INTRODUCTION 

Wetlands are renowned for their ecosystem services such as purifying polluted water, remediating storm water and supporting diverse wildlife communities. It is therefore referred to any geographical area with characteristics of both dry land and bodies of water [1]. A Wetland is a terrestrial habitat in which the soil is saturated with moisture either permanently or seasonally such areas may also be covered partially or completely by shallow pools of water [2]. The physicochemical properties of wetlands  vary widely in accordance with the multiplicity and diversity of environmental ,litho logical and pedogenetic factors with which the wetlands are associated [3].This implies that wetlands are characterized by certain water regimes , plant species and soil characteristics [4]. .In most cases the water level in wetlands called the water table is usually at above or just below the  soil surface for enough time to restrict the growth of plants to those adapted to wet condition and promote the development of soil characteristics  of  wetland environment [2].  

Soil microorganisms play crucial roles in various biogeochemical processes [5], facilitating the decomposition of excess nutrient in wetland ecosystems under both aerobic and anaerobic soil conditions and are the foundation of the wet ecosystems [5]. Studies have shown that microbial nitrification and denitrification processes regulate about 80-90 % of the total nitrogen in wetlands.. In addition phosphorus accumulating organisms may absorb phosphate from wastewater under alternating aerobic and anaerobic conditions [6]. However, the nutrient removal as well as other ecosystem functions of wetlands can differ due to factors that alter physicochemical  properties  and  microbial compositions [6]. 

Factors such as soil depth gradients, water depth, soil organic carbon  and nitrogen concentrations, soil water contents and pH  can substantially influence microbial communities [7], .In addition soil microbial communities are likely to shift  over time, as the soil total organic  carbon in wetlands  may gradually increase with wetland age. Therefore understanding the composition  and diversity of microbial communities  and their relationships with environmental characteristics that shape this ecosystem   is  necessary [9].

Wetland soils constitute vast underexploited and sometimes undiscovered ecologies in many countries including Nigeria. The acidic nature of the wetlands soils can influence the soil biological community; a consequence of the acidic nature  of the parent rock  and the influence of the leached profile  under high annual rainfall condition. Studies have shown that wetland soils have considerable agricultural potentials for the production of rice, maize, dry season vegetables   cocoyam and early yam species [10-11].  Wetland serves as transition between terrestrial and aquatic ecosystems, therefore functions as buffers for terrestrial runoff thereby preventing eutrophication of inland as well as  coastal waters. Wetland is essential for hydrological and ecological process and the area supports a rich floristic diversity and fauna. Wetland also serves as a water filter nutrients and sediments  are abundant  and that makes  it possible  for many species to live  [12]. The close proximity of oxic-anoxic conditions  in this area often created by  the wetland plant roots  facilitates the simultaneous  activity of aerobic  as well as anaerobic  microbial activities . Wetland soils possess unique physicochemical characteristics, including high moisture content, abundant organic matter, fluctuating redox conditions, and varying nutrient availability [13]. These properties can significantly influence the nutritional and anti-nutritional composition of plants and fruits grown in such environments. The notational properties of plant have greater potentials on human health [14 15]. 

Wetlands receiving industrial effluents, agricultural runoff, or urban wastes may contain elevated concentrations of toxic metals, including lead (Pb), cadmium (Cd), mercury (Hg), and arsenic (As). These metals can be absorbed and accumulated by plants and subsequently enter the human food chain through consumption [16]. The bioaccumulation of these contaminants may adversely affect human health [17], leading to various toxicological effects depending on the level and duration of exposure [18-20].

MATERIALS AND METHODS

SAMPLE COLLECTION

Soil samples were collected from two depths (0-15cm and 15- 30 cm ) from four  locations/ sites   (A,B,C,D.)  in Itu, Akwa Ibom State. The soil samples were collected using methods of Anderson and Ingram [21] during the wet and dry season into labeled sterile polythene bags and taken in ice packed coolers to the laboratory for microbiological analysis

MICROBIOLOGICAL ANALYSIS

Serial Dilution 

Tenfold serial dilution of the soil samples were made using standard methods 

Inoculation and Incubation 

One milliliter of appropriate tenfold serial dilutions of the soil samples was inoculated onto nutrient agar (Oxoid CM 314) in five replications using  pour plates  method . Inoculated  plates were  incubated  at 28 ± 2^oC   for 18 – 24 hours    at  32^oC  for the enumeration  of  total heterotrophic  bacteria count  Visible  discrete colonies in incubated  plate  were  counted  using colony counter and expressed as colony forming unit per gramme  (Cfu/g )  of soil sample. The organisms were identified using  gross morphology  Gram staining reaction  and biochemical tests . Data obtained for bacterial counts was analyzed using Analysis of Variance (ANOVA) with Duncan’s New Multiple. Range test used to separate significant means at 5% level. 

Maintenance of Pure Culture 

Discrete colonies were purified by repeated subculture  unto  nutrient   agar  . Pure cultures were preserved on nutrient agar slants  and stored in the refrigerator  ( 4⁰C ± 2⁰C)  at ambient temperature  ( 28⁰C ± 2⁰C ) for further  analysis . 

Characterization and identification of   Bacterial  Isolates

The pure bacterial strains were identified using gross morphology,  Gram staining reaction  and biochemical tests  including  carbohydrate  utilization [22].  Identification of bacterial isolates  was accomplished by comparing  the characteristics of the cultures with that of a known taxa as in  Domsch et al., [23].

RESULTS AND DISCUSSION

The result of the total heterotrophic bacteria count  obtained in this study  ranged from 1.10 x 10⁶ – 1.67 x10⁶ Cfu/g and a significant difference  (P ≤ 0.05) in bacterial  loads present in four study  area . The distribution of these organisms in the soil of study is presented in Table 1.0 .The results showed high bacterial counts in the area close to the water bodies with high amount of organic matter. The bacteria isolates were Bacillus cereus, Staphylococcus aureus , Enterobacter aerogenes, Pseudomonas aeruginosa ,  Escherichia coli, Proteus vulgaris and Klebsiella pneumoniae. Similar observations were reported by Udotong et al. [13], who observed higher bacterial populations in wetland soils with elevated organic matter content.

The occurrence and abundance of bacteria obtained in this study is shown in Table 1. The location that shows high bacteria count was the one  near  the body of water  (River).This shows that the conservation state  of the area  is at risk as  most of the decomposers were found deep in the subsoil  as distribution  of nutrient and microorganisms is related with the variations in organic carbon ,clay content and soil  water characteristics  at the field scale .  Moreover, Perz and Restrepo,(2008) reported that  ,water from such type of wetland is not bacteriologically safe for human consumption.  The bacteria species   identified  were grouped into 6-7species . Out of this, 64 % were Bacillus species,12% were species of E. coli , Klebsiella sp ( 10 %),  Pseudomonas sp (8%)  and Enterococcus (6%). Location A had the highest bacterial counts followed by Location C while location B  had the least.   The distribution of total heterotrophic bacteria count with depth revealed that 0-15 cm had the highest count in all the locations. This is due to the fact that surface soil had higher biomass population   than the sub soil  as reported by Akpan and Ayegba, [24].  

Bacterial community in the soil of Itu wetland can degrade several types of organic compound      [13], [25].  The relative occurrence of  these degrading  bacteria in Itu wetland soil  provides a good surface for agricultural activities .The presence of different bacteria species in Itu wetland soils  have indicated the relative  significance of the soil sustaining  floral diversity despite being useful in bioremediation of pollutants reported by Macaulay [26].The presence Enterococcus spp  in the wetland soil in  Itu is in line with the findings of Akpan and Ayegba. [24], and Udotong et al., [13] who reported Klebsiella among the predominant soil inhabiting  bacteria in Eket  wetland in Nigeria . However, the bacterial species identified in Baturiya  wetland  differed from the ones identified by Ballesteros et al., [27]  from some wetland in Columbia . This differences could be as a result of variation in climate change and edaphic factors in the study area .Therefore organic matter degrading bacterial species are ubiquitous in many environments [28]. Diversity of microorganisms is a key factor for soil structure, fertility and microbial metabolism and these were identified in this study.

The diversity of bacteria in the wetland soils of Itu highlights the ecological importance of these environments as reservoirs of microbial communities. The high bacterial abundance and diversity observed in the wetland soils of Itu demonstrate the widespread distribution of microorganisms in natural environments and their ability to thrive under varying ecological conditions [5], [29]. The bacterial diversity observed in the wetland soils of Itu reflects the ecological richness of the environment and its capacity to support a wide range of microbial species [30-31], the occurrence of diverse bacterial populations in wetland soils, water, fish samples and waste dumpsite  suggests that environmental reservoirs such as wetlands may influence the microbial communities [5] [9], [25

The occurrence of bacterial species with known biodegradation potentials further suggests that the wetland possesses natural capacity for the attenuation of organic pollutants and environmental contaminants [32]. Therefore, the conservation and sustainable management of these wetlands are essential to preserve their ecological functions, maintain microbial diversity, and support agricultural productivity and environmental health in the region

CONCLUSION

The wetland soil understudy had abundant microbial populations. High bacterial loads were found mostly in flooded areas. It was concluded that seven bacterial species were found inhabiting the wetland soil in Itu and their load  varied with locations and soil depth .The high diversity of species  present  in the study area ensures great potential and soil resilience in the degradation process.

REFERENCES

1 Douglas ,W. A. (2009). Wetland Microsoft Encarta Encyclopedia;http://www.encyclopedia .com

2. Mamman, G. S. ,Adedotun , A. & Garba, M.R. (2023).Variation of Floral Diversity Baturiya Wetland Game Reserve  Hadejia Jigawa  State, Nigeria. International Journal of Agriculture and Nutrition  5 (1): 114 -119.

3. Ofonime ,U .M. J. & Eduok , S. I. (2018).Microbiological . Physicochemical  and enzyme profile of Ayadehe  Coastal  Wetland soils, Nigeria , Journal of scientific Research and Reports , 20(2) 1-11. 

4. Winter, D. (2013).Forest Management Evaluation and coordination .Wetland  Conservation  and Environmental Research centre http://www.erc.darvis /edu/new/currentnewsletter 

5. Bassey, M. E., Iwatt, M. U., Umana, S. I., Akan, O. D., & Akpakpan, A. E. (2026). Heavy metal resistance in microorganisms isolated from waste dumpsites in Uyo Metropolis, Nigeria. South Asian Journal of Research in Microbiology, 20(3), 42–49.

6. Chen, T. K., & Shiau, Y. J. (2025). Effects of Soil Properties and Seasonal Variations on Microbial Communities in Constructed Wetlands. Microbial ecology, 88(1), 64.

7. Zhang, L., Zhao, P., Gao, G., Ding, G., Zhang, Y., Li, Q., & Liu, Y. (2026a). Soil bacterial community assembly and driving factors in wetlands along the southern margin of the Tarim Basin. Applied Soil Ecology, 220, 106882.

8.. Huang, X., He, Z., Wang, Y., Wang, F., Zheng, Z., Zuo, Y., Cao, Y., Yao, X., She, Z., Ge, Y., & Li, Y. (2025). Assessment of soil microbial communities and diversity in typical coastal wetlands along a succession gradient: Implications for reconstructing the long-term evolution of coastal wetlands. Environmental Technology & Innovation, 39, 104263

9. Umana, S., Edet, N., Uko, M., Agbo, B., & Bassey, M. (2018). Microbiological quality of indoor and outdoor air within biological sciences laboratories in Akwa Ibom State University, Nigeria. Frontiers in Environmental Microbiology, 4(6), 124–132.

10. Ogban, P. I.,Effiong, G. S.,Obi, J. C. & Ibia  T. O. (2011). Characteristics potential and constraints  of Wetland soil for Agricultural Development  in Akwa Ibom State , South Eastern Nigeria. Nigerian Journal of Agriculture, Food and Environment 7 (2), 80 – 87. 

11. Udoh, B. T. and Edem , S. O. , Ibia, T.O., Udo , B. U.  (2008). Assessment of micro-nutrient status of inland  depression  and flood plain (wetland)  Soils in Akwa Ibom , State South Eastern Nigeria. Journal  of  Tropical Agriculture , Food , Environment and Extension ,7(2): 156-161.

12. Hadejia  Nguru  Wetland  Conservation   Nguru  Wetland  Conservation  Project (HNWCP) (1999). Problem  associated with  Wetlands  in Jigawa  State . Jigawa State Ministry of   Environment  

13. Udotong , I.R. , John ,O. U.M.& Udotong , J.I.R. (2008).Microbiological and Physicochemical studies Of Wetland Soils in Eket ,Nigeria .World Academy of Science, Engineering and Technology.  20:837- 842. 

14. Akpabio, U. D. and Akpakpan, A. E. (2012). Evaluation of Nutritive and Anti-nutritive compositions of the seeds of Monodoramyristica (African Nutmeg). World Journal of Applied Science and Technology, 4(1): 49-55.  

15. Akpabio, U. D., Wilson, L. A., Akpakpan, A. E and I. B. Obot (2012). Phytochemical Screeing and proximate composition of Cassia hirsute seeds. Elixir Journal of Applied Chemistry 8704-8707

16. Etuk, B. A., Udiong, D. S. and Akpakpan, A. E. (2020a). Human Health Risk Assessment of Trace Metals in Water from Cross River Estuary, Niger Delta, Nigeria. Asian Journal of Chemical Sciences 7(3): 1-11

17. Etuk, B. A., Akpakpan, A. E., & Udiong, D. S. (2020b). Bioaccumulation and human health risk assessment of trace metals in Tympanotonus fuscatus from Cross River Estuary, Niger Delta, Nigeria. Journal of Materials and Environmental Science, 11(7), 1079-1093

18. Jaishankar, M., Tseten, T., Anbalagan, N., Mathew, B. B., & Beeregowda, K. N. (2014). Toxicity, mechanism and health effects of some heavy metals. Interdisciplinary Toxicology, 7(2), 60–72.

19. Akpakpan, A. E.  Eduok, U. M.  Udiong, D. S.  Udo, I. E.  Ntukuyoh, A. I. (2012).Level of Metals in Kernels and Shells of Oil Palm and Coconut Fruits. International Journal of Modern Chemistry, 2(1): 20-27

20. Nsi, E. W., Uwanta, E. J., Akpakpan, A. E., & Ekwere, I. O. (2020). Analytical assessment of borehole water in some local government areas of Akwa Ibom State, South-South Nigeria. European Scientific Journal, 16(13), 122–136.

21. Anderson, J.M. and Ingram, J.S.I. (1993) Tropical Soil Biology and Fertility: A Handbook of Methods. Publication of CABI, Wallingford, UK, 2, 68-70.

22. R. Cruickshank, J. P. Duguid, B. P. Marmion and R. H. A. Swain, “Medical Microbiology,” 12th Edition, Edward Arnold Publishers, Vol. II, 1975.

23. Domsch, K.H., Gams, W. and Anderson, T.H. (1980) Compendium of Soil Fungi. Vol. 1-2, Academic Press, London.

24. Akpan , G.U. and Ayegba, S.N. (2024).A study on Physicochemical , Microbiological  and Biochemical Properties  of Wetland  Soils at Eket . African Journal of Agriculture  and Food Science. 7 (2): 64-85

25. Umana, I., Uko, P., Bassey, P., & Essien, P. (2017). Hydrocarbons degrading potential of stimulated cultures of bacteria isolated from humic fresh water sediment of Eniong River in the Niger Delta of Nigeria. Microbiology Research Journal International, 21(3), 1–13.

26. Macaulay, B. M. (2015). Understanding the behavior of oil-degrading microorganisms to enhance the microbial remediation of spilled petroleum. Applied Ecology and Environmental Research, 13(1), 247–262.

27. Ballesteros , N.,  PaezL. , Luna , N. Reina, A., Urrea V., Sanchez, C., Rammirez, J. D. & Munoz , M. (2023). Characterization of  microbial communities  in seven Wetlands with different  anthropogenic  burden  using next  Generation Sequencing in Bogota , Columbia . Scientific Reports 13,16973

28. Head, I. M. , Jones, D. M.and  Roling , W.F.M. (2006). Marine Microorganisms make a meal of oil . Natural Rev. of  Microbiol. 4 173 –  182

29 Uko, M. P., Uko, I. C., Umana, S. I., & Bassey, M. P. (2017). Microbial load, prevalence and antibiotics susceptibility of bacteria isolated from Naira notes. Asian Journal of Biotechnology and Bioresource Technology, 1(4), 1–8.

30. Umana, S., Ekpo, U., Bassey, M., Uko, M., & Abiaobo, N. (2017). Virulence factors of bacteria isolated from fish sold at open air market centre in Okepedi, Itu, Akwa Ibom State, Nigeria. Journal of Applied Life Sciences International, 14(4), 1–14.

31. Zheng, L., Tian, Q., Tan, Q., Wang, X., Xing, Y., & Zhang, Y. (2026b). Biogeography and diversity of wetland soils bacterial communities across temperature zones based on independent studies. Journal of Environmental Sciences, 160, 439–449.

32. He, D., Liu, W., Wang, L., Xu, W., Zhang, J., Lu, Q., & Luo, T. (2026). Microbial community composition and major environmental factors influencing changes in different vegetation soils of coastal wetlands. Microorganisms, 497 (14), 1-13.