Integrated Analysis of Organic Carbon and Soil Fertility Indicators in Peri-Urban Agricultural Lowlands in Northern Côte d'Ivoire in a Context of Climate Change

The urban and peri-urban lowlands of northern Côte d’Ivoire are vital for ensuring local food security and meeting the growing demand for staple food production in cities such as Korhogo. However, these environments are under increasing pressure from soil degradation, characterised by a decline in organic carbon content, acidification and nutrient deficiencies. They are also impacted by climate change, including precipitation variability, droughts and rising temperatures. Despite their considerable agronomic and environmental potential, data on soil organic carbon stocks and the physicochemical properties of these areas is insufficient, which hinders the development of sustainable agricultural strategies. Conducted in December 2024, this study aimed to undertake an integrated analysis of soil organic carbon and physicochemical parameters in two representative peri-urban lowlands in the Korhogo region (Natio and Logokaha). The study sought to characterise the agronomic and ecological potential of these areas, identify major constraints affecting production systems under conditions of climatic variability, and propose ways to sustainably improve soil fertility. The methodology involved taking stratified soil samples at two depths (0–20 cm and 20–40 cm) along transects designed to capture topographical variability. Physico-chemical properties and bulk density were analysed in the laboratory, followed by statistical analysis of the measured parameters. The results indicate that the soils at both sites are predominantly silty and generally low in fertility, particularly with regard to organic carbon, total nitrogen, available phosphorus and exchangeable bases. There was a particular deficiency of phosphorus, and elevated sodium concentrations pose a risk of sodification. The organic carbon stock was found to be higher at Logokaha. This spatial variability highlights the need for management practices that are tailored to specific topographical units. In order to preserve and enhance soil fertility, an integrated management approach combining regular organic amendments, liming materials, judicious phosphorus fertilisation and optimised water management is recommended, thereby strengthening soil resilience in the face of climate change.