Assessment of soil salinity in the accreted and non-accreted land and its implication on the agricultural aspects of the Noakhali coastal region, Bangladesh

Abstract

Soil salinity is a global problem that has adverse effects on both agriculture and aquaculture production. The main objectives of this study were to observe the distribution pattern of soil salinity in the accreted and non-accreted land of the Noakhali district and to determine the intensity of salinity at different depths (1–2 cm, 15–20 cm, and 45–60 cm). Soil samples from 60 sampling sites were analyzed to measure electrical conductivity (EC). The two-way factorial ANOVA model revealed a significant effect of depth (p < 0.001) and sampling locations (p < 0.001) on soil salinity. After decomposition of this model, one-way ANOVA showed that 45–60 cm of depth contains significantly higher soil salinity (p < 0.01) ranging from 0.28 to 4.70 dS/m compared to 1–2 cm (ranging from 0.14 to 2.39 dS/m) and 15–20 cm (ranging from 0.18 to 2.37 dS/m) depth. In the case of accreted lands, surface (1–2 cm) and mid-layer (15–20 cm) soils were found slight to severely saline, while soil at a depth of 45–60 cm was found high to extremely saline. In all cases, salinity increases from the north to southwards and surface to downwards. Our results showed that the accreted land of the Noakhali district contains higher soil salinity compared to the non-accreted land, and soil salinity is positively correlated with depth. Assessment of suitable species and pattern of traditional cropping practices in the study area show conformity with our salinity profile. The study will help stakeholders associated with agricultural development and management in planning and designing the future land use and cropping practices.

Keywords

• Earth sciences
• Soil salinity
• Electrical conductivity
• Accreted land
• Meghna river estuary