
-0.03
-0.04
0.06
-0.02
-0.04
Frequency (%)
0.92
0.28
-0.35
0.47
0.56
-0.52
0.66
0.69
Rmin
-0.49
-0.11
-0.6
-0.1
-0.67
0.22
-0.71
-0.6
Rmax
0.76
0.21
0.74
-0.24
0.8
-0.88
0.48
0.71
Rrange
0.76
0.18
0.85
-0.62
0.87
-0.78
0.77
0.87
Smin
-0.78
-0.24
-0.8
0.28
-0.83
-0.77
-0.53
-0.78
Smax
0.73
0.18
0.84
-0.70
0.53
0.75
-0.58
Srange
0.8
0.21
0.9
-0.63
0.68
0.83
-0.77
0.95
0.94
*All Correlation values are significant at P<.01. (Rmin; rain fall minimum, Rmax; rain fall maximum, Rrange; rainfall range, Smin= Minimum soil fertility; Smax=maximum soil fertility and
Srange=soil range)
6
Bayu et al.; JAERI, 10(4): 1-15, 2017; Article no.JAERI.30953
Fig. 4. Relative abundance of tree species in each functional group based on Rabinowitz (1981) species classification (seven forms of rarity and
one in common category). Pioneer, intermediate (NPLD) and shade tolerant species respectively, (Common species =high frequency, high density,
high rainfall range; totally rare= low frequency, low density and low rainfall; two aspects of rarity is the combination of two low with one high
components of rarity, one aspects of rarity is the combination of two high and one low components of rarity)
7
Bayu et al.; JAERI, 10(4): 1-15, 2017; Article no.JAERI.30953
forests are dense and closed canopy (shaded
environment), which facilitates the establishment
of shade tolerant tree species. A Similar result
was found in panama rain forest 78% of species
were shade tolerant [24].
4. DISCUSSION
In this study we analyzed the distribution of
functional groups in their frequency, density and
environmental range and how measures of
commonness and rarity are associated in the
Ghanaian rainforest. In this section, we evaluate
the results with respect to the formulated
hypotheses and discuss their implications in the
context of tropical rainforest dynamics.
4.1 Frequency,
Density
Environmental Range of
Functional Group
4.2 Aspects of Rarity
Functional Groups
among
the
We hypothesized that pioneer species would be
more common in terms of frequency, because
they have better capacity to disperse to new
areas, and with their opportunistic growth
behavior they can tolerate a wide range of
environmental conditions, whereas, shade
tolerant species are more common in terms of
density, because the shaded conditions in
tropical forests are favorable for establishment.
In contrast, our findings showed that NPLD tree
species are more common than pioneer and
shade tolerant species in terms of frequency,
density and environmental range. This might be
due to NPLD tree species sharing both the
characteristics of pioneer and shade tolerant
species (Fig. 3). Due to this NPLD species
establish and grow both in light exposed and
shaded environment.
and
Each
Our result revealed that, NPLD species had
highest frequency than the other groups. In
addition, NPLD species had the widest
environmental range (rainfall and soil fertility)
followed by pioneer whereas; shade tolerant
species had the narrowest range. We
hypothesized that pioneer species have wider
environmental range and higher frequency but
lower density compared to the other two groups.
This is because, pioneer species are thought to
occur in a wide range of environmental condition
[20] and be more frequent than non-pioneers, but
because pioneers need gaps for their
establishment which are rare in tropical
rainforests (on average < 1 gap per hectare is
formed annually), they should have a low
density. But, it is surprising that, NPLD tree
species have wider environmental range and
higher frequency than the other groups, in
contrary with our hypothesis. Likewise, most
tropical tree species have intermediate light
requirements [4]. Perhaps this is because NPLD
tree species share the characteristics of pioneer
and shade tolerant species, and occurs in shade
and high light.
Overall, 37% of our species were categorized as
being super rare (i.e., they had low frequency,
and density, and a low environmental range),
and 37% were categorized as being super
common. Our finding indicates that each
functional group differs in one or more forms of
rarity. Most of NPLD tree species were
commonly found, whereas most of shade tolerant
species were extremely rare (Fig. 4). These
might be due to NPLD tree species have wider
environmental tolerance and very frequent than
shade tolerant species. Generally, 37% of the
studied species were commonly found and 37%
were extremely rare; whereas 26% were fell in
one or two aspects of rarity. 63% of tree species
fell into seven forms of rarity in this study. On the
contrary, [22] concluded that most tropical tree
species in the wet Amazon have wider
environmental tolerance and are habitat
generalist. This might be related with the
difference in environmental ranges used for this
study and the previous one [22]. Pitman et al.
[22] study in a narrow environmental range and
also used different definition for habitat
specialists compared to our study in which it was
carried out in a wider environmental gradient
(Ghana). This result suggested that it is difficult
to conclude about tropical forest with a specific
site study.
Correspondingly, Poorter et al. [23] show for
Liberian tree species that species that are shade
tolerant or light demanders throughout their life
are rare, and that most species have NPLD light
requirements and an ontogenetic increase in light
requirements over time. Therefore, NPLD tree
species may have
larger chance
for
establishment and growth and higher phenotypic
plasticity than others.
Density in all plots did not differ among the
functional groups, but when average density was
calculated based on the plots in which a species
is present then shade tolerant tree species had
higher density than pioneer and NPLD species.
This might be due to the fact that tropical rain
8
Bayu et al.; JAERI, 10(4): 1-15, 2017; Article
ticle no.JAERI.30953
and higher density (Fig. 5).
). The result
confirmed our hypothesis. Aligned
ed to this similar
studies confirmed that widespr
spread species
have higher frequency and abu
bundance than
species with restricted occurrenc
ence [25,26,27].
4.3 Association between Com
omponents of
Rarity
Our result showed that a speciess th
that has wider
environmental tolerance have high
igher frequency
Fig. 5. Scatter plots of the relation
ionship between density and frequency, and the ultimate
ul
effect
of environmental range (rain fall
ll a
and soil range) on the density and frequency off 258
2 Ghanaian
tree species; A) The relationship
hip between density and environmental range (rain
infall and soil
range); B) the relationship betw
etween frequency and environmental range (rainfa
fall and soil
range); C) The relationship betwe
een density and frequency. Regression lines and
d coefficient of
2
d
determination (R ) are shown
9
Bayu et al.; JAERI, 10(4): 1-15, 2017; Article no.JAERI.30953
Toledo et al. [28] reported that species density
was positively correlated with species frequency
in the tropical forest. In line with this [29] who
show that for western Amazonian tree common
trees at local scale have higher frequency and
density.
extremely rare, 37% of is commonly found;
whereas 26% of species fell in one and two
aspects of rarity. Overall, environmental factors
have an effect on the frequency and density of
woody species.
Finally, most of tree species are rare in one or
more forms of rarity, therefore, we suggest that
strong management incentives to conserve and
ensure sustainable management and thereby
safeguard for rare species in the Ghanaian
rainforest. For example; enrichment planting and
maintaining the existing rare tree species or
reducing forest disturbance and logging in the
area.
The distribution of plant species is mostly
explained by climatic variables and soil
conditions [27,29,30,31,32,33,34]. Our findings
also indicated that climatic variable and soil
condition significantly explain the distribution of
tree species in Ghanaian forest. A study by [31]
in the north-western Amazon found the same
result. On the contrary, [27] and [34] found
rainfall was the main driving factor for the
distribution of tree species.
COMPETING INTERESTS
5. IMPLICATION FOR CONSERVATION
Authors have
interests exist.
This study focused on the effect of environmental
variables on the frequency and density of
functional groups. Our results showed how
measures of commonness and rarity associated,
and which environmental variable affects the
frequency and density tree species. In addition to
this, we found which functional group was
commonly found and which one was rare. Thus,
this study gave information for which species will
be requiring conservation (Appendix 1, Table A,
B, C). These are 36% of pioneer, 14% of NPLD
and 49% of shade tolerant species in the study
area (Fig. 4). What can be done to conserve rare
species? Maintaining the prevailing rare species
in the area is good to maintain the existing forest.
In the long run, enrichment planting of the rare
species and provide
appropriate forest
management plan for the forest increases
dispersal agents, Ex-situ conservation and
germplasm conservation will be required to
maintain the forest ecosystem.
REFERENCES
6. CONCLUSION
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AND
1.
2.
3.
4.
5.
RECOMMENDA-
The results show that NPLD tree species have
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species that has wider environmental range have
higher frequency and density in the study area.
NPLD tree species are more common based on
the threshold values of three components of
rarity). Moreover, functional groups are
significantly different in one or more forms of
rarity. In general, 37% of tree species are
6.
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8.
9.
10.
10
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Bayu et al.; JAERI, 10(4): 1-15, 2017; Article no.JAERI.30953
APPENDIX
Appendix 1: List of 258 Ghanaian tree species in different forms of rarity in each functional
group.
Table A= Pioneer, Table B= NPLD, and Table C= Shade tolerant
Table A. List of 66 Ghanaian pioneer tree species in three forms of rarity and common
category in the study area
Pioneer
Totally rare species
Alchornea cordifolia
Allophylus africanus
Antidesma membranaceum
Bersama abyssinica
Two aspects of rarity
Cussonia bancoensis
Ehretia trachyphylla
Holarrhena floribunda
Maesopsis emini
One aspects of rarity
Nauclea diderrichii
Terminalia ivorensis
Lophira alata
Holoptelea grandis
Bridelia atroviridis
Millettia zechiana
Psydrax parviflor
Psydrax subcordata
Chaetachme aristata
Clausena anisata
Pteleopsis hylodendron
Rauvolfia vomitoria
Shirakiopsis elliptica
Tetrorchidium
didymostemon
Vernonia conferta
Voacanga Africana
Rhodognaphalon
brevicuspe
Bombax buonopozense
Elaeis guineensis
Erythroxylum mannii
Margaritaria discoidea
Cola digitata
Cordia senegalensis
Croton penduliflorus
Cuviera macroura
Diospyros abyssinica
Dracaena arborea
Elaeophorbia grandifo
Solanum erianthum
Harungana
madagascariensis
Pouteria alnifolia
Morinda lucida
Spathodea campanulata
Vernonia amygdalina
Vismia guineensis
Carica papaya
Newbouldia laevis
Stereospermum
acuminatissimum
Tetrapleura tetraptera
Trema orientalis
Zanthoxylum gilletii
Common species
Triplochiton scleroxylon
Celtis adolfi-friderici
Morus mesozygia
Petersianthus
macrocarpus
Terminalia superba
Alstonia boonei
Baphia pubescens
Ceiba pentandra
Cleistopholis patens
Cola caricifolia
Discoglypremna
caloneura
Hannoa klaineana
Lannea welwitschii
Monodora tenuifolia
Musanga cecropioides
Ricinodendron
heudelotii
Sterculia tragacantha
Note: (Common species means a species that have highest frequency, highest density, grow in wider rainfall range; totally rare
a species that have lowest frequency, lowest density and grow in narrow rainfall range; two aspects of rarity is the combination
of two low with one high components of rarity, one aspects of rarity is the combination of two high and one low
components of rarity)
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Bayu et al.; JAERI, 10(4): 1-15, 2017; Article no.JAERI.30953
Table B. List of 62 Ghanaian NPLD tree species in three forms of rarity and one common
category
NPLD
Totally rare species
Pericopsis elata
Two aspects of rarity
Balanites wilsoniana
One aspects of rarity
Entandrophragma utile
Albizia glaberrima
Dialium dinklagei
Tieghemella heckelii
Anisophyllea meniaudii
Anthonotha fragrans
Kigelia africana
Majidea fosteri
Aubrevillea kerstingii
Cassipourea gummiflua
Hildegardia barteri
Placodiscus
bancoensis
Stemonocoleus
micranthus
Okoubaka aubrevillei
Lovoa trichilioides
Entandrophragma
candollei
Mansonia altissima
Albizia adianthifolia
Albizia furruginea
Anopyxis klaineana
Canarium schweinfurthii
Antrocaryon micraster
Duboscia viridiflora
Lonchocarpus sericeus
Ongokea gore
Ophiobotrys zenkeri
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Common species
Enthandrophragma
angolense
Enthandrophragma
cylindricum
Khaya ivorensis
Heritiera utilis
Piptadeniastrum africanum
Antiaris toxicaria
Guibourtia ehie
Albizia zygia
Distemonanthus
benthamianus
Pycnanthus angolensis
Sterculia rhinopetala
Amphimas pterocarpoides
Bussea occidentalis
Chrysophyllum perpulchrum
Cola millenii
Corynanthe pachyeras
Funtumia africana
Funtumia elastica
Homalium tetestui
Irvingia gabonensis
Klainedoxa gabonensis
Duguetia staudtii
Parinari excels
Parkia bicolor
Pentaclethra macrophylla
Phyllocosmus africanus
Pterygota macrocarpa
Sterculia oblonga
Treculia africana
Trichilia monadelpha
Trichilia prieureana
Trichilia tessmanni
Trilepisium
madagascariense
Xylia evansii
Bayu et al.; JAERI, 10(4): 1-15, 2017; Article no.JAERI.30953
Table C. List of 130 Ghanaian shade tolerant species in three forms of rarity and one common
group
Shade tolerant
Totally rare species
Aeglopsis chevalieri
Afrostyrax lepidophyllus
Two aspects of rarity
Antidesma laciniatum
Chrysophyllum pruniforme
Anonidium manni
Aporrhiza urophylla
Chrysophyllum subnudum
Coula edulis
Aptandra zenkeri
Berlinia tomentella
Breviea sericea
Diospyros mannii
Discoclaoxylon hexandrum
Garcinia kola
Borassus aethiopicum
Broussonetia papyrifera
Cassipourea congoensis
Cedrela odorata
Chrysophyllum beguei
Citropsis gabunensis
Crudia gabunensis
Grossera vignei
Isolona campanulata
Picralima nitida
Piptostigma fasciculatum
Scaphopetalum amoenum
Strephonema pseudocola
Vitex grandifolia
Cynometra megalophylla
Dasylepis assinensis
Dasylepis
brevipedicellata
Dialium guineense
Dictyandra arborescens
One aspects of rarity
Berlinia confuse
Cylicodiscus
gabunensis
Cynometra ananta
Diospyros sanzaminika
Drypetes pellegrinii
Glyphaea brevis
Scytopetalum tieghemii
Common species
Aidia genipiflora
Annickia polycarpa
Anthonotha macrophylla
Aulacocalyx jasminiflora
Baphia nitida
Buchholzia coriacea
Calpocalyx
brevibracteatus
Carapa procera
Chidlowia sanguinea
Cleidion gabonicum
Cola chlamydantha
Cola nitida
Copaifera salikounda
Craterispermum
caudatum
Dacryodes klaineana
Dialium aubrevillei
Diospyros kamerunensis
Drypetes principum
Greenwayodendron
oliveri
Guarea cedrata
Guarea thompsonii
Hexalobus crispiflorus
Hymenostegia afzelii
Lecaniodiscus
cupanioides
Leptaulus daphnoides
Maesobotrya barteri
Mammea africana
Mareya micrantha
Microdesmis puberula
Millettia rhodantha
Monodora myristica
Diospyros canaliculata
Diospyros gabunensis
Diospyros heudelotii
Diospyros mespiliformis
Diospyros monbuttensis
Diospyros soubreana
Diospyros viridicans
Garcinia afzelii
Garcinia epunctata
Hymenostegia aubrevillei
Hymenostegia gracilipes
Omphalocarpum
pachysteloides
Lasiodiscus mannii
Leptonychia pubescens
Lychnodiscus
dananensis
Lychnodiscus reticulatus
Myrianthus arboreus
Myrianthus libericus
Napoleonaea vogelii
Nesogordonia
papaverifera
Octoknema borealis
Panda oleosa
Pentadesma butyracea
Protomegabaria
stapfiana
Scottellia klaineana
Strombosia glaucescens
Synsepalum afzelii
Turraeanthus africanus
Xylopia staudtii
Xylopia villosa
Maerua duchesnei
Mallotus oppositifolius
Manilkara obovata
Massularia acuminata
Mischogyne elliotiana
Mischogyne elliotiana
Newtonia aubrevillei
Newtonia duparquetiana
Olax subscorpioidea
Oxyanthus pallidus
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Bayu et al.; JAERI, 10(4): 1-15, 2017; Article no.JAERI.30953
Shade tolerant
Totally rare species
Oxyanthus speciosus
Oxyanthus unilocularis
Pausinystalia lane-poolei
Pellegriniodendron
diphyllum
Piptostigma fugax
Pycnocoma macrophylla
Robynsia glabrata
Smeathmannia
pubescens
Soyauxia grandifolia
Soyauxia velutina
Synsepalum aubrevillei
Talbotiella gentii
Tapura fischeri
Tapura ivorensis
Tectona grandis
Uvariastrum pierreanum
Uvariodendron
angustifolium
Uvariodendron
occidentale
Vitex doniana
Two aspects of rarity
One aspects of rarity
Common species
_______________________________________________________________________________
© 2017 Bayu et al.; This is an Open Access article distributed under the terms of the Creative Commons Attribution License
(http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium,
provided the original work is properly cited.
Peer-review history:
The peer review history for this paper can be accessed here:
http://sciencedomain.org/review-history/17924
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