Evaluation Of Agricultural Soil Fertility And Quality In The Semi-Arid Region Of Zaër (Morocco)

Abstract

The principal objective of this study is to assess the fertility levels of agricultural soils in the semi-arid region of Zaër. To this end, thirteen soil samples were taken during a sampling campaign carried out in autumn 2021 in the first superficial layers (0-20 cm) and at depth (20-40 cm). To determine the state of fertility, physico-chemical analyses were carried out for each site, namely particle size, total limestone, pH, organic matter, electrical conductivity, exchangeable potassium, assimilable phosphorus, cation exchange capacity and exchangeable bases.

The soil results indicate that the soils in the study area are moderately acidic to moderately basic, with a pH between 5.8 and 7.9. The electrical conductivity measured in the sampled soils indicates that the soils studied remain within the limits of non-saline soils (EC < 0.6 mS/cm). Total limestone levels are below 3%, indicating that the soils studied are poor in limestone. The soils studied are relatively poor in organic matter, preventing active microbial life. However, exchangeable calcium and magnesium concentrations were found to be low, as were sodium levels. Furthermore, cation exchange capacity is high in autumn, reflecting the soil's high and low nutrient retention capacity. The available phosphorus levels analyzed show that the soils studied are reduced and that the response of phosphorus fertilizer application in these soils is likely, as the phosphorus content determined is less than 40 ppm. Exchangeable potassium levels are low and insufficient, mainly due to the intensification of cultivation in these soils in the Zaër region and the lack of control over mineral fertilization. Our study shows that the soils studied have a silty-sandy-clay texture, are mostly low in limestone and poor to moderately poor in organic matter.