The relationship between soil biomass and soil quality index for Kafr El-Dawar region, Beheira Governorate

Abstract

The current investigation was conducted in the Kafr El-Dawar region to study the relationship between soil microbial biomass and soil quality index. Thirty-nine soil samples were taken for the chemical characteristics used to determine the soil quality index by the Soil Management Assessment Framework (SMAF) procedures. Pearson correlation relationship and Principal components analysis (PCA) between soil quality index and soil parameters were done as well as regression between soil quality index and microbial biomass. For the soil microbial biomass, the lowest value was about 186 mg kg-1 (5% of the total samples). The highest value was about 387 mg kg-1 (5% of the total samples). The average microbial biomass of the samples was about 299 mg kg 1. Approximately 50% of the total samples have a value equal to the average sample value. Higher significant correlation was observed among soil pH with CaCO3 content. Significant correlation was observed among soil pH with Fe and Mn. Soil quality index had a higher significant correlation with Ca, Mg, N, K, Cu, and Zn. P was a more effective factor on soil quality index. The chemical properties had the most impact on the soil quality index. All samples have a soil quality index score of less than 50%. About 69.2% were poor quality (SQI less than 40%), and the rest were moderate quality (SQI between 40 and 60%). Microbial biomass is a key soil characteristic that influences soil quality according to the regression result. Further research should include biological and other physicochemical soil properties to enlarge soil quality index.