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Floral Diversity of Aquatic Macrophytes in Two Water Bodies in
Ekiti State, Nigeria.
Agunbiade, R.O
1
, Edward, J.B*
1
, Adegbola, M.A
1
, Adeojo, L.O
1
, Ajayi E.D
2
.
1
Department of Zoology, Ekiti State University, P.M.B.5363, Ado-Ekiti, Ekiti State, Nigeria.
2
Dept. of Statistics, Ekiti State University, P.M.B.5363, Ado-Ekiti, Ekiti State, Nigeria.
*Corresponding Author
DOI: https://doi.org/10.51584/IJRIAS.2025.100900070
Received: 11 Sep 2025; Accepted: 18 Sep 2025; Published: 17 October 2025
ABSTRACT
This study was aimed at investigating the macrophytes composition and species diversity of Rivers Osun and
Elemi, located at Ikere and Ado- Ekiti, respectively. Macrophyte samples were collected from both rivers
between between the months of May to October, 2023. Nineteen (19) species of macrophytes were collected
from each of the two rivers. Osun River had a total number of 730 macrophytes with a percentage relative
abundance of 48% while Elemi River had a total number of 794 macrophytes with a percentage relative
abundance of 52%. In River Osun, Solenastemon monostachyus was the most abundant (145) and had the
highest percentage relative abundance of 19.86% while Coix larcryma-jobi was the least abundant (8) species
with a percentage relative abundance of 1.01%. In Elemi River, Alternanthera brasiliana was the most
abundant (212) macrophytes species with a percentage abundance of 26.70% while Lepistemon owarianse was
the least abundant (7) species with a percentage relative abundance of 0.88%. The diversity indices showed
that macrophytes at River Elemi had the highest diversity index (H’= 3.48) and species richness (d = 2.73). It
was also noted that macrophyte at River Elemi had the highest evenness index (E’= 1.18). This study also
revealed that macrophytes at River Osun had the highest Menhinick index (MH = 0.70) and Simpson index (1-
D = 0.91). The dominant macrophytes in both study areas are pollution-tolerant species, and the rivers have
been impacted by nutrient enrichment. Hence, both rivers should be adequately monitored and measures put in
place to checkmate further enrichment and prevent pollution as macrophytes have been obersved to play
significant roles in community-based conservation strategies, effluent control, and policy implications for
freshwater biodiversity conservation.
Keywords: Diversity, Abundance, Macrophytes, River Elemi, River Osun.
INTRODUCTION
Aquatic macrophytes are diverse groups of naked aquatic photosynthetic organisms including green algae
(Chlorophyta), yellow-green algae (Xanthophyta) and red algae (Rhodophyta), cyanobacteria (Blue Green
Algae), mosses and liverworts (Bryophytes), ferns (Pteridophytes) and seed bearing plants (Spermatophytes).
Macrophytes are important in providing food and habitats for aquatic invertebrates, zooplankton, fishes and
aquatic wild life (Lacoul and Freedman, 2016). They are important components of the aquatic ecosystem
because they enhance the physical structure of habitats and biological complexity which increases biodiversity
within the littoral zones (Wetzel, 2016, Pelicice et al., 2018). In addition both live and dead materials (detritus)
from aquatic macrophyte may serve as food resources for aquatic and terrestrial organisms. The study of
aquatic macrophyte is an essential component of understanding a water body due to its important ecological
role and its ability to characterize the water quality. Aquatic macrophytes can be efficient indicators of water
quality and their presence may enhance water quality due to their ability to absorb excess load of nutrients
(Shristhi and Suman, 2020). When the aquatic plants died, they are partially decomposed in detritus and
primarily consumed by invertebrates, insects and larger crustacean (Madsen, 2019). Macrophytes are also used
as agents in bioremediation (Wood and McAtamney, 1993; Nirmal et al., 2008; Aloke et al., 2022;
Seenivasagan et al., 2022). The study environments are pristine in nature. No industrial discharge or serious
agricultural waste inputs were observed around the two rivers, except municipal runoffs during the rainy
INTERNATIONAL JOURNAL OF RESEARCH AND INNOVATION IN APPLIED SCIENCE (IJRIAS)
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Page 701
season. Absolutely few research work has been carried out on them, hence the need for this study. The study
was carried out to survey the diversity and distribution pattern of aquatic macrophytes in two water bodies
(River Elemi in Ado-Ekiti and River Osun in Ikere-Ekiti) in Ekiti State.
Materials and Method
Study Areas
The study was carried out in River Osun located in Ikere Ekiti and Elemi River in Ado-Ekiti, Ekiti State. River
Osun is the major river of this town. This area is generally characterized by both raining and dry season.
Raining season runs from April to November while the dry season runs from December to March. Ikere- Ekiti
has a population of 148,558 (NPC, 2006). Activities around the river include farming, car washing, block
industry and indiscriminate dumping of refuse beside the river.
River Elemi is a flowing river that has tributaries running across many different paths within Ado-Ekiti.
However, this study site is located at Bawa along Iworoko Ekiti road in Ado local government area of Ekiti-
State. The river takes its source from River Elemi in Igede-Ekiti which itself was said to take its source from
the popular Osun River in Oshogbo, Osun State. The river is subjected to effluent discharges from various
sources including mechanic workshops and some businesses cited along its banks. Other activities around this
river are lumbering, dredging for sand and domestic sewage inputs, which may lead to wide scale pollution of
the river.
Collection and Identification of Macrophytes.
A quadrat of 1x1m
2
(Goswami et al., 2014) was laid across each randomly selected sampling point. All
emergent and floating plants within the quadrat frame were hand picked, cleaned and identified. The
collection was done for a period of six months. In deep areas a sampling rake was use to bring plants up from
the bottom. The identification was made using a hand book of common aquatic plants of the Kainji Lake,
Nigeria (Obot and Ayeni, 1987) and (Annelise et al., 2004) and recorded as described by (Nedungadi et al.,
2013).
Statistical Analysis
Biodiversity indices were calculated using abundance and relative abundance of macrophytes species as well
as the use of other standard formulas. Diversity of macrophytes species at all study areas was calculated using
Shannon-Weaver diversity index (H). The Shannon index is given by the formula below; -
H = -Ʃpilnpi
Where pi = S/N, S is the total number of individuals of one species, N is the total number of all individuals in
the sample and ln = logarithm to base e. The proportion of species relative to total number of species (pi) was
calculated, and multiplied by natural logarithm of this proportion (ln pi). The results were summed across the
species, and multiplied by -1.
Species richness of macrophytes was calculated using the Margalef index (D). The index is given by the
following formula
Margalef Index (ml) =
Where S is the total number of species, N is the total number of individuals in the sample and ln is the natural
logarithm (logarithm to base e).
Menhinick Index (Mh) =
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Where S is the total number of species, N.
RESULTS
Macrophytes Composition of Study Stations
The macrophytes species encountered in the various study areas are shown in Tables 1 and 2 for River Osun
and Elemi River respectively. A total of 1524 macrophytes, 38 species were recovered from River Osun and
Elemi River. Figure 1 showed that Osun River had a total number of 730 macrophytes with a pecentage
relative abundance of 48% while Elemi River had a total number of 794 macrophytes with a pecentage relative
abundance of 52%. Both study areas recorded equal number of species (19) during the course of this study.
The populations of the various species are shown in Table 1 and for River Osun and Elemi River.
Table 1-2 and Figure 2-3 showed the abundance and relative abundance of Macrophytes in each study area. In
Osun River, Solenastemon monostachyus was the most abundant (145) and had the highest pecentage relative
abundance of 19.86% while Coix lacoyma-jobi was the least abundant species (8) with a pecentage relative
abundance of 1.10%. The table also showed that in Elemi River, Alternanthera brasiliana was the most
abundant macrophytes species (212) with a pecentage abundance of 26.70% while Lepistemon owarianse was
the least abundant species (7) with a pecentage relative abundance of 0.88%.
Species
Abundance
Relative Abundance
Pennisetum purpureum
19
0.03
Corchorus aestuans
81
0.11
Solenastemon monostachyus
145
0.20
Adenostemon perrottetii
77
0.11
Laportea aestuans
14
0.02
Asyrtaria gangetica
24
0.03
Ageratum conyzoides
31
0.04
Coix lacryma-jobi
8
0.01
Ludwigia octovalvis
32
0.04
Acacia ataxacantha
25
0.03
Melanthera scandens
11
0.02
Lepistemon owariense
57
0.08
Ipomoea hederifolia
9
0.01
Dactyloctenium aegyptium
30
0.04
Sporobolus pyramidalis
15
0.02
Desmodium aescendes
67
0.09
Tridax procumbens
53
0.07
Trema orientalis
19
0.03
Setaria megaphylla
13
0.02
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Table 1. Relative Abundance of Macrophytes in Osun River Ikere -Ekiti, Ekiti- State.
Fig. 1: Percentage Relative Abundance of Macrophytes in Osun River
Table 2. Relative Abundance of Macrophytes in Elemi River Ado-Ekiti,Ekiti-State.
Species
Abundance
Spilanthus filicaulis
32
Pennisetum purpureum
57
Scleria verrucosa
18
Alternanthera brasiliana
212
Tithonia diversifolia
51
Luffa cylindrical
17
Synedrdla nodiflora
19
Vernonia galamensic
17
Ipomoea involucrata
25
Panicum maximum
8
Chamaecrista mimosoides
11
Asystasia gangetica
71
Ageratum conyzoides
65
Ludwigia decurrens
23
Sida garckeana
96
Total
730
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Adenostemma perrottetii
11
Lepistemon owarianse
7
Ipomoea spp
35
Hewitia sublobata
19
TOTAL
794
Fig. 2: Pecentage Relative Abundance of Macrophytes in Elemi River
Fig. 3. Comparative Abundance of Macrophytes in Osun and Elemi River
Figure 4. Species Population of Macrophytes Composition of Osun River, Ikere-Ekiti
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Figure 5. Species Population of Macrophytes Composition of River Elemi
Alpha Diversity Indices in the Various Study Areas
Alpha diversity indices in the two study areas are shown in Table 3 and Figures 4. The diversity indices
showed that macrophytes at Elemi River had the highest diversity index (H’= 3.48) and species richness (d =
2.73). It was also noted that macrophytes at River Elemi had the highest evenness index (E’= 1.18). The study
also revealed that macrophytes at River Osun had the highest Menhinick index (MH = 0.70). And River Osun
had the highest Simpson index (1-D = 0.91).
Table 3. Alpha Diversity Indices for the study areas
Parameters
Osun River
Elemi River
No. of species
19
19
Shannon H
3.15
3.48
Evenness
1.07
1.18
Simpson 1-D
0.91
0.89
Margalef
2.73
2.70
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Menhinick
0.70
0.67
Figure 6. Alpha Diversity Indices for the study areas
Pictures of some macrophytes collected during the study
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Plate 9: Ipomoea involucrate (Convolvulaceae)
DISCUSSION AND CONCLUSION
The macrophytes in the Osun and Elemi Rivers were the subject of this investigation. The most prevalent
macrophyte species in the Elemi River was Alternanthera brasiliana, whereas Solenastemon monostachyus
dominated the Osun River. The presence of diverse physical and physiological characteristics in this plant
species may be the cause of this family's dominance. This may include the capability to change surroundings
by altering the nature of fire and animal herbivory, effective long-distance dispersal, successful establishment
biology, ecological flexibility, and resilience to disturbance (Linder et al., 2018).
The most emergent macrophytes were found among growth forms, which is a sign of the disruption produced
by varied anthropogenic activities in the riparian zone of the rivers. The fact that emergent species have the
highest species diversity and the lowest free-floating species indicates that species richness increases as water
level drops (Sharma and Singh, 2017), Roka (2019) and Dongol et al. (2014) all came to the same conclusion.
Elemi River's highest species composition may be caused by anthropogenic disturbance, mild riparian erosion,
and riparian disturbance. The river's amount of water may also be to blame. Zerlin and Henry (2014) found a
similar outcome.
Low primary plant production due to mechanical stress from river water circulation may also result in fewer
species of macrophytes in rivers than in lakes. According to Rui et al. (2013), the river's discharge regime and
flow velocity limit the growth of diverse aquatic plants in the river channel's interstices. Another crucial
element that promotes roots and the formation of macrophyte communities is a stable substrate (Haslam,
2006).
CONCLUSION
Aquatic plants have a significant role in the environment of rivers. They are the main producers, support
animal habitats, and maintain sediment. Aquatic plants can be used to identify a variety of anthropogenic
influences. Additionally, the presence of aquatic plants in every aquatic ecosystem has a significant impact on
water quality. Human activities in the area also have an impact, as was seen in the study sites. The species of
aquatic macrophytes that are present there are also influenced by the physical and chemical characteristics of
the water body and the type of soil surrounding it. Macrophytes in the river when properly checked, help as
substrate ground, feed and habitat for aquatic animals, hence there is a need to monitor the growth of the
macrophytes of these two rivers at regular intervals. It was observed that in Osun River, Solenastemon
monostachyus was the most abundant, while in Elemi River, Alternanthera brasiliana was the most abundant
macrophytes species. The dominant macrophytes in both study areas are pollution-tolerant species, and the
rivers have been impacted by nutrient enrichment. This study has provided baseline information on the
diversity of macrophytes of the two rivers.
REFERENCES
1. Lacoul P, Freedman B. (2016). Environmental influences on aquatic plants in freshwater ecosystems.
Environ. Rev. 14:89-136.
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ISSN No. 2454-6194 | DOI: 10.51584/IJRIAS |Volume X Issue IX September 2025
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2. Linder, H.P., Lehmann, C. E., Archibald, S., Osborne, C. P.,& Richardson, D.M. (2018). Global grass
(Poaceae) success underpinned by traits facilitating colonization, persistence and habitat
transformation. Biological Reviews. 93(2), 1125-1144.
3. Aloke, S., Pronoy, M., Koyel, R., Koushik, S. and Tanmay, S. (2022). A review on phyto-remediation
by aquatic macrophytes: A natural promising tool for sustainable management of ecosystem. Int. J. Exp.
Res., Vol. 27: 9-31.
4. Annelise G., Carina J.C., Carina V.G., and Rene G. (2004). Easy Identification of Aquatic Plants: a
guide for the identification of water plants Department of Water Affairs and Forestry, South-African
National Botanical Institute.
5. Devlin, R.M. (2017). Plant Physiology. Reinhold, New York. pp564.
6. Dvorak J. (2016). An example of relationship between macrophytes, macro invertebrates and their food
resources in a shallow eutrophic lake. Hydrobiologia. 339:27-36.
7. Goswami, G., Pal, S., and Palit D. (2014). Studies on the physico-chemical characteristics, macrophyte
diversity and economic prospect in Rajmata Dighi: a wetland in Cooch Behar Distict, West Bengal,
India. NeBio 1 (3), 21-27
8. lake contamination by accumulation of trace elements in selected aquatic macrophytes: a case study of
Kanewal Community Reserve, Gujarat, India.
9. Madsen, J.D. (2019). Impact of invasive aquatic plants on aquatic biology. In: Biology and Control of
Aquatic Plants: A Best Management Practices Handbook, edited by LA Gettys, WTHaller and M
Bellaud. pp1-8.
10. McQueen, D.J, Post, J.R, Mills, E.L. (2016). Trophic relationship in freshwater pelagic ecosystems.
Canadian Journal of Fisheries and Aquatic Sciences. 43:1571-1581.
11. Nedungadi, P., Raman, R., and McGregor, M. (2013, October). Enhanced STEM learning with Online
Labs: Empirical study comparing physical labs, tablets and desktops. In Frontiers in Education
Conference 1585- 1590.
12. Nirmal K. J.I., Soni, H., Kumar, R.N., (2008). Evaluation of biomonitoring approach to study
13. Obot, E.A. and J.S.O. Ayeni, 1987. A Handbook of Common Aquatic Plants of the Kainji Lake Basin,
Nigeria. Kainji Lake Research Institute/Saolog Printing Production, Ilorin, Nigeria.
14. Pelicice F.M, Thomas SM, Agostinhno AA. (2018). Simple relationships to predict attributes of fish
assemblages in patches of submerged macrophytes. Neotrop Ichthyol. 6 (4): 543-550.
15. Roka, D. (2019). Seasonal variation of Macrophytes and Phytoplankton Diversity at Shoreline of
Beeshazar Lake, Chitwan, Central Nepal. M.Sc. Dissertation submitted to Central Department of
Botany, Tribhuvan University, Kathmandu, Nepal.
16. Rui, L., Qiujin, X., Sheng, Z.G., Ying, C.X., & Sai, B. (2013). Effects of various total dissolved solids
(TDS) on the growth of Phytoplankton. Research on Environmental Sciences, 26(4), 1072-1078.
17. Seenivasagan, R., Karthika, A., Kalidoss, R., & Malik, J. A. (2022). Bioremediation of Polluted
Aquatic Ecosystems Using Macrophytes. In Advances in Bioremediation and Phytoremediation for
Sustainable Soil Management: Principles, Monitoring and Remediation (pp. 57-79). Springer
International Publishing. https://doi.org/10.1007/978-3-030-89984-4_4
18. Sharma, R.C., & Singh, S.(2017). Macrophytes of Sacred Himalayan Lake Dodi Tal, India:
Quantitative and Diversity Analysis. Biodiversity International Journal 1(4), 137-144.
19. Solak C.N, Barinova S, Acs E, Dayioglu H. (2012). Diversity and ecology of diatoms from Felent
creek (Sakarya river basin), Turky. Turkish Journal of Botany. 36:191- 203.
20. Wetzel, R. G. (2018). Limnology: Lake and River Ecosytem. Academic San Diego, California, U.S.A.
234Pp.