A new index to assess soil sustainability based on temporal changes of soil measurements using geomatics – an example from El-Sharkia, Egypt

Abstract

A Soil Sustainability Index (SSI) is developed based on integration of Soil Degradation Rate (SDR), Soil Fertility Index (SFI), Soil Quality Index (SQI) and Soil Resilience Rate (SRR). SDI, SRR, SQI, and SFI resemble in being measurable from soil attributes that reveal the soil-environment functionality. This approach index was calculated based on four vertices, which are represented by the SDR and SRR exploring the inherent soil properties, SOI; capacity of the soil to function, and SFI; the presence of adequately available plant nutrients. The four studied indices were categorized as low, moderate and high classes with percentages of total area for the study area for SFI being: 4.01, 54.46, 31.21%; and for SQI: 19.26, 30.27, 40.15%; while for SDR: 34.00, 29.19, 26.48%; and SRR: 17.80, 56.99 and 14.89%. The SSI was calculated to assess the current state of the soil under the influence of different agricultural management practices. It depends on the area of the square where SQI, SFI, SDR and SRR are the four vertices of the square. The proposed SSI equation obtaining results of: 7.65, 41.88, and 40.15% of total area as low, moderate and high classes, respectively. This work obtained new formula and definition for soil sustainability.