摘要：The present study investigated the land type based seasonal status of agricultural topsoil chemical properties at Bagerhat district, Bangladesh. Because of relief and seasonal effect we hypothesized the changes of soil nutrient and chemical properties in topsoil. Composite soil samples were collected from fifteen purposive sampling points in pre-monsoon and post-monsoon period of 2016-2017. Soil digestion and analysis were performed following standard procedures. Topsoil pH was strongly alkaline to slightly alkaline (8.02-7.85) in pre-monsoon and post-monsoon with a significant variation. Seasonal OM status was below the optimum level (<3.4). Mean salinity status was very slightly saline in both seasons. Total nitrogen status was low in different lands in both seasons. Phosphorus status was very low (<0.06µg/g) in post-monsoon for upland and wetland crops. Sulfur status was very high (>45.0µg/g) in both seasons for upland and wetland crops. Seasonal mean status of B, Ca and Mg was very high in different lands. Status of Zinc was medium in both seasons having a deficiency (<9.0 µg/g) in some lands. Multivariate analysis showed that lowlands were rich in salinity, OM, K, Ca, total nitrogen and S comparing with medium lowland and medium highland (LL>MLL>MHL). Considering the above issues present study suggests to avoiding excessive use of chemical fertilizer and encourages organic fertilizer for sustainable management of these agricultural lands.
