Agricultural soil health-crop nutrition-human health continuum: Soil processes, nutritional quality and sustainable management

Agricultural soil degradation threatens not only crop productivity but also the nutritional quality and safety of food. Soil physical, chemical and biological processes regulate the nutrient availability, plant nutrient acquisition, contaminant mobility and synthesis of nutritionally important compounds, thus providing an important link between soil condition and crop nutritional quality. This review examines the continuum connecting the agricultural soil health, crop nutrient density, food safety, nutritional security and human health, with particular emphasis on the mechanisms through which soil properties and management practices influence these outcomes. The evidence indicates that soil organic matter, pH, nutrient availability, water relations, microbial activity and soil-plant-microbe interactions collectively regulate crop acquisition of macro and micronutrients. These effects are generally more evident for micronutrients and phytochemicals than for macronutrients, although responses vary with crop genotype, soil type, climate and management conditions. Organic amendments, diversified cropping systems, reduced soil disturbance, integrated nutrient management and beneficial microbial associations can improve soil functioning and, under suitable conditions, enhance the nutritional quality of crops. However, the evidence does not support a simple distinction between organic and conventional production systems, because individual management practices and their interactions with environmental and crop-specific factors strongly influence outcomes. Soil contamination presents an additional food safety pathway through the transfer of potentially toxic elements and agricultural chemical residues into crops. Although links between the soil properties and crop nutrient composition are increasingly supported, evidence directly connecting soil health interventions with dietary intake and measurable human health outcomes remains comparatively limited. Future research should therefore integrate soil indicators, crop nutritional profiles, dietary exposure and health related measurements through long-term, multi-site and interdisciplinary approaches. A stronger soil crop nutrition framework can help identify the management strategies that simultaneously support soil functioning, nutritional quality, food safety and sustainable agricultural production.