Eurasian Journal of Soil Science

Abstract

Soils in arid and semi-arid regions often have low organic matter and high calcium carbonate, limiting fertility and crop productivity. In Central Anatolia, Türkiye, these constraints challenge sustainable agriculture. Biochar and humic substances are increasingly used as soil amendments to improve soil properties and nutrient availability. This study evaluated the effects of barnyard manure, poultry manure, their derived biochars, and humic acid on dwarf bean growth and nutrient uptake in a calcareous soil from Central Anatolia under greenhouse conditions. A completely randomized design with four replications was employed. Manures and their derived biochars were applied at 0.5, 1, and 3% (w/w), whereas humic acid was applied at 150, 300, and 600 mg kg⁻¹. Plant height, fresh weight, dry weight, and macronutrrient and micronutrient uptake were measured. Amendment type and application rate significantly affected plant growth (p < 0.01). Poultry manure-derived biochar applied at 3% produced the most pronounced effects, increasing fresh weight by 233.3%, phosphorus uptake by 100%, and potassium uptake by 93.8%. Macronutrient uptake, except that of nitrogen, responded to the treatments, whereas micronutrient uptake showed more pronounced changes following both biochar and humic acid applications. Overall, manure-derived biochars generally performed as well as or better than humic acid, depending on the application rate. These results indicate that manure-derived biochar and humic acid can enhance plant growth and nutrient uptake in calcareous soils deficient in organic matter. Thus, organic amendments offer effective strategies for improving soil fertility and supporting sustainable crop production in semi-arid agroecosystems.

Keywords

Barnyard manure, biochar, dwarf bean, humic acid, poultry manure, plant nutrition

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<p>Van Zwieten, L., Kimber, S., Morris, S., Chan, K., Downie, A., Rust, J. et al., 2010. Effects of biochar from slow pyrolysis of papermill waste on agronomic performance and soil fertility. <em>Plant and Soil </em>327: 235-246. <a href="https://doi.org/10.1007/s11104-009-0050-x">https://doi.org/10.1007/s11104-009-0050-x</a></p>

<p>Woldetsadik, D., Drechsel, P., Marschner, B., Itanna, F., Gebrekidan, H., 2017. Effect of biochar derived from faecal matter on yield and nutrient content of lettuce (Lactuca sativa) in two contrasting soils. <em>Environmental Systems Research </em>6: 2. <a href="https://doi.org/10.1186/s40068-017-0082-9">https://doi.org/10.1186/s40068-017-0082-9</a></p>

<p>Yadav, N.K., Kumar, R., Bishnoi, S.K., Patel, P., 2015. Effect of different types of biochar application on secondary and micronutrients content and uptake by fodder maize. <em>International Journal of Bio-Resource and Stress Management </em>6(3): 386-395. <a href="https://doi.org/10.5958/0976-4038.2015.00049.4">https://doi.org/10.5958/0976-4038.2015.00049.4</a></p>

<p>Yoldas, F., Ceylan, S., Mordogan, N., Esetlili, B.C., 2011. Effect of organic and inorganic fertilizers on yield and mineral content of onion (Allium cepa L.). <em>African Journal of Biotechnology</em> 10: 11488-11492. <a href="https://doi.org/10.5897/AJB10.2535">https://doi.org/10.5897/AJB10.2535</a></p>

<p>Zhou, L., Monreal, C.M., Xu, S., McLaughlin, N.B., Zhang, H., Hao, G., Liu, J., 2019. Effect of bentonite-humic acid application on the improvement of soil structure and maize yield in a sandy soil of a semi-arid region. <em>Geoderma</em> 338: 269-280. <a href="https://doi.org/10.1016/j.geoderma.2018.12.014">https://doi.org/10.1016/j.geoderma.2018.12.014</a></p>

Abstract

Soils in arid and semi-arid regions often have low organic matter and high calcium carbonate, limiting fertility and crop productivity. In Central Anatolia, Türkiye, these constraints challenge sustainable agriculture. Biochar and humic substances are increasingly used as soil amendments to improve soil properties and nutrient availability.  This study evaluated the effects of barnyard manure, poultry manure, their derived biochars, and humic acid on dwarf bean growth and nutrient uptake in a calcareous soil from Central Anatolia under greenhouse conditions. A completely randomized design with four replications was employed.  Manures and their derived biochars were applied at 0.5, 1, and 3% (w/w), whereas humic acid was applied at 150, 300, and 600 mg kg⁻¹. Plant height, fresh weight, dry weight, and macronutrrient and micronutrient uptake were measured. Amendment type and application rate significantly affected plant growth (p < 0.01). Poultry manure-derived biochar applied at 3% produced the most pronounced effects, increasing fresh weight by 233.3%, phosphorus uptake by 100%, and potassium uptake by 93.8%. Macronutrient uptake, except that of nitrogen, responded to the treatments, whereas micronutrient uptake showed more pronounced changes following both biochar and humic acid applications. Overall, manure-derived biochars generally performed as well as or better than humic acid, depending on the application rate. These results indicate that manure-derived biochar and humic acid can enhance plant growth and nutrient uptake in calcareous soils deficient in organic matter. Thus, organic amendments offer effective strategies for improving soil fertility and supporting sustainable crop production in semi-arid agroecosystems.

Keywords: Barnyard manure, biochar, dwarf bean, humic acid, poultry manure, plant nutrition

Author contributions: Noyan Eken: Investigation, Data curation, Formal analysis, and Writing - original draft. Mehmet Hamurcu: Methodology, Validation, Formal analysis, and Writing - review and editing. Sait Gezgin: Conceptualization, Resources, Supervision, and Writing - review and editing. Erdogan Esref Hakki: Conceptualization, Methodology, Supervision, Project administration, and Writing - review and editing. All authors read and approved the final version of the manuscript.

Funding: This research was financially supported by the Selcuk University Scientific Research Projects Coordination Unit (BAP) under Project No. 17401066.

Data availability statement : The data supporting the findings of this study are included in the article. Additional data are available from the corresponding author upon reasonable request.

Declaration of competing interest: The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this article.

Ethics approval: Ethics approval was not required because this study did not involve human participants or animals.

Acknowledgements: This study was conducted as part of the Master of Science (MSc) thesis of Noyan Eken (YOKTEZ No. 485130).

Use of artificial intelligence: No AI tool was used for language editing or translation.

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