International Journal of Life Science and Agriculture Research

This study was conducted in the Al-Kawtha Agricultural Project, Babil Governorate, Iraq (874 km²), with the aim of evaluating the spatial distribution of major soil nutrients. Four land-use types were considered: wheat, maize, eggplant, and uncultivated land. Soil samples were collected from two depths (0–30 cm and 30–60 cm) and analyzed to determine nitrogen, phosphorus, potassium, iron, and zinc.as well as key physical and chemical properties.The results showed substantial variation in nutrient levels among the different land uses, while soil pH remained relatively stable. Nitrogen concentrations ranged from 18.90 to 38.9 mg kg⁻¹, phosphorus from 4.30 to 11.27 mg kg⁻¹, potassium from 97.60 to 145.3 mg kg⁻¹, iron from 3.58 to 7.58 mg kg⁻¹, and zinc from 0.31 to 0.46 mg kg⁻¹. The highest nutrient concentrations were observed in uncultivated areas, reflecting minimal nutrient removal, whereas cultivated fields—especially maize—showed lower nitrogen and organic matter content. Phosphorus was more abundant in deeper layers, while other nutrients were concentrated in the topsoil .Statistical analysis (p ≤ 0.05) confirmed that Findings revealed that soil nutrient distribution was significantly influenced by both land-use type and soil depth. These findings emphasize the long-term impact of cultivation on soil nutrient depletion and highlight the necessity of sustainable management strategies, including organic fertilization and crop rotation, to preserve soil fertility and productivity.

Soil fertility, Spatial variability, Geostatistics, Land use

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