قارن الطرق

	سعة التبادل الكاتيوني	رسم خرائط التربة الرقمية
المجال	علم المحاصيل	علم المحاصيل
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1920-1982	Late 1990s – early 2000s (formalised ~2003)
صاحب الطريقة	Georg Wiegner, Heinrich Rotter, Melvin E. Sumner	Multiple contributors; foundational framework by Alex McBratney and colleagues
النوع	Analytical soil characterization method	Spatial prediction and mapping pipeline
المصدر التأسيسي	Thomas, G. W. (1982). Exchangeable cations. In A. L. Page, R. H. Miller, & D. R. Keeney (Eds.), Methods of soil analysis. Part 2: Chemical and microbiological properties (2nd ed., pp. 159-165). American Society of Agronomy.	McBratney, A. B., Mendonca Santos, M. L., & Minasny, B. (2003). On digital soil mapping. Geoderma, 117(1–2), 3–52.
الأسماء البديلة	CEC, Soil nutrient retention, Base saturation	DSM, predictive soil mapping, quantitative soil-landscape modelling, geostatistical soil mapping
ذات صلة	3	1
الملخص	Cation exchange capacity (CEC) is a fundamental soil property that measures the soil's ability to hold and release positively charged nutrient ions (cations: K⁺, Ca²⁺, Mg²⁺, Na⁺, H⁺, Al³⁺) in forms available to plant roots. CEC reflects the amount and type of clay minerals and organic matter in the soil—compounds with negatively charged surface sites that attract and temporarily bind cations. High CEC soils retain nutrients longer and require less frequent fertilization; low CEC soils lose nutrients rapidly through leaching.	Digital Soil Mapping (DSM) is a quantitative, data-driven pipeline that predicts the spatial distribution of soil properties and classes across a landscape by statistically linking field observations to environmental covariates — terrain attributes, remote sensing imagery, climate surfaces, and geology layers. The approach replaces or augments traditional expert-drawn soil surveys with reproducible, spatially explicit models, and is applied in agronomy, land management, food security, and environmental assessment.