Influence of Repeated Agrochemical Inputs on Nutrient Availability and Heavy Metal Status of Lowland Soils of Ifite-Ogwari Anambra State Nigeria
Keywords:
Lowlands, Soils, Fertility, Agrochemicals, Heavy metalsAbstract
This study evaluated the influence of repeated agrochemical inputs on nutrient availability and heavy metal status of lowland soils in Ifite-Ogwari, Anambra State. Composite soil samples were collected from agrochemical-treated fields (AGI) and adjacent fallow soils (control) at two depths (0–15 cm and 15–30 cm). Standard laboratory analyses were conducted to determine texture, bulk density, pH, organic carbon (OC), total nitrogen (TN), exchangeable bases, effective cation exchange capacity (ECEC), available phosphorus (Av.P), and concentrations of arsenic (As) and lead (Pb). Results showed significant reductions (p ≤ 0.05) in OC, TN, Ca²⁺, and Av.P under AGI soils compared with controls, indicating fertility depletion. Soil pH remained acidic across sites, but AGI soils recorded slightly higher values. Heavy metals exhibited contrasting trends; arsenic (As) was significantly higher in AGI soils at 15 – 30 cm depth, while Pb concentrations showed no significant difference (p ≤ 0.05) between AGI and control soils nor across depths. Correlation analysis revealed that arsenic (As) was strongly correlated with soil texture (silt, clay) and pH, whereas Pb correlated with exchangeable bases (Na⁺, Mg²⁺, Ca²⁺). Although As and Pb levels remained below international safety limits, the observed build-up under continuous inputs highlights the risk of long-term accumulation. The findings demonstrate that repeated agrochemical use compromises soil fertility and promotes gradual heavy metal enrichment, underscoring the need for integrated soil fertility management and reduced dependence on chemical inputs in lowland rice systems.
References
1) Cheraghi, M., Shahbazi, K., Marzi, M., Yeganeh, M., Hasheminasab, K. S., Fathi-Gerdelidani, A., Rezaei, M., and Bazargan, K. (2025). Ecotoxicology and Environmental Safety, 302: 118667. https://doi.org/10.1016/j.ecoenv.2025.118667
2) Elumalai, P., Gao, X., Parthipan, P., Luo, J., and Cui, J. (2025). Agrochemical pollution: A serious threat to environmental health. Current opinion in Environmental Science & Health, 43: 100597. https://doi.org/10.1016/j.coesh.2025.100597
3) Feszterova, M., Kowalska, M., and Hudec, M. (2024). Assessing the impact of soil humic substances, textural fractions on the sorption of heavy metals (Cd, Pb). Applied Sciences, 14(7): 2806. https://doi.org/10.3390/app14072806
4) Goud, B. R., Raghavendra, M., Prasad, P.N. S., Hatti, V., Halli, H. M., Nayaka, V. G. V., Suresh, G., Maheshawari, K. S., Adilakshmi, G., Reddy, G. P., and Rajpoot, S. K. (2022). Sustainable management and restoration of fertility of damaged soils. Agriculture Issues and Policies. Ecosystem Services, 113 – 131.
5) Guan, X., Cao, W., Liu, D., Zhao, H., Lu, M., Gao, X., Chen, X., Liu, Y., and Tian, S. (2025). Reducing cation leaching and improving greenhouse cucumber’s nutritional yield through optimized organic-inorganic fertilization. Agronomy, 15(7): 1523. https://doi.org/10.3390/agronomy15071523
6) Kicinska, A., Pomykala, R., and Izquierdo-Diaz, M. (2021). Changes in soil pH and mobility of heavy metals in contaminated soils. European Journal of Soil Science, 73(1): e13203. https://doi.org/10.1111/ejss.13203
7) Kumar, A., Kumar, V., Thakur, M., Singh, K., Jasrotia, R., Kumar, R., and Radziemska, M. (2025). Global Perspectives on Lead contamination and health risks in surface water, rice grains, and soils. Land Degradation & Development, 36(7): 2159 – 2169. https://doi.org/10.1002/ldr.5510
8) Lopez-Vincent, M., Calvo-Seas, E., Alvarez, S., and Cerda, A. (2020). Effectiveness of cover crops to reduce loss of soil organic matter in a rainfed vineyard. Land, 9(7): 230. https://doi.org/10.3390/land9070230
9) Mlangeni, A. T., Chinthenga, E., Kapito, N. J., Namaumbo, S., Feldmann, J., and Raab, A. (2023). Safety of African grown rice: Comparative review of As, Cd, and Pb contamination in African rice and paddy fields. Heliyon. 9(7): e18314. https://doi.org/10.1016/j.heliyon.2023.e18314.
10) Okafor, M. J., Nweke, I. A., & Nsoanya, L. N. (2025). Comparative assessment of soil fertility and function across depths in rice-cultivated and fallow wetlands of Ifite-Ogwari and Omor in Southeastern Nigeria. International Journal of Horticulture and Agricultural Research. 1(1): 1-12. https://ijharjournal.com/index.php/ijhar/article/view/3
11) Okafor, M. J., Nweke, I. A., & Nsoanya, L. N. (2025). Soil degradation and nutrient dynamics in soils under continuous rice production in seasonal wetland ecosystems of Anambra State, Nigeria. FUDMA Journal of Sciences, 9(5): 164 – 170. www.fjsadmin.fudutsinma.edu.ng/index.php/fjs/article/view/3482/2464
12) Reda, G., Breure, M. S., Wall, D. P., Reda, A. G., and Creamer, R. E. (2025). Determination of phosphorus pools, sorption capacity and supply potential of agricultural soils of Tigray, Northern Ethopia. Geoderma Regional, 41: e00970. https://doi.org/10.1016/j.geodrs.2025.e00970
13) Reddy, K. R., Clark, M. W., and DeLaune, M.K (2013). Physicochemical characterization of wetland soils. Methods in Biogeochemistry of Wetlands, 10: 2136. https://doi.org/10.2136/sssabookser10.c3
14) Sabina, R., Paul, J., Sharma, S., and Hussain, N. (2025). Synthetic Nitrogen Fertilizer Pollution: Global Concerns and Sustainable Mitigating Approaches. In: Hussain, N., Hung, CY., Wang, L. (eds) Agricultural Nutrient Pollution and Climate Change. Springer, Cham. https://doi.org/10.1007/978-3-031-80912-5_3
15) Somolander, N., Fuchs, B., Helander, M., Puigbo, P., Tamminen, M., Saikkonen, K., and Mathew, S. A. (2025). Gyphosate and phosphate treatments in soil differentially affect crop microbiomes depending on species, tissue and growth stage. Scientific Report, 15(1): 25502. https://doi.org/10.1038/s41598-025-11430-y
16) Srivastava, S., Shukla, A., Rajput, V. D., Kumar, K., Minkina, T., Mandzhieva, S., Shmaraeva, A., and Suprasanna, P. (2021). Arsenic remediation through sustainable phytoremediation approaches. Minerals, 11(9): 936. https://doi.org/10.3390/min11090936
17) Suda, A., Baba, K., Sakurai, G., Furuya, M., and Yamaguchi, N. (2023) Enhanced dissolution of arsenic in anaerobic soils upon organic amendment application: acid detergent-soluble organic matter as a potential indicator. Sci Rep 13, 217 https://doi.org/10.1038/s41598-022-27325-1
18) Tadesse, K. A., Lu, Z., Shen, S., Daba, N. A., Li, J., Alam, M. A., Lisheng, L., Gilbert, N., Legesse, T. G., and Huimin, Z. (2024). Impact of long=term chemical nitrogen fertilization on soil quality, crop yield, and greenhouse gas emissions: with insights into post-lime application responses. Science of the Total Environmnet, 944: 173827. https://doi.org/10.1016/j.scitotenv.2024.173827
19) Wang, Z., Hasi, E., Han, X., Qingda, M. (2024). Fractal characterization of soil particle size distribution under different land use patterns on the north slope of Wula Mountain in China. J Soils Sediments 24, 1148–1164. https://doi.org/10.1007/s11368-024-03722-z
20) Yasir, M., Hossain, A., and Pratap-Singh, A. (2025). Pesticide degradation: Impacts on soil fertility and nutrient cycling. Environment, 12(8): 272. https://doi.org/10.3390/environments12080272
21) Zhang, Q., Liu, H., Mei, X., and Li, X. (2025). Topography-driven variability in atmospheric deposition and soil distribution of cadmium, lead and zinc in a mountainous agricultural area. Sci Rep 15, 20894. https://doi.org/10.1038/s41598-025-05258-9
Downloads
Published
Issue
Section
License
Copyright (c) 2025 Okafor, M. J., Odoh, P. A., Nnabuihe, E. C., Oluropo, A. A., Onunwa, A. O., Anene, C. K., Ernest, C. I., Nwaiwu, C. J., Nwankwo, J. E., Obidiebube, E. A., Uko, I. (Author); Anara, S. E. (Translator)
This work is licensed under a Creative Commons Attribution 4.0 International License.
