Shear Strength Properties of Organic Soil with Sand Column

This study focused on the effect of particle size of sandy soil on bacterial calcium
carbonate precipitation (BCCP) . Four samples of sandy soil in different particle size
(150-300), (300-600), (600-1mm) and (1mm-2mm), were prepared in glass boxes
having dimension of 6x6x2 cm were treated by immersing in bacterial medium (Bacillus
pasteurii, urea, and CaCl2) for 4 days. The samples were treated by urea medium and
CaCl2 every 6 hours during this treatment period. Throughout the treatment time change in
pH values were monitored each 6 hour. Also, amount of calcium carbonate in all samples
were determined by using calcimeter test at the end of treatment. The test results showed
that the pH values fluctuated between (9-9.3) during treatment stage for all samples. This
range of the pH values indicates that the treatment medium is appropriate for BCCP. It was
also found that the amount of precipitated calcium carbonate in occurred in all samples but
in different percentage, the maximum value of CaCo3 monitored in sandy sample with
particle siaze between (600-1mm) , while the minimum value monitored in sandy sample
with particle size between (1mm-2mm). The results were supported by Scanning electron
microscopy (SEM) analysis and energy-dispersive x-ray (EDX) analysis.

Soil is the largest carbon (C) reservoir in terrestrial ecosystems with twice the amount of atmospheric C and three times the amount in terrestrial vegetation. Carbon related ecosystem services include retention of water and nutrients, promoting soil fertility and productivity and soil resistance to erosion. In addition, changes in the soil C can have strong implications for greenhouse gas emissions from soil with implications in environmental health. The present session highlights the importance of soil C changes, and the interaction among the mechanisms affecting C concentration and stocks in soil. Discussion about the proxies to measure and model C stocks, with special emphasis to cropping systems and natural/semi-natural areas, is encouraged. These proxies should be approached at varying the availability of soil and environment information, including, e.g., soil texture, rainfall, temperature, bulk density, land use and land management, or proximal and remote sensing properties. Studies presented in this session can aim to a wealth of aims, including soil fertility, provision of ecosystem services, and their changes, and the implication for economy, policy, and decision making. Types of contribution appreciated include, but are not limited to, definitive and intermediate results; project outcomes; proposal of methods or sampling and modelling strategies, and the assessment of their effectiveness; projection of previous results at the light of climate change and climatic extremes; literature surveys, reviews, and meta-analysis. These works will be evaluated at the light of the organization of a special issue in an impacted journal Deadlines 15 Jan 2020 for abstract submission EGU2020, 3-8 May, Vienna