A socioeconomic study is an analytical approach that aims to examine the social and economic dimensions of a system in tandem in order to understand the behaviors of actors and the factors influencing their decisions [1][2]. In particular, it makes it possible to assess the interactions between agricultural practices, producers’ living conditions, and the use of natural resources. On a global scale, rapid population growth poses a major challenge to food security. According to the United Nations, the world’s population has exceeded 8 billion and is projected to reach nearly 9.7 billion by 2050, which will lead to a significant increase in food demand [3]. For the FAO, agricultural production will need to increase by approximately 70% to meet future food needs [4]. In sub-Saharan Africa, nutritional deficits vary widely, but strong demographic pressure calls for a new approach involving better fertilizer management to improve soil health and ensure sustainable agricultural production [5]. Chad is an example of one of the world’s least productive countries where agriculture is an essential pillar of the economy, despite vulnerable production systems. Agriculture in Chad employs more than 70% of the working population and contributes significantly to the gross domestic product [6]. However, this sector faces numerous constraints, including climate variability, declining soil fertility, erratic rainfall, and land-use conflicts [7]. Agricultural production in Chad remains heavily dependent on climatic variability and the inherent, often limited, capacity of the soils. Previous studies conducted in Chad and other regions of Africa have shown that agricultural soils are generally deficient in essential nutrients, particularly nitrogen (N), phosphorus (P) and organic matter [8]-[10]. Furthermore, soils in the Sudanese zones are often characterized by sandy to sandy-loamy textures, which limit their capacity to retain water and nutrients [6]. This situation is associated with constraints on agricultural production, particularly for maize cultivation, the region’s primary food crop [11]. In response to declining soil fertility, the use of chemical fertilizers has become widespread in an effort to improve yields. These chemical inputs provide a rapid supply of soluble major nutrients such as nitrogen, phosphorus, and potassium (K) [12]. However, access to these fertilizers remains limited for many farmers due to their high cost, particularly in developing countries [13]. Furthermore, inadequate market access to inputs in rural areas poses an additional barrier to their adoption [14]. Recent studies have shown that the exclusive use of chemical fertilizers, without the addition of organic matter, can lead to progressive soil degradation, including a decrease in organic carbon, acidification, pollution and disruption of biological activities [10][15]. This situation underscores the need to adopt integrated soil fertility management approaches that incorporate sources of organic matter, judicious application of mineral nutrients, and beneficial organisms activities. According to data from the Foreign Agricultural Service [16] available in Crop Explorer, for the 2024/2025 crop year, the area planted with corn in Chad was estimated at 330,000 ha, with a production of 394,000 metric tons and an average yield of 1.19 metric tons per ha. For the 2025/2026 crop year, the harvested area remained estimated at 330,000 ha, while production was estimated at 380,000 metric tons, with an average yield of 1.15 metric tons per ha indicating a slight decrease in the corn yield. Consequently, integrated soil fertility management (ISFM) appears to be a relevant strategy, combining an adequate use of mineral fertilizers, organic amendments, and beneficial microorganisms [8][17]. Among these beneficial microorganisms, arbuscular mycorrhizal fungi (AMF) play a major role in improving the uptake of water and nutrients (particularly phosphorus) and in enhancing crop resilience to biotic and abiotic stresses [18]. Despite the importance of these issues, few studies have taken an integrated approach to the socioeconomic aspects related to the use of chemical fertilizers and the physicochemical characteristics of soils in Chad, particularly in the city of Pala. This gap limits the overall understanding of the interactions between agricultural practices, economic constraints, and soil fertility. The objectives of this study are: (i) to characterize the socioeconomic aspects of maize production systems by farmers in the city of Pala; (ii) to obtain data on the use of chemical fertilizers and the barriers to their adoption; and (iii) to assess the physicochemical characteristics of soils at three representative sites of Pala. For maize production optimization, it is essential to understand nutrient requirements based on soil characteristics [14][19]. For example, for sandy-loam soils, the application of complete NPK fertilizers (250 kg/ha) which can be broken down into 100 - 150 kg N/ha (in 2 or 3 applications), 40 - 60 kg P₂O₅, and 50 - 100 kg K₂O is essential [20]. Soil nutrient management is particularly important in the context of Chad, where improving agricultural productivity is a major challenge for food security and poverty reduction.

The results of this study highlight the high level of involvement of men (81%) in maize cultivation in the city of Pala, while women (19%) tend to focus more on vegetable farming. This distribution is consistent with observations made in sub-Saharan Africa, where climatic vulnerability, limited access to productive resources such as land, irrigation, nutrients inputs, and credit remains structurally unequal by gender, thereby influencing agricultural production systems. Targeted policies to include women in the cereal production chain could significantly improve overall productivity [1]. The predominance of the 30 - 40 age group (72%) indicates a relatively young and active agricultural population. This finding is an asset for the adoption of agricultural innovations, as demonstrated by several studies that highlight how being of working age promotes the adoption of new agricultural practices, provided there is adequate access to information and training [30]. Nevertheless, the low educational level of the majority of producers (62% with only a primary education or no education at all) constitutes a persistent barrier to the adoption of innovative techniques. The results of the socioeconomic survey show that the cost of fertilizers (74% of cases) and supply difficulties are the main obstacles to rational fertilization. Dependence on local markets, where prices are often unsubsidized, partly explains the difficulties smallholders face in accessing these resources since NPK fertilizers cost is 22,500 to 25,000 CFA F and urea 15,000 to 20,000 CFA F per 50 kg bag in Chad. Targeted public policies such as input subsidies, the development of supply cooperatives, and agricultural extension services are essential to improve small producers’ access to fertilizers and sustainable alternatives in the city of Pala [14]. Since this study did not measure yields, it does not allow for establishing a direct link between fertilizer application methods and yield levels. From a pedological perspective, the soils studied are predominantly sandy to sandy-loamy in texture, which confirms observations regarding soils in the Sudanese zones of Chad [6]. The soils of West Mayo-Kebbi exhibit textural variability that results in low water-holding capacity, low nutrient availability, and thus low natural fertility, as well as generally low crop yields [9]. The low nitrogen content observed, particularly in Dapambaye (0.026%), indicates a level that is insufficient for high crop production. The total phosphorus contents measured in the studied soils are very low (60 - 66 ppm). This low total phosphorus content, combined with the soils’ physicochemical characteristics, may contribute to limiting phosphorus availability to crops. However, low phosphorus availability is one of the major constraints on agricultural production in the Sudano-Sahelian zones [17]. The cross-sectional data from this study therefore do not allow these differences to be attributed to any specific agricultural practice. The slightly acidic pH values (6.06 to 6.53) are generally favorable for the availability of the major nutrients required by maize. The higher organic matter contents in Goïgamla (3.28%) indicate its key role in soil fertility by improving soil structure, water retention, and nutrient availability. Maintaining soil organic matter should therefore be a priority in fertility management strategies for example by improved fallow. The high variability in potassium between Herdé (38 ppm) and Goïgamla (1472 ppm) is particularly notable and warrants further investigation. However, the variations observed in potassium, calcium, and magnesium content reflects heterogeneity in soil chemical fertility, which requires a site-specific fertilization approach. The cation exchange capacity (CEC), ranging from 10.30 to 13.36 meq/100 g, indicates that sandy-loam soils have an average ability to retain nutrients supplied by mineral fertilizers. The leaching phenomenon generally observed in sandy soils partly explains farmers’ heavy reliance on chemical fertilizers and the low efficiency of fertilizer applications when they are not split into multiple applications. Furthermore, a comparison between chemical fertilizer-based fertilization systems and the application of organic matter indicates better soil health, higher levels of nutrients (C, N, P), greater microbial activity, and higher yields [31]. However, since this study is cross-sectional and based on a composite sample per site, it does not allow for the establishment of a causal relationship between the use of mineral fertilizers and soil degradation. The judicious combination of minimal inorganic, selected organic matter inputs, and beneficial microbial sources may nevertheless constitute an alternative for the biological management of sandy soil fertility [5][8]. The results show that the use of chemical fertilizers plays a significant role in the fertilization practices of the surveyed maize farmers, but need improvement by agro-ecological alternatives. Central Africa potential yield for maize is 5 - 6 t/ha under optimal management such as rainfed and irrigation; comparing Central Africa and Chad maize yield on-farm is 1.5 - 2.6t/ha. [32]. Some experimental studies conducted in the same area lead to consistent observations from results obtained in smallholder settings in the Pala area by Goalbaye et al. [33] who reported high yields of 3.10 t/ha (2009TZEE-W-STR maize and 2009TZE-DT-STR maize varieties), compared with low yields of 1.48 t/ha (CMS8704 maize variety) and 2.04 t/ha (local maize variety control). When comparing Salamat (better rainfall: 3.1 t/ha) with Mayo Kebbi Ouest (lower inputs: 2.3 t/ha) regions, there is a potential of improvement [34]. Compound cereal fertilizer (N, P, K; 15-15-15) is applied as a base fertilizer at a rate equivalent to 150 kg/ha. Topdressing fertilizer, urea, is applied in two splits at the maize 10-leaf stage and at flowering, at equivalent amounts of 50 kg/ha and 30 kg/ha, respectively. No phytosanitary treatments are applied. These differences show that corn performance can be influenced by both genetic material and environmental factors such as nutrients availability and farmers cultural practices. In this context, the adoption of Integrated Soil Fertility Management (ISFM) strategies appears essential. [17] recently demonstrated that the combination of reduced mineral fertilizers and specific organic amendments can sustainably improve soil fertility and maize yields under African conditions. According to Agricultural land potential of soils from Chad is low and average nutrient depletion in Chad is more than 30 - 60 kg NPK/ha with only 180 - 269 length in growing period. African soils (except forest zones) are inherently poor in soil organic carbon, and sandy soils are low in clay content, very low in cation exchange capacity, and annual losses are high, can reach 4.7% [35]. These authors recommend the use of inorganic fertilizers and recycling organic amendments improving nutrient use efficiency and integrated fodder to livestock, but micro dosing is also considered as pathway to Africa’s green revolution [36][37]. Managing tropical sandy soils requires boosting organic matter and soil organisms to overcome poor nutrient and water retention. Examples of increasing organic matter such as green manures and crop residues; stimulating biological activities (beneficial micro-organisms, soil fauna), plant cover crops, use biochar and crop-livestock integration. The combined use of integrated management of organic matter, inorganic fertilizers, biofertilizers such as arbuscular mycorrhizal fungi (AMF), have proved a promising approach for sustained crop production, by improving nutrient uptake, crop resilience to water and nutritional stress under climatic constraints [8][18][38][39].

This study described the socioeconomic characteristics of maize farmers and the physicochemical parameters of soil fertility in the city of Pala, West Mayo-Kebbi Province, Chad. The results show significant male involvement in maize production and a predominantly young farming population, representing significant potential for the adoption of new agricultural technologies. In terms of soil characteristics, the soils studied are predominantly sandy to sandy-loamy, with a slightly acidic pH and low water and nutrient retention capacity. They have low nitrogen and phosphorus contents and highly variable potassium levels. Organic matter content is moderate in Dapambaye, high in Herdé, and very high in Goïgamla. Farmers report using chemical fertilizers primarily NPK 20-10-10 and urea to support maize production, but their use remains limited by high costs and availability. Since no yields were measured and no long-term monitoring of soil fertility was conducted, this study cannot demonstrate an effect of fertilizers on yield nor establish that the exclusive use of mineral fertilizers has caused progressive soil degradation. In light of these observations, we believe it is necessary to adopt more sustainable agricultural practices based on Integrated Soil Fertility Management (ISFM). The judicious use of mineral fertilizers, such as micro dosing and biochar application, organic amendments, and biostimulants such as arbuscular mycorrhizal fungi (AMF) represents a promising alternative for improving maize productivity while preserving soil quality in the Sudano-Sahelian regions of Chad. AMF possess numerous beneficial properties for mitigating the major constraints observed in these sandy soils: stimulation of beneficial functions such as the uptake of water and poorly mobile nutrients, and improved tolerance to biotic and abiotic stresses. Supporting policies (subsidies, training, extension services) are essential to make these agroecological practices accessible to smallholder farmers.

Conceptualization, Izaba Aimée and Nwaga Dieudonné; methodology, Izaba Aimée; software, Mbassi Manga Gilbert; validation, Nwaga Dieudonné, Nguinambaye Mberdoum Memti, and Fokom Raymond; formal analysis, Nwaga Dieudonné; investigation, Izaba Aimée; resources, Izaba Aimée; data curation, Izaba Aimée and Mbassi Manga Gilbert; writing original draft preparation, Izaba Aimée; writing review and editing, Izaba Aimée and Nwaga Dieudonné; visualization, Nkameni Djeuga Thierry; supervision, Nguinambaye Mberdoum Memti; project administration, Izaba Aimée and Nwaga Dieudonné; funding acquisition, Izaba Aimée; translation into English, Nkameni Djeuga Thierry. All authors have read and agreed to the published version of the manuscript.