Global Patterns of Soil Fertility, Leaf Nutrient Status, and Yield Drivers in Coffee Agroecosystems

Abstract Coffee productivity varies widely among regions and production systems, and the contributions of soil fertility, plant nutrient status, and fertilization to this variation remain poorly resolved. This study aimed to (1) characterize global variability in soil fertility and leaf nutrient concentrations, (2) evaluate relationships among soil properties, fertilization practices, leaf nutrient concentrations, and yield, (3) examine nutrient clustering and regional soil-order patterns, and (4) identify yield-associated leaf nutrient concentrations. We synthesized 1,925 observations from 184 peer-reviewed studies. Linear regression, partial least squares regression, and principal component analysis were used to evaluate relationships among soil properties, leaf nutrients, and fertilizer inputs. Prediction profiling was applied to estimate nutrient concentrations associated with higher yield. Soil properties varied widely across regions and soil orders, whereas leaf nutrient concentrations showed narrower ranges. Soil-leaf relationships were strong for N, Ca, Mg, Mn, and Zn, and weaker for P and K. Fertilization generally increased corresponding leaf nutrient concentrations, though effects on soil nutrients were inconsistent. Yield was positively associated with N and K fertilization, planting density, reduced soil acidity, and elevated soil micronutrients. Soil and management variables explained ~ 56% of global yield variation despite substantial heterogeneity among studies. Leaf nutrient concentrations provide a useful indicator of plant nutritional status, but yield is more strongly influenced by soil properties and management practices. Results suggest that coffee yield may be associated with higher N and Mn and lower K concentrations than currently emphasized in many published sufficiency ranges, highlighting the need for regionally adapted nutrient management strategies.