Changes in Microplastic and Associated Elemental Constituents Across Different Rice Farming Systems in North East...

Area of Science:

• Environmental Science
• Soil Science
• Ecotoxicology

Background:

• Global plastic use generates millions of tons of microplastic waste annually.
• Marine microplastic pollution is well-researched, but agroecosystem contamination, particularly in paddy soils, is understudied.
• Microplastics pose environmental and potential health risks.

Purpose of the Study:

• To assess and quantify microplastic pollution in different agricultural land uses in the Cachar district.
• To identify the types, sizes, and elemental composition of microplastics in paddy soils.
• To establish baseline data for managing plastic waste in agroecosystems.

Main Methods:

• Field sampling across four land use types: boro rice, rainfed rice, upland rice, and natural forests.
• Microplastic extraction and quantification (particles per 100 g soil).
• Characterization using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX).

Main Results:

• Boro rice cultivation showed the highest microplastic contamination (213 particles/100 g), while natural forests had the lowest (98 particles/100 g).
• Fibers (89.86%) were the dominant microplastic type, followed by fragments (10.14%).
• Most microplastics were <500 μm (67.79%); SEM/EDX revealed differences in texture and elemental composition (C, O, Al, Si, Cu, S, Br, Mo) between land uses.

Conclusions:

• Agricultural soils, particularly those under intensive rice cultivation, are significant reservoirs of microplastic pollution.
• The findings provide crucial baseline data for developing strategies to mitigate microplastic contamination in agroecosystems.
• Understanding microplastic characteristics is vital for assessing environmental and health impacts.