Aging effect on the copper sorption on a vineyard soil: column studies and SEM-EDS analysis

Area of Science:

• Environmental Science
• Soil Science
• Geochemistry

Background:

• Copper contamination in soils is a growing environmental concern.
• Understanding soil retention capacity is vital for managing metal bioavailability.

Purpose of the Study:

• To investigate copper uptake and retention in vineyard soil columns.
• To determine the influence of aging time on soil's copper retention capacity.

Main Methods:

• Fixed bed column experiments simulating vineyard soil conditions.
• Investigated copper application through multiple additions versus single application.
• Analyzed copper redistribution using calcium nitrate (Ca(NO3)2) leaching.
• Utilized Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDS) for elemental analysis.

Main Results:

• Multiple copper additions increased soil retention capacity compared to single additions.
• Soil aging significantly enhanced the amount of adsorbed copper.
• Aging reduced available copper during leaching, suggesting a shift from weakly to strongly bound forms.
• SEM-EDS revealed heterogeneous copper distribution, preferentially associated with iron (Fe) and aluminum (Al) fractions.

Conclusions:

• Soil aging is a critical factor enhancing copper retention in vineyard soils.
• The aging process leads to a transformation of copper binding forms, reducing its immediate availability.
• Copper in soil is not uniformly distributed and shows affinity for Fe and Al-rich soil components.