Reducing the Average P Factor Value in Sloping Land Through Scenarios that Incorporate Terracing and Contour Farming Practices

Öz

The soil protection (P) factor, one of the components of the Revised Universal Soil Loss Equation (RUSLE) Model, is critical in influencing erosion. It significantly reduces soil erosion by minimizing surface runoff on sloping terrains. The P factor is unitless. In this article, 4 scenarios involving soil conservation practices tailored to the slope percentages of the study area, which features a sloping landscape, were developed. Terracing and contour farming were proposed as soil conservation strategies. Areas with slopes ranging from 6% to 12% were regarded as suitable for contour farming, while those with slopes between 12% and 30% were considered ideal for terracing practices. The study revealed that scenario 4 lowered the average P factor value of the study area from 1 to 0.58. This outcome indicated that the scenarios devised could decrease the average P factor value in the study area by 42%. It is believed that the approach employed in this study can effectively reduce the average P factor value in sloping regions facing erosion issues.

Anahtar Kelimeler

• Land use
• Mapping
• RUSLE
• Soil conservation practices
• Soil erosion

Kaynakça

1. Adhikari, B., & Nadella, K. (2011). Ecological economics of soil erosion: a review of the current state of knowledge. Annals of the New York Academy of Sciences, 1219(1), 134-152. https://doi.org/10.1111/j.1749-6632.2010.05910.x
2. Anonymous. (2025). Seasonal normals for the provinces. Retrieved April 17, 2025, from https://www.mgm.gov.tr/veridegerlendirme/il-ve-ilceler-istatistik.aspx?m=K.MARAS
3. Arnáez, J., Lana-Renault, N., Lasanta, T., Ruiz-Flaño, P., & Castroviejo, J. (2015). Effects of farming terraces on hydrological and geomorphological processes. A review. Catena, 128, 122-134. https://doi.org/10.1016/j.catena.2015.01.02
4. Artun, O., & Koca, Y. K. (2018). Determination of Soil Losses Using RUSLE Model and Geographical Information Systems (GIS) in a Selected Area in Mediterranean Region of Turkey. Fresenius Environmental Bulletin, 27(5), 3359-3366.
5. Aytop, H., & Pınar, M. Ö. (2024). Evaluation of agricultural productivity loss of vineyards through water erosion in Türkiye. Applied Fruit Science, 66(2), 667-676. https://doi.org/10.1007/s10341-024-01035-6
6. Aytop, H., & Şenol, S. (2022). The effect of different land use planning scenarios on the amount of total soil losses in the Mikail Stream Micro-Basin. Environmental Monitoring and Assessment, 194(5), 321. https://doi.org/10.1007/s10661-022-09937-2
7. Didoné, E. J., Minella, J. P. G., & Piccilli, D. G. A. (2021). How to model the effect of mechanical erosion control practices at a catchment scale? International Soil and Water Conservation Research, 9(3), 370-380. https://doi.org/10.1016/j.iswcr.2021.01.007
8. Ebabu, K., Tsunekawa, A., Haregeweyn, N., Tsubo, M., Adgo, E., Fenta, A. A., ... & Poesen, J. (2022). Global analysis of cover management and support practice factors that control soil erosion and conservation. International Soil and Water Conservation Research, 10(2), 161-176. https://doi.org/10.1016/j.iswcr.2021.12.002

9. FAO. (2016). Global soil partnership endorses guidelines on sustainable soil management. Retrieved April 05, 2025, from http://fao.org/global-soilpartnership/resources/highlights/detail/en/c/416516/
10. FAO. (2000). Manual on Integrated Soil Management and Conservation Practices. Rome, Italy: FAO.
11. FAO. (2003). Soil and Water Conservation with a Focus on Water Harvesting and Soil Moisture Retention. Nairobi, Kenya: Ministry of Agriculture and Rural Development.
12. García-Ruiz, J. M., Beguería, S., Nadal-Romero, E., González-Hidalgo, J. C., Lana-Renault, N., & Sanjuán, Y. (2015). A meta-analysis of soil erosion rates across the world. Geomorphology, 239, 160-173. https://doi.org/10.1016/j.geomorph.2015.03.008
13. Kebede, B., Tsunekawa, A., Haregeweyn, N., Adgo, E., Ebabu, K., Meshesha, D. T., ... & Fenta, A. A. (2021). Determining C-and P-factors of RUSLE for different land uses and management practices across agro-ecologies: case studies from the Upper Blue Nile basin, Ethiopia. Physical Geography, 42(2), 160-182. https://doi.org/10.1080/02723646.2020.1762831
14. La, N., Bergkvist, G., Dahlin, A. S., Mulia, R., Nguyen, V. T., & Öborn, I. (2023). Agroforestry with contour planting of grass contributes to terrace formation and conservation of soil and nutrients on sloping land. Agriculture, Ecosystems & Environment, 345, 108323. https://doi.org/10.1016/j.agee.2022.108323
15. Liu, X., Xin, L., & Lu, Y. (2021). National scale assessment of the soil erosion and conservation function of terraces in China. Ecological Indicators, 129, 107940. https://doi.org/10.1016/j.ecolind.2021.107940
16. Madenoğlu, S., Pınar, M. Ö., Şahin, S., & Erpul, G. (2024). Sustainable land management for mitigating soil erosion at the catchment scale. Turkish Journal of Agricultural Research, 11(2), 176-190. https://doi.org/10.19159/tutad.1434369
17. Panagos, P., Borrelli, P., Meusburger, K., Van Der Zanden, E. H., Poesen, J., & Alewell, C. (2015). Modelling the effect of support practices (P-factor) on the reduction of soil erosion by water at European scale. Environmental science & policy, 51, 23-34. https://doi.org/10.1016/j.envsci.2015.03.012
18. Pınar, M. Ö., & Erpul, G. (2023). Upscaling plot-based measurements of RUSLE C-factor of different leaf-angled crops in semi-arid agroecosystems. Environmental Monitoring and Assessment, 195(11), 1341. https://doi.org/10.1007/s10661-023-11970-8
19. Renard, K. G., Foster, G.A., Weesies, D.A., McCool, D.K., Yoder, D.C., (1997) Predicting soil erosion by water: a guide to conservation planning with the Revised Universal Soil Loss Equation (RUSLE). Agriculture handbook no. 703. USDA, Washington
20. Saygın, F., Aytop, H., & Dengiz, O. (2025). Developing land-use planning scenarios in Türkiye to reduce water-induced soil erosion. Environmental Conservation, 52(1), 31-40. https://doi.org/10.1017/S0376892924000298
21. Sud, A., Sajan, B., Kanga, S., Singh, S. K., Singh, S., Durin, B., ... & Chand, K. (2024). Integrating RUSLE model with cloud-based geospatial analysis: a google earth engine approach for soil erosion assessment in the Satluj watershed. Water, 16(8), 1073. https://doi.org/10.3390/w16081073
22. Tian, P., Zhu, Z., Yue, Q., He, Y., Zhang, Z., Hao, F., ... & Liu, M. (2021). Soil erosion assessment by RUSLE with improved P factor and its validation: Case study on mountainous and hilly areas of Hubei Province, China. International Soil and Water Conservation Research, 9(3), 433-444. https://doi.org/10.1016/j.iswcr.2021.04.007
23. Wischmeier, W. H., & Smith, D. D. (1978). Predicting rainfall erosion losses. USDA Agricultural Handbook, No: 537, USA.