Selected chemical properties of soil in the traditional irrigation schemes of the Mbulu district, Tanzania

Abstract

A survey of chemical soil properties was conducted on six selected irrigation schemes of the Mbulu district, 
northern Tanzania. The focus of the study was to establish the status of the main mineral elements important for 
plant growth and crop production. Soil samples were collected from different sites and were analysed for physical 
chemical characteristics leading to the assessment of the soil fertility status by means of these main elements. The 
results showed variations in fertility status in the selected sites. Based on guidelines of soil mineral elements 
contents established elsewhere, the results showed that soil pH and excessive sodium in the soil followed by 
calcium in all sites; soil organic matter in 73% and cation exchange capacity in 50% of the sites are the major soil 
fertility constraints to crop production in the area. Crop production was also constrained by nitrogen in 50% and 
phosphorous in 46% of the sites. The information from our study could be used in designing fertiliser studies to 
establish nutrient requirements for different crops grown in these areas.