Evaluation of soil quality in a cornell-based polye ecosystem in a Karstic Area: Integration of geostatistics and machine learning

Aktop Aktop; Sevda Altunbaş Beritanli; Bayram Çağdaş Demirel

doi:10.18393/ejss.1901800

Evaluation of soil quality in a cornell-based polye ecosystem in a Karstic Area: Integration of geostatistics and machine learning

Abstract

Assessing soil quality and establishing processes to control quality is critically important in environmentally sensitive karst systems. This study aimed to analyze the spatial behavior of soil quality and the dominant soil properties controlling it in the karstic polje system of Gembos Plain (Southern Turkey) using the Cornell Soil Quality Index (SQI). SQI values were calculated using physical and chemical data obtained from 72 soil samples (0–30 cm). According to analysis results SQI values ranged from 53 to 59, with an average value of approximately 56. Semivariogram analysis showed that SQI exhibited moderate spatial dependence; the Gaussian variogram model was selected as the most appropriate model due to lowest error values and RMSSE close to 1. The spatial distribution obtained by ordinary kriging revealed that low-to-medium quality classes were dominant across the area and that geochemical micro-scale patterns prevailed over distinct morphological zoning. In addition, Random Forest and XGBoost models showed the highest performance in machine learning analyses (R² = 0.74 and 0.71). Variable importance analysis has shown that soil reaction (pH) is the primary control factor determining SQI variability, while P, Fe, and K are effective at a secondary level. Also soil organic matter plays a secondary role in explaining SQI variability due to its narrow range of variation. The results reveal that soil quality in karstic polje conditions is controlled by chemical constraints rather than physical properties, and that the combined use of geostatistical modeling and machine learning significantly improves the interpretability of soil quality analyses.

Keywords

References

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Details

Primary Language

English

Subjects

Soil Sciences and Plant Nutrition (Other)

Journal Section

Research Article

Authors

Aktop Aktop This is me
0000-0002-6667-9701
Türkiye

Sevda Altunbaş Beritanli ^*
0000-0001-9779-9784
Türkiye

Bayram Çağdaş Demirel
0000-0001-5402-0339
Türkiye

Publication Date

April 1, 2026

Submission Date

October 21, 2025

Acceptance Date

February 23, 2026

Published in Issue

Year 2026 Volume: 15 Number: 2

DOI

https://doi.org/10.18393/ejss.1901800

IZ

https://izlik.org/JA88CE38LB

Cite

RIS / Bibtex

APA

Aktop, A., Altunbaş Beritanli, S., & Demirel, B. Ç. (2026). Evaluation of soil quality in a cornell-based polye ecosystem in a Karstic Area: Integration of geostatistics and machine learning. Eurasian Journal of Soil Science, 15(2), 291-301. https://doi.org/10.18393/ejss.1901800

AMA

1.Aktop A, Altunbaş Beritanli S, Demirel BÇ. Evaluation of soil quality in a cornell-based polye ecosystem in a Karstic Area: Integration of geostatistics and machine learning. EJSS. 2026;15(2):291-301. doi:10.18393/ejss.1901800

Chicago

Aktop, Aktop, Sevda Altunbaş Beritanli, and Bayram Çağdaş Demirel. 2026. “Evaluation of Soil Quality in a Cornell-Based Polye Ecosystem in a Karstic Area: Integration of Geostatistics and Machine Learning”. Eurasian Journal of Soil Science 15 (2): 291-301. https://doi.org/10.18393/ejss.1901800.

EndNote

Aktop A, Altunbaş Beritanli S, Demirel BÇ (April 1, 2026) Evaluation of soil quality in a cornell-based polye ecosystem in a Karstic Area: Integration of geostatistics and machine learning. Eurasian Journal of Soil Science 15 2 291–301.

IEEE

[1]A. Aktop, S. Altunbaş Beritanli, and B. Ç. Demirel, “Evaluation of soil quality in a cornell-based polye ecosystem in a Karstic Area: Integration of geostatistics and machine learning”, EJSS, vol. 15, no. 2, pp. 291–301, Apr. 2026, doi: 10.18393/ejss.1901800.

ISNAD

Aktop, Aktop - Altunbaş Beritanli, Sevda - Demirel, Bayram Çağdaş. “Evaluation of Soil Quality in a Cornell-Based Polye Ecosystem in a Karstic Area: Integration of Geostatistics and Machine Learning”. Eurasian Journal of Soil Science 15/2 (April 1, 2026): 291-301. https://doi.org/10.18393/ejss.1901800.

JAMA

1.Aktop A, Altunbaş Beritanli S, Demirel BÇ. Evaluation of soil quality in a cornell-based polye ecosystem in a Karstic Area: Integration of geostatistics and machine learning. EJSS. 2026;15:291–301.

MLA

Aktop, Aktop, et al. “Evaluation of Soil Quality in a Cornell-Based Polye Ecosystem in a Karstic Area: Integration of Geostatistics and Machine Learning”. Eurasian Journal of Soil Science, vol. 15, no. 2, Apr. 2026, pp. 291-0, doi:10.18393/ejss.1901800.

Vancouver

1.Aktop Aktop, Sevda Altunbaş Beritanli, Bayram Çağdaş Demirel. Evaluation of soil quality in a cornell-based polye ecosystem in a Karstic Area: Integration of geostatistics and machine learning. EJSS. 2026 Apr. 1;15(2):291-30. doi:10.18393/ejss.1901800